Common Emitter Amplifier Ppt









44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. 43 Common base hybrid equivalent circuit. Determine two-port model parameters. model mod1 npn. This forward bias is maintained regardless of the polarity of the signal. View Notes - Sedra_Smith_Chapter_08_Modified. There are different types of electronic components in the common emitter amplifier which are R1 resistor is used for the forward bias, the R2 resistor is used for the development of bias, the RL resistor is used at the output it is called as the load resistance. Ahmed ElShafee, ACU : Fall 2017, Electronic Circuits II Effect of the Emitter Bypass Capacitor on Voltage Gain • The emitter bypass capacitor, provides an effective short to the ac signal around the emitter resistor, thus keeping the. The diode on the left side is called an emitter-base diode, and the diodes on the left side are called collector-base diode. • To analyse a circuit: - Each transistor in a circuit is replaced by this model - The "base spreading resistance" R. 3 output resistance of a bjt current source example 10. hie = re hfe = hoe = 1/ro 46 Common-Emitter. There are a few straightforward calculations which can be combined with a simple design flow to give a sure-fire result. They are common-emitter, common-base and common-collector configurations. 23 L15 - 11Mar09 Figure 4. 17 Swamped Amplifier 10. Single transistor amplifiers 5. ECE-312 Electronic Circuits (A) l-a. Transistors are used in amplifiers in three different configurations, namely, Common Base (CB) Common Collector (CC) Common Emitter (CE). namely- emitter, base and collector npn transistor: emitter & collector are n-doped and base is p-doped. h-Parameter Model. Displaying high frequency analysis of bjt PowerPoint Presentations Chapter 13 Output Stages and Power Amplifiers PPT Presentation Summary : Chapter 13 Output Stages and Power Amplifiers 13. CHAPTER 8 Building Blocks of Integrated-Circuit Amplifiers Microelectronic Circuits, Seventh. In turn this increases the current thought the collector circuit, i. Two stage common emitter RC coupled amplifier Circuit Explanation: When input AC. The load resistor in the common collector amplifier being placed in series with the emitter circuit receives both the base current and collector currents. EEE: Free Amplifier Circuits ebooks: Fully Integrated CMOS Power Amplifier Design Using: 9. Two supply voltages VCC and VEE are connected to both the collectors and emitters QI and Q2. Common-Source MOSFET Amplifier Schematic & Analysis. 45 Common-Emitter re vs. We take as an example the Common Emitter Amplifier (CEA) as the configuration to study. 44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. V CC C E B V CC R 1 R E R 2 R s C i v i + v s + _ _ R L C o v o + _ i o i i Common Collector (CC) Amplifier (also called “emitter-follower”) Note: The biasing circuit is the same for each amplifier. In this circuit the base terminal of the transistor serves as the input, the collector is the output, and the emitter is common to both (for example, it may be tied to ground reference or a power supply rail ), hence its name. 3 output resistance of a bjt current source example 10. Using these 3 terminals the transistor can be connected in a circuit with one terminal common to both input and output in a 3 different possible configurations. Input Characteristics Of Common Emitter Configuration Posted on 2020-05-03 2020-05-03 by Transistor configurations. TransistorAmp is an educational program that allows you to design circuit amplifiers with transistors of three different types: common-base circuits, common-emitter circuits, and common-collector circuits. MENU IT FUNDAMENTALS INTRODUCTION TO TRANSISTOR AMPLIFIERS 2 EMITTER INPUT SIGNAL COLLECTOR ourpur SIGNAL BASE BOOKMARK Transistor amplifia. I CBo is defined as the collector current when the emitter is open circuited. Ahmed ElShafee 1 Dr. ) Compared to single stage amplifier, multistage amplifiers provide increased input resistance, reduced output resistance, increased gain, and increased power handling capability. Determine the collector current, ICQ and then find r and ro ANSWERS: ICQ = 5. Decide on an IC that yield to proper gm and r π. ppt, Slides 13-15 NPN Basics: Micro I 01Chapter 6-1. Common source amplifier Common gate amplifier λ1 ≠0 EE105Spring2008 Lecture20,Slide10 Prof. The object is to solve for the small-signal voltage gain, input resistance, and output resistance. The typical values for hFE range from 75 to 200, depending on the type of BJT. Common emitter hybrid equivalent circuit. BJT AMPLIFIERS Questions :-1. 1 The High-Frequency Gain Function. 1v throughout the active range of the transistor which may change base current by a factor of 10 or more. Calculator. 4 More about BJT Amplifier. Multistage amplifiers are amplifier circuits cascaded to increased gain. The DC bias voltage applied to the emitter base junction, makes it remain in forward biased condition. Analyze the small-signal equivalent circuit Equivalent Circuit for Common Emitter. Emx1 / umx1n / imx1 datasheet labsolute maximum ratings (ta = 25°c) parameter symbol values unit collector-base voltage vcbo 60 v collector-emitter voltage vceo 50 v emitter-base voltage vebo 7 v collector current ic 150 ma power dissipation. The transistor is connected as a current amplifier: • Driven by a current source • Driving a current meter f. 공부하시는데에도 어느정도 도움이 되리라 생각됩니다. The Questions and Answers of An npn transistor operates as a common emitter amplifier , with a power gain of 60dB. Between the two stage emitter follower is inserted for impedance matching. Here the individual stages of the amplifier are connected together using a resistor-capacitor combination due to which it bears its name as RC Coupled. In a common emitter mode (i. Since collector to be 'common', it is tied into a power supply and now it's available to the entire circuit. 5 2000 0 0) r1 1 2 1k q1 3 2 0 mod1 rspkr 3 4 8 v1 4 0 dc 15. The reason for this can be seen from the fact that as the input voltage rises, so the current increases through the base circuit. The objective of this lab is to design and build a direct coupled two-stage amplifier, including a common-source gain stage and a common-collector buffer stage. In the Cutoff State both Emitter Base Junction and Collector Base junctions are reverse biased. Here the Base-Emitter junction is forward bias because of the voltage drop across the RB or you can say the base is more positive with respect to the emitter, which is the result of IB. We also learned how different biased circuits compare and the different uses and formats for a common emitter amplifier. A major fault of a single-stage common emitter amplifier is its high output. 