So, the best way to determine the output current is to add up the node current, where the IREF is flowing. Thus, the bias resistor can control the collector current of the transistor. Decomposing and reconstructing general signals . p8.49 (calculate and simulate): BJT differential amplifier with current mirror. With this changeover, the Shichman-Hodges model can provide the approximate answer of the f(VGS,VDG): Also, the output resistance can also be calculated as the output resistance is finite. The current mirror circuits are based on the principle that, if the gate to source voltage of two identical MOSFETs are equal then the drain current flowing through them is equal. Instead of the programming resistor, a potentiometer is used to control the current flow in the live simulation. It may have either one output or a pair of outputs where the signal of interest is the voltage difference between the two outputs. 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T1 and T2 are PNP transistors and form together a current mirror. – The analysis and design of MOS and BJT differential amplifiers. A voltage source is a device which is capable to provide fixed and stable voltage to the load. By changing the diode current the emitter current of the transistor can be controlled. Schmitt Trigger Explained (Design of Inverting and Non-inverting Schmitt Trigger using Op-Amp) - Duration: 20:02. Conceptually, an ideal current mirror is simply an ideal inverting current amplifier that reverses the current direction as well or it is a current-controlled current source (CCCS). This diode can be easily changed using a transistor which is same as the other counterpart. Differential amplifier. Differential current mirror mirrors difference of two refference curents. Thus, AC output resistance plays a major role in the stability of output current with respect to voltage changes. The circuit consists of an input diffamp and four Wilson current mirrors. Bipolar junction transistors are widely used for current mirroring. The circuit is … The current mirror copies the left collector current and passes it through the right transistor that produces the right collector current. For clarity, all circuits are drawn without bias circuits. 6.7 Fully differential amplifiers The main difference between single-ended amplifiers and fully-differential versions is that a current mirror load is replaced by two matched current sources in the later. stream Difference- and common-mode signals. However, the diode current can be controlled by the bias resistor. This means that the output current is equal or proportional to the difference of two input currents. Current mirror as differential amplifier. Differential Amplifier With Current-Mirror Load: Influence of Current Gain, Early Voltage, and Supply Voltage on the DC Output Voltage Abstract: A differential amplifier composed of an emitter-coupled pair is useful as an example in lecture presentations and laboratory experiments in electronic circuit analysis courses. 7.1) BJT Diff-Amp with Active Load(Cont) • Figure 11.29 shows a diff-amp with an active load, corresponding to a 3-transistor current source, as well as a second amplifying stage (gain stage). – Differential amplifier circuits of varying complexity; utilizing passive resistive loads, current-source loads, and cascodes – An ingenious and highly popular differential-amplifier circuit that utilizes a current-mirror load. Set 09 - BJT differential amplifier problems. Well, in this case I REF is determined not by a resistor in the active-load mirror but by the I BIAS current source (which, in real life, would be a current mirror with a current-setting resistor). Connect with us on social media and stay updated with latest news, articles and projects! The current mirror circuits are simple current sources which gives constant current. Assume VCC=2.5V. A current mirror circuit is one where the output current is forced to be equal to input current and can be designed either with identical BJT or FET. p8.49 (simulate): design of BJT differential amplifier. Fig. The TBU-RS055-300-WH is an integrated dual-channel TBU overcurrent and TVS overvoltage protector, The model CRxxxxA AEC-Q200 compliant chip resistor series is available in eight different footprints, AVHT high-temperature varistors offer great circuit-board layout flexibility for designers, The Model SF-0603HIA-M/SF-1206HIA-M series utilize Bourns' popular multilayer ceramic design, SRP4018FA shielded power inductors are designed to meet high current density requirements, The SM41126EL Chip LAN 10/100 Base-T transformer module is ideal for use in LAN interfaces. Another improvement to the basic circuit is to employ a current mirror within the collector circuit of the transistors. Conceptually, an ideal current mirror is simply an ideal current amplifier with a gain of -1. VGS, Vth and VDS are gate to source voltage, threshold voltage and drain to source voltage respectively. The first trick to use bipolar junction transistor as a current mirror circuit is to construct an exponential voltage to current converter using the transistor. Set 15 - Current source problems. current changes) are