Hi,

I'm trying to perform a DC analysis on a single ended output differential amplifier (I've uploaded an image of the circuit) and I'm having problems calculating the collector voltage and current of transistor 2. So far I've calculated the tail voltage and current. My calculations are as follows:

(It = tail current source)

It = V/R = 10V / 4.7KΩ = 2.13mA

Taking into account It= IE1 + IE2

Therefore IC2 = IE2 = It/2 = 1.06mA

Therefore VC2 = +Vcc - (IC2.R1) = 5.02V

I require VC2 and IC2 in order to complete the DC analysis of the rest of the circuit (not shown in the picture) as a single-ended output is taken from this point. When I add a probe on multisim and perform a simulation it is telling me that VC2 = 6.02V and IC2 is 0.846mA. I can only assume that this is due to the fact that the output is taken from the 'side' of the differential amplifier that contains a resistor whereas the other 'side' doesn't, therefore making VC1 and IC1 different to VC2 and IC2. I don't know however how to factor this into my calculations and if anyone could help me find out how to get the proper values (the ones I got from the simulation) it would be much appreciated!

(B>1 therefore the base current of each transistor can be ignored)

I'm trying to perform a DC analysis on a single ended output differential amplifier (I've uploaded an image of the circuit) and I'm having problems calculating the collector voltage and current of transistor 2. So far I've calculated the tail voltage and current. My calculations are as follows:

(It = tail current source)

It = V/R = 10V / 4.7KΩ = 2.13mA

Taking into account It= IE1 + IE2

Therefore IC2 = IE2 = It/2 = 1.06mA

Therefore VC2 = +Vcc - (IC2.R1) = 5.02V

I require VC2 and IC2 in order to complete the DC analysis of the rest of the circuit (not shown in the picture) as a single-ended output is taken from this point. When I add a probe on multisim and perform a simulation it is telling me that VC2 = 6.02V and IC2 is 0.846mA. I can only assume that this is due to the fact that the output is taken from the 'side' of the differential amplifier that contains a resistor whereas the other 'side' doesn't, therefore making VC1 and IC1 different to VC2 and IC2. I don't know however how to factor this into my calculations and if anyone could help me find out how to get the proper values (the ones I got from the simulation) it would be much appreciated!

(B>1 therefore the base current of each transistor can be ignored)