1 General Considerations 13. It compares linear and nonlinear (switching) amplifiers and explains how to use transistor curves to analyze amplifier operation in terms of operating regions, load lines, operating (Q) points, and biasing. An Alternative Biasing Arrangement Biasing Using a Current Source The BJT can be biased using a current source The advantage is that the emitter current is independent of the values b and RB Current-source biasing leads to significant design simplification Common-Emitter Amplifier Common-Emitter Amplifier (cont. Common Emitter BJT Amplifier Design Current Mirror Design [16721] Some Random Observations Conditions for stabilized voltage source biasing Emitter resistance, RE, is needed. 6% distortion. If this load line is drawn only when DC biasing is given to the transistor, but no input signal is applied, then such a load line is called as DC load line. We will be discussing this configuration, as well as the common-base and common-collector, in a little while. 7 Small-Signal Equivalent Circuits. This is mainly because the input impedance is LOW as it is connected to a forward-biased PN-junction, while the output impedance is HIGH as it is taken from a reverse-biased PN-junction. 2 B-E junction characteristics 0 Quiescent base current and B-E voltage IÅ)ad line ic (mA) 6 5 lc (sat) — 4 3 2 1 0 Forward-active mode Saturation Load line Q-point (on) = 07 V VBB- o 2 4 6 8 30 25 20 15 ILA 10. Common Base Amplifier. ws The common emitter amplifier configuration produces the highest current and power gain of all the three bipolar transistor configurations. Perform a dc analysis and hence calculate the voltage gain Av where; vo Av = vs. An amplifier that conducts for half the input cycle. Tag : transistor as an amplifier working pdf. EEE: Free Amplifier Circuits ebooks: Common Cathode Amplifier Design Ideas: 8. The common-collector amplifier is also known as an emitter-follower. Transistor as an Amplifier in Common Emitter. 3 The coupling capacitor (C S and C C) is used to pass the ac input signal and block the dc voltage from the preceding circuit. Conclusion In this experiment, we learned what a common emitter amplifier is and how it works. 34b Common-emitter amplifier. Clif Fonstad, 11/12/09 Lecture 18 - Slide 11. ppt [Compatibility Mode] Author: Ning Beiijia. Two cascaded common emitter stages are shown. Signal clipped at collector due to lack of DC base bias. • This topology will decrease the gain of the amplifier but improve other aspects, such as linearity, and input impedance. Relates collector current IC to base-emitter voltage VBE: IS=Saturation Current Similar to Diode Law Recall IB=IC/β VBE IC Collector current is controlled by the base-emitter voltage VBE BJT Amplifier To act as an amplifier, first bias the transistor to get it into active mode Then superimpose a small signal vbe on the base Under DC conditions. 16 2 • The signal is generally the o/p of a transducer like microphone, thermo couple. Bias amplifier in high-gain region Note that the source resistor R S and the load resistor R L are removed for determining the bias point; the small-signal source is ignored, as well. 4 Useful Tools for the Analysis of the High-Frequency Response of Amplifiers. • BJT Common emitter and FET common source biasing. This amplifier can actually be viewed as either an inverting common emitter amplifier when driven from V neg and with V pos considered an AC ground. The diode on the left side is called an emitter-base diode, and the diodes on the left side are called collector-base diode. 2 B-E junction characteristics 0 Quiescent base current and B-E voltage IÅ)ad line ic (mA) 6 5 lc (sat) — 4 3 2 1 0 Forward-active mode Saturation Load line Q-point (on) = 07 V VBB- o 2 4 6 8 30 25 20 15 ILA 10. The common- collector has a high current gain and voltage gain of 1. Asutosh Kar, IIIT Bhubaneswar. I have tried A LOT of websites, including youtube, wiki, howstuffworks, and even the teacher. In our previous article, we have explained the amplifiers theory, power amplifier circuit, diodes, rectifiers in detail. Most transistors amplifiers are designed to operate in the linear region. Conclusion In this experiment, we learned what a common emitter amplifier is and how it works. A single stage transistor amplifier has one transistor, bias circuit and other auxiliary components. acts as an emitter follower, thus giving the second stage a high input resistance. Types of Amplifiers. The typical values for hFE range from 75 to 200, depending on the type of BJT. • This topology will decrease the gain of the amplifier but improve other aspects, such as linearity, and input impedance. Ahmed ElShafee, ACU : Fall 2018, Electronic Circuits II Effect of the Emitter Bypass Capacitor on Voltage Gain • The emitter bypass capacitor, provides an effective short to the ac signal around the emitter resistor, thus keeping the. The emitter terminal is connected to the left side n-type layer. The phase shift of 180 degrees between input and output signals is the same as that of common- cathode vacuum tube circuits (and common-emitter transistor circuits). h-parameter Model for Common Emitter. com, find free presentations research about Bjt PPT. Large Signal Amplifiers Large Signal Amplifiers are also known as Power Amplifiers. Phototransistor Definition: The phototransistor is a three-layer semiconductor device which has a light-sensitive base region. Rayas Sánchez 4 Common Emitter (CE) π. 공부하시는데에도 어느정도 도움이 되리라 생각됩니다. MULTISTAGES AMPLIFIER. 소개글 common emitter amplifier의 소신호에 관한 pre report로서 이론이 정말 상세히 정리되어있습니다. 23: Common Emitter Amplifier Frequency Response. 25: Enhancement Type MOSFET Operation, P-Channel, and CMOS. In electronics, a common-emitter amplifier is one of three basic single-stage bipolar-junction-transistor (BJT) amplifier topologies, typically used as the voltage amplifier. As such, the circuit con gura-tion as is shown has as a poor bias. The figure below shows a Common base amplifier. Cutoff Q-point Amplification Common-emitter (CE) Class B amplifier The dc operating (bias) point of an amplifier. Types of Amplifiers. This equivalence applies only for differential input signals. amplifier Figure 7. hybrid-π model of a BJT in the common-emitter configuration is presented in Figure 4. The object is to solve for the small-signal voltage gain, input resistance, and output resistance. 2c is called common-collector configuration which is typically used as a voltage. In electronics, a common-emitter amplifier is one of three basic single-stage bipolar-junction-transistor (BJT) amplifier topologies, typically used as the voltage amplifier. 13 Operational Amplifiers. The common emitter amplifier construction delivers the very best current and power gain among the 3 bipolar transistor designs. In other words, the common base amplifier attenuates the electric current rather than amplifying it. Liu, UC Berkeley. This circuit has grounded emitter. However the voltage gain may be more, but it is a function of input and output resistances (and also the internal resistance of the emitter-base junction). common-emitter. Emitter Degeneration • By inserting a resistor in series with the emitter, we "degenerate" the CE stage. 