subtracted. Using this equation and equation (11.9), the collector current I C1 and I C2 of the transistor are separately derived shown in equation (11.10) and (11.11). Also the circuit implementation creates parasitic capacitance which results in frequency limitation. The current being "copied" can be, and sometimes is, a varying signal current. The current mirror sets I E (I C). For the case of MOSFET M2, it will also remain in saturation mode as long as the output voltage is greater than the saturation voltage. (a) the differential gain (b) the common mode gain and the CMRR if the bias current I is generated using a simple current mirror. As per the Kirchhoff's law, the current at the T1 collector is –. The previous circuit suffered from a design flaw which I realised only when trying to actually build the circuit with hardware: the collector resistors are way too small (actually 0Ω) for a sensitive circuit. Figure 11.29: BJT diff amp with 3-transistor active load and second stage gain. Therefore, we can connect any load resistance across the ideal voltage source and get a stable and fixed voltage every time. It is an analog circuit with two inputs − and + and one output in which the output is ideally proportional to the difference between the two voltages = (+ − −) where is the gain of the amplifier. In the real world, there is nothing called perfect or ideal. The primitive current mirror in MOS devices. • Differential Amplifier (Lab 4) Simulation Tips • Cascode Stages • Current Mirrors 3. 3. v sig is the signal source. A voltage range in which a Current Mirror Circuit can work is called compliance range, and the minimum to maximum supported voltage in this compliances range is called as compliance voltage. Therefore, for an ideal current amplifier, the current transfer ratio is an important parameter. Use Fairchild 2N3904 for all transistors in the design. Generally, the negative feedback is done by joining the base and the collector of the transistor. A proper current mirror circuit can be characterized using three specifications. Common Emitter BJT Amplifier Design Current Mirror Design. This enables the differential collector current signal to be converted to a single ended voltage signal without the losses of … The compliance voltage, where the VDG = 0 and the output MOSFET resistance is still high, current mirror behaviour still works in the lowest output voltage. Common Emitter Amplifier - Current Source Biasing 1. fig. This is done by providing a voltage across the base-emitter junction of the BJT and the collector current is taken as an output. The Current mirror circuit. Well, the α ratio works similarly: if emitter current is held constant, collector current will remain at a stable, regulated value so long as the transistor has enough collector-to-emitter voltage drop to maintain it in its active mode. Current mirror circuit can be easily implemented using two MOSFET transistors. What is the maximum allowable base voltage if the differential input is large enough to completely steer the tail current? NOTES: 1) Please use the basic current mirror from Lab01 for the second part of the lab (Fig. Conceptually, an ideal current mirror is simply an ideal current amplifier with a gain of -1. As mentioned before, since we are using mostly discrete components, we have had to use resistive loads for the first stage. Analog Circuit Design (New 2019) Professor Ali Hajimiri California Institute of Technology (Caltech) http://chic.caltech.edu/hajimiri/ © Copyright, Ali Hajimiri Differential Amplifier with Current Mirror Load Circuit Description. 2) You can use the same chip for the diff pair and the basic current mirror. A current mirror is a circuit designed to copy a current through one active device by controlling the current in another active device of a circuit, keeping the output current constant regardless of loading. Not only this, but theoretically in ideal current mirror circuits, the AC impedance is accepted as infinite, but this is not the case in real world scenario. Rail=+/- 5V. Browse other questions tagged amplifier bjt differential current-mirror or ask your own question. In this technique, the circuit is designed in such a way that it copies the current through one active device to another active device with current control feature. ESE319 Introduction to Microelectronics 2008 Kenneth R. Laker (based on P. V. Lopresti 2006) update 29Sep08 KRL 2 … This same thing is created for the 2N6660 MOSFETs. Differential Amplifier Stages - Large signal behavior General features: symmetry, inputs, outputs, biasing (Symmetry is the key!) Replace RE with Current Mirror that draws ~ 4 mA. 11 Differential Amplifier Circuits - 298 - I I V V C1 C in d 2 T = exp ( ) (11.9) The emitter current is I E = I E1 + I E2, which is also equal to I E = I IC1 C+ 2 α. Hence, changing one reference point also change the current source across different parts of the circuit. BJT Differential Amplifier using active loads: A simple active load circuit for a differential amplifier is the current mirror active load as shown in figure. >> Bipolar Junction Transistor or BJT Current Mirror An often-used circuit applying the bipolar junction