Hello everyone,
I got assigened to design a voltage source that is capable supplying +-100ma at -+10V. After I build the circuit, I notice that there is some fluctuation at the output side. I probed with scope and there is no oscillation at the gate or opamp. The Vref into the opamp is extremely stable 0.70160X volts. but my output fluctuates around 1mv. The mosfet is FR5305. I need some advise on getting this thing more stable....
Thank you!
Update 1. Yes.. I draw the arrow on mosfet backwards
Update 2. It cannot sink current... but I don't know how to do push pull since it will turn both transistors on in the middle region..
I got assigened to design a voltage source that is capable supplying +-100ma at -+10V. After I build the circuit, I notice that there is some fluctuation at the output side. I probed with scope and there is no oscillation at the gate or opamp. The Vref into the opamp is extremely stable 0.70160X volts. but my output fluctuates around 1mv. The mosfet is FR5305. I need some advise on getting this thing more stable....
Thank you!
Update 1. Yes.. I draw the arrow on mosfet backwards
Update 2. It cannot sink current... but I don't know how to do push pull since it will turn both transistors on in the middle region..
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