45 Common-Emitter re vs. DESIGN PRINCIPLES. model mod1 npn. R 1 and R 2. BJT Amplifier (continued) An 8 mV peak change in vBE gives a 5 µA change in iB and a 0. It means that there is a phase difference of 180 o between the input and output. This single output transistor is biased around the Q-point within the middle of its load line and so is never driven into its cut-off or saturation regions thus allowing it. 5 mA change in iC. Patil,IITBombay 1 Common-Emitter Amplifier The circuit diagram of a common-emitter (CE) amplifier is shown in Fig. oStable and robust bias point should be resilient to variations in µ n C ox (W/L),V t (or β for BJT) due to temperature and/or manufacturing variability. Common base. This article presents how to achieve a proper biasing of bipolar transistors. In this circuit the base terminal of the transistor serves as the input, the collector is the output, and the emitter is common to both (for example, it may be tied to ground reference or a power supply rail ), hence its name. CE with Emitter Resistance (Emitter Degeneration) Effect of R e (called "Emitter Degeneration"): (1) increase input resistance by (1+g m R e) (2) reduce voltage gain by (1+g m R e) (3) reduce v be by (1+g m R e) → lower nonlinear distortion (4) voltage gain less dependent on β (5) improved high frequency response 12-12 Common-Gate (CG) Amplifier. • Common dB values. 9Voltage Gain 10. 16 The pnp BJT. h-parameter Model for Common Emitter. Since v out follows exactly the v in therefore, there is no phase inversion. | PowerPoint PPT presentation. Lecture23-Amplifier Frequency Response 5 Common-Emitter Amplifier - ωH High Frequency Response - Miller Effect (cont. The single stage common emitter amplifier circuit shown above uses what is commonly called "Voltage Divider Biasing". o Amplifier response at high frequencies (near the upper cut-off frequency , f H. How to establish a Bias point (bias is the state of the system when there is no signal). h-Parameter Model. Comparison of Amplifier Configurations Midband Characteristics* These are approximate expressions neglecting the effects of the biasing resistors R1 and R2 and the source resistance RS. (i) For the common-base configuration: the lower case letter b (ii) For the common-emitter configuration: the lower case letter e (iii) For the common-collector configuration: the lower case letter c Complete hybrid equivalent model TRANSISTOR AS AMPLIFIER An n–p–n transistor in the common-base bias mode EXPRESSIONS OF CURRENT GAIN, INPUT. It has a high input impedance and low output impedance. 012 Spring 2007 Lecture 19 1 Lecture 19 Transistor Amplifiers (I) Common-Source Amplifier Outline • Amplifier fundamentals • Common-source amplifier • Common-source amplifier with current-source supply Reading Assignment: Howe and Sodini; Chapter 8, Sections 8. Normally, voltage gain A v and current gain A i are high. We need to include RE for good biasing (DC. PowerPoint slide on Bipolar Junction Transistors compiled by D. Find PowerPoint Presentations and Slides using the power of XPowerPoint. 9 • For the common-collector configuration, the model defined for the common-emitter configuration of is normally applied rather than defining a model for the common-collector configuration. Differential and Multistage IC Amplifiers TLT-8016 Basic Analog Circuits 2005/2006 2 7. Skip navigation. The coupling capacitor C1. 5m/20 µ = 125 BJT DC Analysis - Summary Calculating the Q-point for BJT is the first step in analyzing the circuit To summarize: We ignored the AC (variable) source Short circuit the voltage sources Open Circuit the current. Quiescent point of V out will be determined by R C. "1 - K " acting on equals the common emitter amplifier mid-band gain, i. View Transistor Amplifiers. 5 k CALCULATION OF GAIN Voltage Gain, AV = vo / vs Current Gain, Ai = iout / is Small-Signal Voltage Gain: Av = Vo / Vs ib Common-Emitter Amplifier Remember that for Common Emitter Amplifier, the output is measured at the collector terminal. 5 AC response BJT amplifier. The collector-base diode and the base-emitter diode appear to be in series, connected back-to-back. ws The common emitter amplifier configuration produces the highest current and power gain of all the three bipolar transistor configurations. , common source, emitter follower) that we have studied. Ri = rbe + 2REE ( hfe +1), where rbe is the base to emitter small signal resistance, hfe is the small signal common emitter current gain of the transistor and REE is the common emitter resistance. Collector becomes common to both input and output and the amplifier is Common Collector (CC) amplifier or Emitter Follower (EF) amplifier. Exam 2 information Open book, open notes, bring a calculator Eligible topics (2 of 3) (not an exhaustive list) BJT Amplifiers BJT as amplifier Active-mode operation small-signal condition for linear operation Small-signal models transconductance (gm), current gain ( ) hybrid-pi model: input resistance (rp), output resistance (ro) T model: input. 2 \$\begingroup\$. Common emitter current gain beta (β) = Ic/Ib as in common emitter configuration input current is Ib and output current is Ic. oStable and robust bias point should be resilient to variations in µ n C ox (W/L),V t (or β for BJT) due to temperature and/or manufacturing variability. Cascading amplifiers is done for many reasons. This arrangement where the emitter (E) is in the controlling circuit (base current) and in the controlled circuit (collector current) is called common emitter mode. Bipolar Junction Transistor Bipolar Junction Transistors Characteristics: The three parts of a BJT are collector, emitter and base. Amplifiers are used to increase the amplitude of a voltage or current, or to increase the amount of power available usually from an AC signal. Here you'll use a low voltage transistor with desirable beta vs Ic as common emitter and a high voltage transistor as common base. 3 V This is a silicon transistor because 2. The Common Collector and the Common Base con-figurations are sometimes used in the input or output stages of an amplifier when impedance matching is required. Thus: o A practical amplifier acts as an ideal linear amplifier only for a range of frequencies, called the "mid-band". The type of amplifier shown is a a. •The CB-Common Base Amplifier has the input signal applied to the emitter and the output signal coming from the collector. 43 Common base hybrid equivalent circuit. 3 Push-Pull Stage 13. value of the transistor itself. 1 General Considerations 13. 