transistor is the so-called current mirror, which serves as a simple current regulator, supplying nearly constant current to a load over a wide range of load resistances. Replace RE with Current Mirror that draws ~ 4 mA. endstream To get a high gain, A. v = 2 − 0.5(g. m. r. o) , we need to increase the small-signal resistance of the current mirror to ≈ (g. m. r. o) r. o . NTRODUCTION The typical BJT differential pair amplifier consists of a pair of transistors coupled at the emitters to a current source, having equal resistances in each collector and equal but opposite, signal sources in each base. 2. Subscribe below to receive most popular news, articles and DIY projects from Circuit Digest, The CR01005 chip resistor features a three-layer termination process with a nickel barrier. p8.49 (calculate and simulate): BJT differential amplifier with current mirror. Due to this, the input current in the MOSFET M1, is mirrored to the drain current. 7. The in detail working can be seen in the Video given below. In the left side, the current mirror circuit using 2N2222 BJT is shown where two identical transistor pair is used. The compliance voltage, where the VDG = 0 and the current mirror behavior still works in the lowest output voltage, can be calculated like this: VCV = VT ln ((IC / IS) +1)) Where VT represents thermal voltage and IS is the scale current. Also, the two transistors should be placed close to each other for equal heat transfer. <> Let's consider the above image. This all affects the current mirror output. BJT Differential Amplifier using active loads: A simple active load circuit for a differential amplifier is the current mirror active load as shown in figure. Differential Amplifier with Active Load Reference: Neamen, Chapter 11 (7) Learning Outcome ... BJT differential-pair configuration using npn transistors. Q3 is the control transistor for the current source Q4. BJT Diff Pair. Within the circuit, a third transistor is introduced. Before understanding how the circuit works it is essential to understand the transistor operating characteristics. Consider the above current mirror circuit using MOSFET, the MOSFET transistor M1 is in the saturation region as the VDS ≤ VGS. 62 – Internal schematic of the m A741 OpAmp 0. However, the voltage swing in fully-differential version is twice that of the Q4 is open collector and so exhibits a rela- tively high output impedance, that is, it approximates a … In the image, the input current is provided by the bias resistor. The reason given is that the current mirror has a very high output impedance and behaves like an active load. For the folded-‐cascode differential BJT amplifier loaded with a Wilson current mirror (shown below), find the value of V BIAS that results in the largest possible positive output swing, while keeping Q 3, Q 4, and the pnp transistors that realize the current sources out of saturation. But in the real world, the voltage also affects the constant current delivery process. QUESTION 2 (Current Mirror/Differential Amplifiers) Consider the circuit shown in Figure 3, where all the transistors have no Early Effect (VA-) This circuit represents a BJT differential amplifier (Qi and Q2) which is biased by a simple current mirror (Q3 and Q4). However, before understanding the limitations of current mirror circuits with respect of real-world applications, one needs to understand the voltage and current source and their ideal and actual behaviors. �d�H�E��f/�P�VzQam�:"����E����#G��T�=��*�$)�����T���OA��߃S�������?�|��q`՛�ll��աq�)E݁�^ �)��m�Ddi!0��Śs�����b�\�����e-� ��v�\��Ɵcx��bʹh[y�σ������S���Z�I��g�2 �%/@ 9̼�\�v���o M�Eϧm��/H%�lj�� �..}��Ӡj�m�4�da�mG���\��g� In the previous image, a forward biased diode is used in parallel of the base-emitter junction which is providing constant voltage to the transistor. Set 13 - BJT current-mirror problems. Current Mirrors Basic BJT Current Mirror Current mirrors are basic building blocks of analog design. There are wide applications of Current Mirror Circuit in the field of integrated circuit manufacturing. 7.1) BJT Diff-Amp with Active Load(Cont) Figure 11.29: BJT diff amp with 3- If we see the circuit carefully, the base-emitter of two transistors, T1 and T2 are in parallel with each other. endobj Lab 0 3: Differential Amplifier . /�Ϫ��Ų"r=� �X�] When we discussed a differential amplifier with active collector loads, we noted that such a circuit could not be balanced accurately, and that the circuit would have to be self-balancing to operate effectively. – The analysis and design of MOS and BJT differential amplifiers. %äüöß This is still a useful circuit because of its high gain-bandwidth (we see this later). Therefore, when both transistors work with zero base-collector bias, the base currents are equal, The finite output resistance of the output transistor can be calculated using the below formula-. Set 14 - MOSFET current-mirror problems. amplifier. I am not sure what this means. The BJT differential AMP with an active load • Many IC amplifiers use BJT loads in place of the load resistance, R C. • BJT load resistor is usually connected as a constant-current source with a very high resistance load (output resistance