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How to give DC Biasing for Two Transistor are connected feed back using ADS software

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pusparaga

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Sir,
I used the two ATF54143 transistors(Biasing Vds=3V, Ids=60mA)and connected capacitive shunt feed back and capacitor is connected between source of one transistor and drain of the other transistor. I tried to give the biasing for the two transistor, achieved the biasing for one transistor. What is my problem is , I have to get the 3V and 60mA at the drain of two transistors and some Milli volts at the gate of the two transistors, this what I desire. But I am getting ( as shown in the below figure) 3v and 0 mA at the red ring shown at #1 , 0v and 0mA at the red ring #2. Also I am getting 4.96 mv at the # 3 (as shown in the figure) and 0 mV at #4(as shown in the figure).

What I need is, I have to get 3V and 60mA(drains of the both transistor) at #1 and #2 transistors 1 and 2, similarly I have to get same Milli Volts(Gate of two transistors) at #3 and #4 of transistor 1 and 2.
I have attached two transistor feed back DC BIAS connection figure
 

Attachments

  • TWO_TRANSISTOR_BIASING_ADS.jpg
    TWO_TRANSISTOR_BIASING_ADS.jpg
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and capacitor is connected between source of one transistor and drain of the other transistor.
No it isn't. The capacitor is connected between the gate of the top transistor and ground. The drain of the bottom transistor is directly connected to the S1 source of the top transistor, with no capacitor inbetween.

Also, the S2 sources of both transistors are connected directly to ground. That can't be correct.
 
No it isn't. The capacitor is connected between the gate of the top transistor and ground. The drain of the bottom transistor is directly connected to the S1 source of the top transistor, with no capacitor in between.

Also, the S2 sources of both transistors are connected directly to ground. That can't be correct.


Sir,
I did mistake, now I have connected capacitor between bottom transistor gate and drain of the top transistor. As you said S2source of both

transistors directly connected to ground. What we need to connect the instead of ground at the other ends of two transistors. Please suggest me what we need to connect the at the gates two ends of the transistors( Because ATF54143 is having two sources,they are connected internally). Please help me to achieve 3v and 60mA at the drain of bottom and top transistor, and also some milli volts at the gate of bottom and top of transistor. For achieving this what I have to make correction . Please help me sir.
 

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  • TWO_TRANSISTOR_DC_BIASING_1.jpg
    TWO_TRANSISTOR_DC_BIASING_1.jpg
    648.8 KB · Views: 179

The second circuit still has mistakes.
- Top transistor has no gate bias
- Bottom transistor's drain and source are both connected to ground.


This webpage
has links to the ATF54143 datasheet and some application notes that explain how to use it. I hope that helps.
 
godfreyl Sir,
How I have to correct the over come these mistakes , how we can achieve same biasing for two transistors. I have gone through the data sheet, but no use for the biasing for two transistor, when use.
 

I have never used these transistors, or anything similar. Thus I can not give any detailed advice - I merely pointed out the obvious errors, and I tried to help by giving limks to relevant documrnts.
 
Dear Sir,
Some one can help to resolve how to give the biasing for feed back two transistors.
 

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