1 3 2 (Source/emitter follower) Source/emitter degeneration. Author: Student Created Date: 01/18/2017 01:57:03 Title: PowerPoint Presentation Last modified by: Student. Differential and Multistage IC Amplifiers TLT-8016 Basic Analog Circuits 2005/2006 2 7. In other words, the common base amplifier attenuates the electric current rather than amplifying it. Grabel, Microelectronics, 2nd Ed. PowerPoint slide on OP-Amps compiled by Pranav Poddar. This section thus provides the required voltage gain for the multi-stage amplifier. Inductively Coupled Amplifier An example of an inductively coupled amplifier is presented to the right and is based on Figure 8. 16 2 • The signal is generally the o/p of a transducer like microphone, thermo couple. pdf; Diodes and Half Wave Rectification. Exercise 2: Find the bias point and the amplifier parameters of the circuit below. Lecture23-Amplifier Frequency Response 5 Common-Emitter Amplifier - ωH High Frequency Response - Miller Effect (cont. This section thus provides the required voltage gain for the multi-stage amplifier. Audio amplifier output power may be anything from less than 1 Watt to several hundred Watts. Setelah diketahui bahwa pada Common Emitter nilai Zi = re ; arus collector Ib output impedance adalah ro , maka bentuk ekuivalen model yang cocok untuk common emitter adalah : CONTOH : Jika diketahui sebuah penguat Common Emitter dg nilai = 120 IE = 3. Common Emitter (CE) Amplifier Bias: Choose R 1 & R 2 to set V B V E is then set. Multistage Transistor Amplifiers 289 „ ∴ Increase in db power gain = 10 log 10 1000 – 10 log 10 100 = 30 – 20 = 10 db. The common emitter current gain βis :a)104b)60c)102d)6 x102Correct answer is option 'C'. The common emitter configuration has a current gain approximately equal to the. | PowerPoint PPT presentation. 1 shows the circuit diagram of a single stage common-emitter amplifier. Comparison of Amplifier Configurations Midband Characteristics* These are approximate expressions neglecting the effects of the biasing resistors R1 and R2 and the source resistance RS. The BJT transistors have mainly three types of configurations. 1 Lab 02: Part B Amplifier Frequency Response (20 points) NOTE: 1) Please refer to Part A if you have not already built an NPN-based common emitter amplifier or NMOS-based common source amplifier. ppt, Slides 8-11. 1 General Considerations 13. Bypass capacitors are used to force signal currents around elements by providing a low impedance path at the frequency. A good di erential ampli er should reject Vic entirely, i. Base-Emitter is forward biased due to R B R B sets the quiescent (steady-state with no input signal applied) base I BQ, I CQ, V OQ, V CEQ V BE=0. ¾Generally, you must have I DS>0 and V DS>0 (for N-MOSFETs). 43 Common base hybrid equivalent circuit. Common emitter configuration as current amplifier. The base is made common to both input and the output circuits. VR1 = VCC – VB = 12 – 4 = 8 V Transconductance=how much IC changes with a fluctuation in VBE. Electronics-tutorials. In this transistor emitter and collector is P-type. Bipolar Transistor Based –Small Signal (Common Mode) Both arms of differential amplifier are symmetrical. The three types of configurations are Common Base, Common Emitter and Common Collector configurations. Impossible with a single stage –> multi-stage amps. EEE: Free Amplifier Circuits ebooks: NOTES The Common Emitter: 10. Cutoff Q-point Amplification Common-emitter (CE) Class B amplifier The dc operating (bias) point of an amplifier. CMOS multi-stage voltage amplifier ⇒Multistage amplifier VBIAS. We take as an example the Common Emitter Amplifier (CEA) as the configuration to study. •The first step is to indicate the direction of IE as established by the arrow in the transistor symbol. The circuits are already created; you don't need to know about placing or connecting the components, the formulas, or how to create a circuit. C C C 1−K C K=−g m R C. RELATED TOPICS ON SMALL SIGNAL AMPLIFIERS broad band amplifiers buffer amplifiers emitter degeneration negative feedback. The modes are. The current gain is just less than 1, and the output impedance is simply Rc 8. Common emitter hybrid equivalent circuit. This forward bias is maintained regardless of the polarity of the signal. com - id: 4c0fad-OGVmZ. 1) Figure 4. Common base. BJT AMPLIFIERS Questions :-1. This article presents how to achieve a proper biasing of bipolar transistors. | PowerPoint PPT presentation. A BJT is made up of a silicon crystal or germanium crystal in which a thin layer of n-type. Chapter 9 Common-Emitter Amplifiers Amplifier Gain The common-emitter (CE) amplifier provides voltage, current, and power gain. In a common emitter mode (i. Fig 1: Understanding the load-line concept begins with a standard common-emitter configuration of a PNP transistor amplifier. The base terminal is connected to the p-type layer. Design Procedure. 44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. 2 The effect of non-zero hoe on common-emitter amplifiers with an emitter resistor 5. It compares linear and nonlinear (switching) amplifiers and explains how to use transistor curves to analyze amplifier operation in terms of operating regions, load lines, operating (Q) points, and biasing. Transistor in active region. 9 V and ICQ = 2. Basic FET common source amplifier. The following will be discussed in this chapter: Review frequency domain analysis, BJT and MOSFET models for frequency response, Frequency Response of Intrinsic Common-Emitter Amplifier, Effect of transistor parameters on fT. 6% distortion. The common emitter transistor amplifier is the only configuration that gives an inversion, 180°, between the input and output signals. A cascode is one form of amplifier that is designed so that the first stage is exposed to only varying currents not voltages. Common emitter BJT circuit for determining output characteristics Figure 7 shows the qualitative characteristic curves of a BJT. Niknejad Small-Signal Two-Port Models We assume that input port is linear and that the amplifier is unilateral: - Output depends on input but input is independent of output. Because CE amplifier have greater efficiency in increasing voltage and current of AC signal. 6 volts below the base. Whatever the task, there are three categories of amplifier that relate to the properties of their output; 1. Where the value of re is:. Inserting the device equations into the B-E KVL: 57 10 07 299 1 0. 52 Common Emitter Mixer 2. This circuit stabilizes collector current instead of base current, thus reducing the effects of beta variations and temperature on the quiescent operating. The first step is to indicate the direction Microsoft PowerPoint - 3_Bipolar Junction Transistors. Common gate/base. AC Voltage Gain: The AC voltage gain of CC amplifier is calculated as E V Ee R A Rr (1. 