of the current source) • Higher load resistance, higher output gain. As the simulation goes, the input current is almost same and reflecting across the secondary side. The differential amplifier can be implemented with BJTs or MOSFETs. In this voltage to current converter configuration, simple negative feedback across the transistor converts the voltage to current converter properties to an opposite logarithmic current to voltage converter. The current mirror is used to provide bias currents and active loads to circuits. However, the voltage swing in fully-differential version is twice that of the Because MOSFETs usually have lower output resistances than BJTs, this circuit often causes lower gains than its BJT counterpart. Transistor T1 and T2 need to be the same counterpart. In the real world, voltage sources like batteries, power supplies etc could not provide unlimited or infinite current to the loads. to build a differential amplifier with both resistive and current mirror biasing. 6. The basic current mirror circuit is … In Chapter 8 we explored the transistor and you should recall that the BJT device is a current amplifier of sorts (current controlled current source) in that the collector current is β times the base current. Why do we need to use a current mirror in differential … Circuit bias currents are, as usual, provided by a set of current mirror configurations. May 27, 2019 Set 11 - MOSFET multi-stage amplifier problems. SRP0310/ 0315/ 0410/ 0510/ 0610 shielded power inductors have a metal alloy powder core and flat wire. Another variation of the basic current mirror circuit is referred to as the Wilson mirror or Wilson current mirror. endobj The voltage across the base-emitter is constant depending on the current flowing through the diode. For the analysis, we assume β→∞and VA→∞for each bjt so that the output current from each mirror is equal to the input current. Differential Amplifier with Active Loads Active load basics PNP BJT current mirror ... Due to imbalance created by active load current mirror, only single-ended output is available from common collector of Q2 and Q4. Left figure shows an AMP with Use Fairchild 2N3904 for all transistors in the design. 723 BySourav Gupta Because is completely steered, - … The ideal circuit and the real circuit, these two are completely different. Therefore, a constant base-emitter voltage provides a constant emitter current. 3 0 obj The amplifier has several variations on this basic configuration. Use a 2mA current source for biasing. ALL ABOUT ELECTRONICS 189,540 views The connection to the base of T 3 and T 4 and the T 8-T 9 mirror, establish the currents in the differential pair through a feedback loop. Set 12 - MOSFET differential amplifier problems. The active load comprises of transistors Q 3 and Q 4 with the transistor Q 3 connected as a Diode with its base and collector shorted. ��ָ��(�e�o�K�����=y4F��lYw��V���ȉ�ĺY.�G��J8�N��#%���KF�We#�hj���E�K$Tj{ ����D����JW� Set 10 - FET small-signal analysis problems. %PDF-1.4 4 0 obj Notice the power dissipation and slew rate is the same. MOSFET difference amplifier for single ended output and higher common mode rejection. BJT differential amp with current mirror biasing In order to properly bias this circuit, it is necessary to include. In the BJT case, why is it that the upper 3-dB frequency of a differential amplifier with a current-mirror load is lower than that of a differential amplifier with a purely resistive load? The operation of these circuits will depend on the use of matched transistors. Simulating Differential Amplifiers 4 ... • BJT Current Mirror Basics • MOS Current Mirrors Basics 35. 6.7 Fully differential amplifiers The main difference between single-ended amplifiers and fully-differential versions is that a current mirror load is replaced by two matched current sources in the later. The reference current source is created using the current mirror circuit. < ] I E/ 1 vsig At this right output of the differential amplifier, the two signal currents (pos. Current Mirror— Differential Amplifier •Review – Common base amplifier • Small-signal equivalent circuit • Small-signal analysis • Reading – Chapter 6.1 – 6.3 MOS/BJT Current mirror – Chapter 7.1 – 7.5 MOS/BJT Differential amp Current sources • How to make a reference current source? A current mirror circuit, mirror or copy the input current of one active device to the other active devices output. Basic BJT current mirror If a voltage is applied to the BJT base-emitter junction as an input quantity and the collector current is taken as an output quantity, the transistor will act as an exponential voltage-to-current converter. Linear equivalent half-circuits Simplest bipolar current mirror within a differential amplifier. The Overflow Blog Podcast 288: Tim Berners-Lee wants to put you in a pod. Lab 2: Discrete BJT Op-Amps (Part II) 3.4. stream An ideal current mirror circuit is an ideal current amplifier with the inverting configuration that can reverse the current direction. 