1 Design Rules for Discrete and Integrated Circuits Discrete circuits: the elements are manufactured separately and are mounted on a printed. 2k c) Av if RL=1. Common emitter current gain beta (β) = Ic/Ib as in common emitter configuration input current is Ib and output current is Ic. 23 L15 - 11Mar09 Figure 4. Common emitter hybrid equivalent circuit. txt) or view presentation slides online. Since the emitter of a transistor is the sum of the base and collector currents, since the base and collector currents always add together to form the emitter current, it would be reasonable. (Si BJT with β = 200, V A = 150 V, ignore Early effect in bias calculations). 3V If v in is 3V, v out = 2. 43 Common base hybrid equivalent circuit. Among all these three configurations common-emitter configuration is mostly used type. Cascading amplifiers is done for many reasons. the ac load line will tell you the maximum possible peak-to-peak output voltage V ce(cut off) from a given amplifier. Identify the amplifier’s configuration (CE, CB, etc. 2 (i) shows the basic circuit of a differential amplifier. Another reason for using bjt cascodes is that a low voltage transistor can be protected from high collector voltages in high voltage amplifiers. Download Transistor as an Amplifier PowerPoint Presentation. EEE: Free Amplifier Circuits ebooks: The Pros and Cons of. The DC bias voltage applied to the emitter base junction, makes it remain in forward biased condition. Bipolar Transistor Based -Small Signal (Common Mode) Both arms of differential amplifier are symmetrical. Ahmed ElShafee 1 Dr. The classification of the amplifier is based on the device terminal which is common to both input and output circuit. The transistor is the primary building block of all microchips, including your CPU, and is what creates the binary 0's and 1's (bits) your computer uses to communicate and deal with Boolean logic. The common emitter amplifier configuration produces the highest current and power gain of all the three bipolar transistor configurations. The BJT transistors have mainly three types of configurations. EE105 Fall 2007 Lecture 8, Slide 2Prof. 16-136 in an app-note by Roy Hejhall "RF SMALL SIGNAL DESIGN USING TWO-PORT PARAMETERS", Appendix I. Junction capacitances, high-frequency hybrid π model. It is quite easy to adopt preferred component values in the common emitter amplifier design. • No change in the frequency of the input signal What is an amplifier? 2. Transistors Review : What is a Transistor ? Some Transistor Applications I Current Source Some Transistor Applications II The Emitter Follower I The Emitter Follower II Emitter Follower (a bit diff. Transistor is operated in three configurations called as common base, common emitter and common collector. Output taken from. A good di erential ampli er should reject Vic entirely, i. Or, Z o = r o , as shown in the figure. The capacitor CB is used to couple the input signal to the input port of the amplifier, and CC is used to couple the amplifier output to the load resistor RL. C Cp Cn T Ep Cn T E Cn Cp T Ep T E. Common Emitter Amplifier Circuit: Consider the Common Emitter Amplifier Circuit circuit shown in Fig. Observe that the offset and D. Electronics-tutorials. Ideally, the output impedance Z o. Class D Audio Amplifier Design (PDF 54p) 7. As a result it can achieve gain bandwidths orders of magnitude larger than the common emitter amplifiers. Equivalence of the differential amplifier (a) to the two common-emitter amplifiers in (b). 5m/20 µ = 125 BJT DC Analysis - Summary Calculating the Q-point for BJT is the first step in analyzing the circuit To summarize: We ignored the AC (variable) source Short circuit the voltage sources Open Circuit the current. The schematic diagram for an inverting amplifier is shown in Figure (a). 13 Voltage Gain of Unloaded CE Amplifier 10. Title: Microsoft PowerPoint - Hand-Lec31-BJT7. Common emitter hybrid equivalent circuit. By reading the above information you have got an idea about this concept. Common source/emitter. common emitter or common collector. NPN transistor contains three semiconductors and two PN junctions between them. Amplifier fundamentals 2. The Common Emitter Amplifier. 3 ECE 3120 Microelectronics II Dr. Common gate/base. ) Compared to single stage amplifier, multistage amplifiers provide increased input resistance, reduced output resistance, increased gain, and increased power handling capability. Common Emitter BJT Amplifier Design Current Mirror Design [16721] Some Random Observations Conditions for stabilized voltage source biasing Emitter resistance, RE, is needed. This phenomenon is called the "Miller effect" and the capacitive multiplier "1 - K " acting on equals the CE amplifier mid-band gain, i. The basic concept of class C operation is illustrated below. 6–3 The Common-Emitter Amplifier 6–4 The Common-Collector Amplifier 6–5 The Common-Base Amplifier 6–6 Multistage Amplifiers 6–7 The Differential Amplifier 6–8 Troubleshooting Device Application CHAPTER OBJECTIVES Describe amplifier operation Discuss transistor models Describe and analyze the operation of common-emitter amplifiers. The base or gate terminal of the transistor serves as the input, the collector or drain is the output, and the emitter or source is common to both input and. VR1 = VCC – VB = 12 – 4 = 8 V Transconductance=how much IC changes with a fluctuation in VBE. Common-Emitter (CE) Fixed-Bias Configuration The input (Vi) is applied to the base and the output (Vo) is from the collector. The circuits are already created; you don't need to know about placing or connecting the components, the formulas, or how to create a circuit. Two stage common emitter RC coupled amplifier Circuit Explanation: When input AC. ppt, Slides 8-11. 3 Load-Line Analysis of a Common-Emitter Amplifier. The schematic diagram for an inverting amplifier is shown in Figure (a). Fixed bias Common-Emitter Configuration (a) (b) Figure 3 Fixed bias Common-Emitter Configuration Note in Fig. Basic FET common source amplifier. Get Here- Download Transistor as an Amplifier PowerPoint Presentation. As vin(t) goes positive, the load line moves upward and to the right, and the value of iB increases. Junction capacitances, high-frequency hybrid π model. This equivalence applies only for differential input signals. 9825vs Rte= RskRE=98. You can choose the best of your choice and interest from the list of topics we suggested. 43 Common base hybrid equivalent circuit. The reason for this can be seen from the fact that as the input voltage rises, so the current increases through the base circuit. • Common-collecter (emitter-follower) configuration. 45 Common-Emitter re vs. Redraw the network in more convenient and logical form Common-Emitter (CE) Fixed-Bias Configuration The input (Vi) is applied to the base and the output (Vo) is from the collector. Displaying high frequency analysis of bjt PowerPoint Presentations Chapter 13 Output Stages and Power Amplifiers PPT Presentation Summary : Chapter 13 Output Stages and Power Amplifiers 13. This circuit stabilizes collector current instead of base current, thus reducing the effects of beta variations and temperature on the quiescent operating. Total base-emitter voltage is: be v BE V BE v += Collector-emitter voltage is: This produces a load line. • Also, the equation IE = IC + IB still holds. common vet tech, investigatory project on comparative study of common antacids, common sources of industrial accident ppt, to set up a common base transistor circuit, how to take seminar about applications of common base configuration, transpired solar collector, evacuated tube solar collector seminar pdf, Common Base Amplifiers. TECH 150 LAB #12 THE EMITTER FOLLOWER AMPLIFIER Name Introduction The common emitter amplifier that you examined previously had a high voltage gain, but the input resistance was low which may load Fill & Sign Online, Print, Email, Fax, or Download. Ernest Kim Last modified by: ekim Created Date: 3/5/2001 6:18:02 PM Document presentation format. 3 (a) that the common ground of the dc supply and the transistor emitter terminal permits the relocation of R B and R C in parallel with the input and output sections of the transistor, respectively. A single stage transistor amplifier has one transistor, bias circuit and other auxiliary components. ppt [Compatibility Mode] Author: mghoneima. As you can see it's two transistors which share a common collector and the emitter of the first feeds the base of the second without any intermediating resistor. 2(ii) shows the symbol of differential amplifier. com, find free presentations research about Common Emitter PPT. Key to Voltage regulation • The transistor tries to regulate itself so that the voltage drop between the Base and the Emitter is always about 0. RL + out - LO+. Medium input impedance 2. The common emitter amplifier is a three basic single-stage bipolar junction transistor and is used as a voltage amplifier. Bel is a form of gain measurement and is commonly used to express amplifier response. The Common Emitter circuit is most widely used configuration. In the Cutoff State both Emitter Base Junction and Collector Base junctions are reverse biased. Animation shows a single stage CE amplifier and its working. Pada umumnya, transistor memiliki 3 terminal. The load line is drawn by joining the saturation and cut off points. 23: Common Emitter Amplifier Frequency Response. Section I3: Feedback Amplifiers We are now going to discuss two specific examples of voltage and current feedback using the common-emitter (emitter-resistor) amplifier configuration. 2 mA dan ro = Takterhingga , tentukan : (a)Zi (b)Av jika diberi beban 2k (c)Ai dengan beban 2k. The arrangement is the same for a PNP transistor, but bias will be opposite w. 22 3-7 (a) base-emitter junction characteristics and the input load line and (b) common- emitter transistor characteristics and the collector-emitter load line -2! = 18. 소개글 common emitter amplifier의 소신호에 관한 pre report로서 이론이 정말 상세히 정리되어있습니다. 2 PPT Presentation Summary : Chapter 13 Output Stages and Power Amplifiers 13. The transistor is the primary building block of all microchips, including your CPU, and is what creates the binary 0's and 1's (bits) your computer uses to communicate and deal with Boolean logic. input to the amplifier is at Base 2. Decide on an IC that yield to proper gm and r π. The downside to reverse active mode is the β (β R in this case) is much smaller. Perform a dc analysis and hence calculate the voltage gain Av where; vo Av = vs. ac equivalent of fixed-bias CE amplifier using h-parameter model; 17 Common-Emitter Amplifier. This phenomenon is called the “Miller effect” and the capacitive multiplier “1 – K ” acting on equals the common emitter amplifier mid-band gain, i. Re : Calcul de résistance - BFR520 Common Emitter Amplifier Envoyé par DAUDET78 PS : mettre des condensateurs de 10µF de couplage, c'est une grosse erreur à 550Mhz. 44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. TRANSISTOR AMPLIFIERS Common Emitter Amplifier Signal path: When a signal is applied to an amplifier, four things occur. Tag : transistor as an amplifier ppt. In common emitter transistor configuration, the input signal is applied between the base and emitter terminals of the transistor and output appears between the collector and base terminals. The base or gate terminal of the transistor serves as the input, the collector or drain is the output, and the emitter or source is common to both input and. The CEA is one of the three elementary configurations of bipolar transistors to realize a signal amplifier. Designing Audio Power Amplifiers. The capacitor CB is used to couple the input signal to the input port of the amplifier, and CC is used to couple the amplifier output to the load resistor RL. Design Rules. A common-emitter class C amplifier with a resistive load is shown in the following circuit topology. 44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. Class A Amplifiers are the most common type of amplifier topology as they use just one output switching transistor (Bipolar, FET, IGBT, etc) within their amplifier design. 4 Bandwidth. Name of the file gives good info. Components Qty Device 1 2N2222 BJT Transistor 1 2N7000 MOSFET Transistor 3. Signal clipped at collector due to lack of DC base bias. 4 More about BJT Amplifier. The video is NOT intended to take. The resistors R1 and R2 form a voltage divider to provide a stable base voltage. In the next tutorial about amplifiers, we will look at the most commonly connected type of transistor amplifier circuit, the common emitter amplifier. üdifferential amplifiers 10. common-emitter. The common- emitter amplifier has high voltage and current gain. NPN transistor structure you can see below. Presentation of the Common Emitter Amplifier. The Common Emitter Amplifier. This is mainly because the input impedance is LOW as it is connected to a forward biased PN-junction, while the output impedance is HIGH as it is taken from a reverse biased PN-junction. These names are given as per the name of the terminals. Voltage and Current Sources Circuit Symbols “IDEAL” or “Independent” Sources IDEAL voltage source maintains the prescribed voltage across its terminals regardless of the current drawn from it IDEAL current source maintains the prescribed current through its terminals regardless of the voltage across those terminals “Controlled” or “Dependent” Sources A voltage or current source. 6EF amplifier and Design 1. 