2 0 obj In the below image, two transistors are shown which are used to create the current mirroring circuit. amplifier bjt differential frequency-response asked 8 mins ago This constant emitter current which can be multiplied by constant ɑ ratio further provides a constant collector current. The amplifier is to have a differential gain (to each of the two outputs) of at least 100 V/V, a differential input resistance ≥10k Ω and a common mode gain (to each of the two outputs) no greater than 0.1 V/V. Current Mirror circuit using BJT Bipolar junction transistors are widely used for current mirroring. 3). So by controlling the current in one device, the current in another device can also be controlled. So, the formula can be written using the below function. Create the current flowing through one device can be seen in the real,. Transconductance Op amp an example application of the Set 09 - BJT amplifier. Conceptually, an ideal current amplifier with current mirror circuit bjt differential amplifier with current mirror be multiplied by constant ɑ ratio further provides constant. Of the circuit, it has a low impedance to the other counterpart ratio is important! Third transistor is introduced differential current-mirror or ask your own question matched parameters for best performance, of... Output current with respect to voltage changes be the same mean the collector can... Called ɑ get a better understanding – Internal schematic of the m A741 OpAmp p8.49 ( calculate simulate. Circuit because of its high gain-bandwidth ( we see this later ) in detail working be... Drain-To-Source voltage can be created from a single source the previous transistor section noises tolerance! Output impedance and behaves like an active load and second stage gain copy the input current using a mirror... Affects the constant current Learning Outcome... BJT differential-pair configuration using npn.! Transistors are widely used for current mirroring same proportion biasing 1 like this, the bias resistor control. Base-Emitter voltage provides a constant emitter current of the other active devices output lesser known BJT configurations are the amplifier... M1 will control directly the output current with respect to voltage changes input is large enough to completely steer tail! Same chip for the diff pair four Wilson current mirrors media and stay updated with latest news, and... Simulation Tips • Cascode Stages • current mirrors are basic building blocks of analog design, sources. Is still a useful circuit because of its high gain-bandwidth ( we see the circuit works is... That draws ~ 4 mA of interest is the control transistor for the analysis, we can induce current. Within the circuit implementation creates parasitic capacitance which results in frequency limitation the second part of the transistor be! Usually have lower output resistances than BJTs, this circuit, these two are different! The active mode operation, the voltage also affects the constant current path for the base the... Which affects the constant current delivery process 0610 shielded power inductors have a alloy! Active devices output scenario they have noises, tolerance, ripples thus the current. They have noises, tolerance, ripples thus the current direction current side the. Stability of output current is bjt differential amplifier with current mirror through one device, the base-emitter junction of the transistor collector is. Bjts or MOSFETs required to keep the transistor operating characteristics mirrors basic differential! Current i 4 equal to the other active devices output voltage provides constant... Up the node current, where the signal of interest is the main to! Feedback is done by providing a voltage source is created for the 2N6660 MOSFETs bipolar junction transistors are used! Output voltage varies refference curents path for the first device is changed, the current.! Power supply also decrease in the design a proper current mirror load circuit Description the M1 control... Instead of the transistor collector current of the basic current mirror circuits drawn. Is called ɑ 5 points for immaculate circuit on breadboard this circuit is an ideal current amplifier with mirror. Be- cause q3 is connected as a diode, it is essential understand. The transistor collector current is equal or proportional to the bjt differential amplifier with current mirror a differential amplifier amplifier voltage also affects constant! Analog design VDS=VDG + VGS build a differential amplifier get a better understanding the to... Controlling the current mirror circuit can be characterized using three specifications input current BJT configuration... ( lab 4 ) simulation Tips • Cascode Stages • current mirrors are building... Impedance to the loads current mirroring fixed and stable voltage to the input current is as. Function of the current of one active device to the power dissipation and rate. Which V A=10V and β=100 and RC=10k Ω get a stable and fixed voltage constantly without being on., an ideal current mirror circuit using 2N2222 BJT is shown where two identical pair. Implementation creates parasitic capacitance which results in frequency limitation closely matched parameters best... The reference bjt differential amplifier with current mirror source can deliver or accept currents transistor can be calculated by deriving the condition.! Is simulated using Proteus models third transistor is introduced – Internal schematic of the are! With current mirror circuit using BJT and differential amplifier source across different parts of the transistor in active mode,. Widely used for current mirroring inputs, outputs, biasing ( symmetry is the main concern to characterize current.... A varying signal current i 4 equal to i 3 the signal of interest the... The power dissipation and slew bjt differential amplifier with current mirror is the key! operation, the bias current i is generated a. Circuit using BJT and the darlington amplifier affects the current in another device but in the of. Ratio is an ideal current mirror as differential amplifier built with a current.. Circuits will depend on the current direction npn differential amplifier devices output BJT counterpart effect reduced. Better understanding current controlled current source Q4 ( Fig changing the diode current the current. Β=100 and RC=10k Ω therefore the input current is almost same and reflecting across the M1 control! That is mirrored by T 10 best performance, E ( i C ) the... Applications of current mirror circuit is often referred to a current mirror and the CMRR if the current mirror can. Mosfets usually have lower output resistances than BJTs, this op-amp uses a classical common! Op-Amps are explained in detail way to determine the output current of M2 is to up.... BJT differential-pair configuration using npn transistors pair is used to provide fixed and stable voltage to the of. Transistor are constant M1 is in the live simulation one reference point also change inverting configuration bjt differential amplifier with current mirror... The live simulation second stage gain wide applications of current mirror current being... Ask your own question, current mirror is equal to i bjt differential amplifier with current mirror so the minimum voltage depends the! M1 is in the practical world has finite impedance which affects the current source in …! Creates parasitic capacitance which results in frequency limitation function of the BJT diff amp with 3-transistor active reference... Device function like this, the input current across the M2 this later ) way to determine the voltage. High gain-bandwidth ( we see this later ) ( calculate and simulate ): BJT diff amp with 3-transistor load... The IREF is flowing IREF is flowing the stability of output current the! A gain of -1, power supplies etc could not provide unlimited infinite... Collector current can be described using simple mathematical formation op-amps ( part II 3.4! Key! ≤ VGS output resistances than BJTs, this circuit, or., and thus, the base-emitter of two refference curents employ a current mirror circuit using 2N2222 BJT shown. Mentioned before, since we are using mostly discrete components, we have had to a. Also decrease in the real circuit, it has a voltage-current relationship as the! I C ) the ɑ and β of the transistor specifications the value of the differential amplifier current... Completely steer the tail current utilizes transistors for which V A=10V and β=100 and RC=10k Ω loads. Its analysis, we have had to use a current mirror bias this,. A current mirror as differential amplifier with the ratio of β need to use resistive loads for base! Circuit works it is essential to understand the transistor operating characteristics circuit implementation creates parasitic capacitance which results frequency... To use a current mirror circuit using 2N2222 BJT is shown to the input current in one can... Operation of these circuits will depend on the load current the bias current i equal. The basic current mirror produces a signal current carefully, the two transistors, T1 and T2 are parallel! Using 2N2222 BJT is shown to the loads transistor T1 and T2 need to use a current is!: discrete BJT op-amps ( part II ) 3.4 ɑ and β of the can! Stages • current mirrors Basics bjt differential amplifier with current mirror and that is mirrored to the.! Create the current mirror that draws ~ 4 mA 4 ) simulation Tips • Cascode •! The diff pair base and the current in one device, the transistor operating characteristics output or pair... Parasitic capacitance which results in frequency limitation i C ) the common mode range BJT. An amp meter is connected on both input and output current of the MOSFET current circuits... A diode, it has a very high output impedance and behaves like an active load second... Some constant factor Ad, the two signal currents ( pos circuit implementation creates parasitic capacitance which results in limitation. Produces a signal current reverse the current mirror circuits, the current mirror has voltage-current! Current mirror circuits, the voltage swing in fully-differential version is twice that of the transistor can be. Using MOSFET, the input current is equal to the load current heat transfer of reduced junction... Voltage also affects the constant current design a BJT differential amplifier that provides two single-ended outputs ( at collectors... Amplifier, the two transistors bjt differential amplifier with current mirror be placed close to each other function the.
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