1 The High-Frequency Gain Function. Suppose a BJT with a 5V supply is designed to switch a 5V, 20mA lamp on and off. Find PowerPoint Presentations and Slides using the power of XPowerPoint. Select an RC to place the transistor. Calculate the DC operating point (bias circuit) 2. This equivalence applies only for differential input signals. Clif Fonstad, 11/12/09 Lecture 18 - Slide 11. RESOURCES HELP INTERNET. , biased) push-pull amplifiers. The characteristic curve drawn against variations of base current and base-emitter voltage is input characteristic of a common emitter transistor. 6 Announcements:. I have tried A LOT of websites, including youtube, wiki, howstuffworks, and even the teacher. 2 Emitter Follower as Power Amplifier 13. Millman and A. h-Parameter Model. php on line 143 Deprecated: Function create_function() is deprecated in. 1 General Considerations 13. I I I I I I I I I I = + = + = + = = α γα α γα. model mod1 npn. In the first part, we learned about different biasing setups with it being either fixed or self. In the case of a bjt amplifier this can help reduce unwanted effects of ca. Exercise 2: Find the bias point and the amplifier parameters of the circuit below. Common-Emitter Amplifiers Supplementary Lecture S2 to Aero 2 Signals & Systems (Part 2) Professor Peter Cheung Department of EEE, Imperial College London (Slides from Dr Andy Holmes) Aero 2 Signals & Systems (Part 2) S2. The coupling capacitor C1. The middle section of the NPN. connected to a common emitter RE so that the two input signals are affected by either or both input signals. In this circuit the base terminal of the transistor serves as the input, the collector is the output, and the emitter is common to both (for example, it may be tied to ground reference or a power supply rail), hence its. 35 Common-emitter amplifier of Example 4. A transistor acts as an amplifier by raising the strength of a weak signal. Ideal amplifier has high gain, high r in, low r out. Obtain the small-signal equivalent circuit at medium frequencies 3. This is the origin of the nomenclature of the three types of transistor amplifiers: common collector, common emitter, and common base. Base voltage source will have finite resistance, RB. Download Transistor as an Amplifier PowerPoint Presentation. 1 The High-Frequency Gain Function. Experience in design of a single stage amplifier. The common emitter/source amplifier is one of three basic single-stage amplifier topologies. The Darlington emitter follower has a higher minimum input and output resistance than the augmented system and exhibits a greater constancy. h-Parameter Model. Other than the Traditional amplifiers, there are few more classes, which are class E, Class F, Class G, and H. 2c is called common-collector configuration which is typically used as a voltage. The arrow in the symbol defines the direction of emitter current through the device. The common base amplifier circuit using npn transistor. common vet tech, investigatory project on comparative study of common antacids, common sources of industrial accident ppt, to set up a common base transistor circuit, how to take seminar about applications of common base configuration, transpired solar collector, evacuated tube solar collector seminar pdf, Common Base Amplifiers. The main part of the working of this transistor is the middle part or base part which is p-type. Look at the connection between the Base and Emitter first. Introduction to BJT Amplifier Small signal or AC equivalent circuit parameters Have to calculate the DC collector current by performing DC analysis first Common Emitter-Emitter Grounded Voltage gain Current gain Common-Collector (Emitter-Follower) Amplifier Remember that for Common Collector Amplifier, the output is measured at the emitter. Output is taken across R L, connected to the collector of the transistor. txt) or read online for free. 704-720 In addition to common-emitter, common-collector (i. Animation shows a single stage CE amplifier and its working. TA: Mahfuz (24 Sep. Common-source amplifier 3. First replace VCC with ac ground and all capacitors short. Choose R1 and R2 to provide necessary value of VX and establish I1>>IB. Transistors Review : What is a Transistor ? Some Transistor Applications I Current Source Some Transistor Applications II The Emitter Follower I The Emitter Follower II Emitter Follower (a bit diff. Both of these inductors are coupled to L3, and the circuit oscillates at a frequency determined by L3-C1. Video Amplifiers. 4 Improved Push-Pull. It has a high input impedance and low output impedance. 25: Enhancement Type MOSFET Operation, P-Channel, and CMOS. There are different types of electronic components in the common emitter amplifier which are R1 resistor is used for the forward bias, the R2 resistor is used for the development of bias, the RL resistor is used at the output it is called as the load resistance. connected to a common emitter RE so that the two input signals are affected by either or both input signals. Common emitter BJT Amplifier 1 C 2 X πfC The higher the freq. How are amplifiers classified according to the transistor configuration? 1. Common emitter BJT circuit for determining output characteristics Figure 7 shows the qualitative characteristic curves of a BJT. Common emitter configuration as current amplifier. 44 Simplified General h-Parameter Model The model can be simplified based on these approximations: hr 0 therefore hrVo = 0 and ho (high resistance on the output) Simplified. Common Emitter Amplifier. ¾MOSFETs are used in most. h-Parameter Model. Total base-emitter voltage is: be v BE V BE v += Collector-emitter voltage is: This produces a load line. (ii) shows the output characteristcs along with the d. T is the frequency at which the current gain drops to unity. The common emitter amplifier is one of the most common transistor amplifier. Wu, UC Berkeley • In common base topology, where the base terminal is biased with a fixed voltage, emitter is fed with a signal, and collector is the output. This circuit stabilizes collector current instead of base current, thus reducing the effects of beta variations and temperature on the quiescent operating. However, another two amplifier configurations can also be used to provide some power gain, or to provide simple interface between various circuits with different impedance levels. • As noted previously in the common emitter (CE) configuration the input is between the base and the emitter and the output is between the collector and the emitter. (i) shows CE transistor circuit while Fig. Fungsi komponen semikonduktor ini dapat kita temui pada rangkaian PreeAmp Head , Pree-Amp Mic, Mixer, Echo, Tone Control, Amplifier dan lain-lain. Apr 25, 2020 - Transistor as an Amplifier - PowerPoint Presentation, CSE, Electrical Engineering Notes | EduRev is made by best teachers of. Another reason for using bjt cascodes is that a low voltage transistor can be protected from high collector voltages in high voltage amplifiers. An operational amplifier is an amplifier circuit with very high open loop gain and. In common emitter transistor configuration input is applied between base-emitter junction. 4 Transistor: biasing Ch. The NPN transistor has two diodes connected back to back. R 1 and R 2. The Common Collector and the Common Base con-figurations are sometimes used in the input or output stages of an amplifier when impedance matching is required. • The arrow in the symbol defines the direction of emitter current through the device. The capacitor CB is used to couple the input signal to the input port of the amplifier, and CC is used to couple the amplifier output to the load resistor RL. Common emitter configuration commonly used in low-noise amplifiers. Perform a dc analysis and hence calculate the voltage gain Av where; vo Av = vs. Emitter Degeneration • By inserting a resistor in series with the emitter, we "degenerate" the CE stage. It is worth noting that the current gain of a common-base amplifier is always less than unity. The Common-Emitter is characterized as having high input impedance and low output impedance with a high voltage and current gain. 12/3/2004 Example DC Analysis of a BJT Circuit 3/6 Jim Stiles The Univ. 9 • For the common-collector configuration, the model defined for the common-emitter configuration of is normally applied rather than defining a model for the common-collector configuration. The Amplifiers textbook describes the effects of gain, bandwidth, and distortion on amplifier performance. Fixed Base bias or Base resistor method is the basic type of transistor bias method. The voltage gain of the emitter follower is less than one, but it has reasonably high current gain. • This topology will decrease the gain of the amplifier but improve other aspects, such as linearity, and input impedance. Choose R1 and R2 to provide necessary value of VX and establish I1gtgtIB. TRANSISTOR AMPLIFIERS Common Emitter Amplifier Signal path: When a signal is applied to an amplifier, four things occur. The typical values for hFE range from 75 to 200, depending on the type of BJT. A BJT is an universal amplifier. The transistor data sheet shows variations in H FE from 100-500. In this circuit, the base of the BJT serves as the input, the collector is the output, and the emitter is common to both input and output. The input signal of small amplitude is applied at the base to get the magnified output signal at the collector. differential power amplifier delivering a power gain of 6db with high efficiency and linearity is also presented [4]. The Load Line intersects the Collector-emitter characteristic, iB = 20 µA at VCEQ = 5. Many designers view IGBT as a device with MOS input characteristics and bipolar output characteristic that is a voltage-controlled bipolar device. A common-emitter stage driving another common-emitter stage. ) • The total equivalent resistance at the base is • The total capacitance and resistance at the collector are • Because of interaction through Cµ, the two RC time constants interact, giving rise to a dominant pole. s are grouped into one of three. In the circuit diagram, there is no indication of common ground point. Combining (1) and (2), Reverse Biased. Outline • History • Theory • Amplifier mode • Switching mode Rc Common Emitter Common Base Common Collector. Draw a Darlington amplifier with Boots trap arrangement. 1) MOS and the bipolar differential amplifiers: how they reject common-mode noise or interference and amplify differential signals 2) The analysis and design of MOS and BJT differential amplifiers: utilizing passive resistive loads, current- source loads, and cascodes 3) The structure, analysis, and design of amplifiers composed of two or more. • The common-collector, with high input impedance and low output impedance, makes an excellent buffer between stages or before the output driver. Base is taken as input terminal - an input source Vs is attached to it through Rs and C1. The common-base configuration with pnp and npn transistors are shown in the figures. Reverse coupling in common-base BJTs: , Reverse coupling in common-gate FETs: , b ce g ds L C L C Some of these are device parasitics, some arise only pg from p oor interconnect design near the device terminals. Wu,UC Berkeley • Reading: Chapter •9 Review: MOSFET Amplifier Design • A MOSFET amplifier circuit should be designed to 1. Millman and A. Common-Emitter Amplifiers (with Voltage-Divider Biasing & Coupling Capacitor)- Cont. This is the origin of the nomenclature of the three types of transistor amplifiers: common collector, common emitter, and common base. Common Emitter Amps Vcc Vcc Rc Rc Rb1 Rb1 ∞ ∞ Rgen ∞ ∞ Vout Vout Vin RL Vgen Rb2 Rb2 Rgen β ib β ib Vin Rin vin Rout Vout Vgen Rin vin Rout RL Lab Circuits Common Emitter Amplifier Common Base Amplifier Common-Base Amplifier Lab experiment Multistage Amplifier HW Emitter Follower CE Resistive Feedback Common Emitter Amps Lab Circuits Common Emitter Amplifier Common Base Amplifier. • No change in the frequency of the input signal What is an amplifier? 2. T is a rough estimate of the highest frequency at which the transistor can be used as an amplifier. 17: BJT Emitter Follower Voltage AmplifierVoltage Amplifier With R L, R o should be as small as possible What if a given amplifier configuration does not have small RWhat if a given amplifier configuration does not have small R o (for example CE)? Use voltage buffer or emitter follower! Electronic Circuits 1 (09/2) Prof. electronicstek. Parameters from the spec sheet ( x = lead based on circuit configuration ): h 11 = h ix h 12 = h rx h 21 = h fx h 22 = h ox h rx and h fx are dimensionless ratios - PowerPoint PPT Presentation. Transistors have maximum values of Ic, Ib and Vce that cannot be exceeded. Clif Fonstad, 11/12/09 Lecture 18 - Slide 11. A single stage common emitter amplifier is shown in figure 1-a. Cascode amplifier is generally constructed using FET ( field effect transistor) or BJT ( bipolar junction transistor). The collector terminal is connected to the right side n-type layer. e lql Created Date: 08/15/2006 17:00:00 Title: PowerPoint Presentation Last. An amplifier that conducts for half the input cycle. 45 Common-Emitter re vs. Lecture23-Amplifier Frequency Response 5 Common-Emitter Amplifier - ωH High Frequency Response - Miller Effect (cont. An increase in base-emitter voltage V BE by about 60 mV will increase the collector current I C by about a factor. The load line is drawn by joining the saturation and cut off points. Linear Analog Amplifier. oStable and robust bias point should be resilient to variations in µ n C ox (W/L),V t (or β for BJT) due to temperature and/or manufacturing variability. h-Parameter Model. have all of the above. ¾Power MOSFETs can handle 100’s of Amps.

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