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Design >> Analog Design >> constant current source independent of load resistance
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Message started by umesh on Jul 27^th, 2016, 1:19am

Title: constant current source independent of load resistance
Post by umesh on Jul 27^th, 2016, 1:19am

Dear all,
I got the circuit for constant current source using op-amp known as howland current source. I have attached the circuit diagram. I got 5.2mA constant current at variable load from 10 ohm to 5k ohm. Vin is limited to 12V and expected output current should be 8mA. Please anyone suggest me what to change in this circuit so that i can get 8mA constant current.
I simulated this circuit in LTspice when i change the value of R (R1,R2,R3,R5) below 2.3k then i have getting constant current at variable load.

Title: Re: constant current source independent of load resistance
Post by vroy_92 on Jul 27^th, 2016, 11:44pm

umesh wrote on Jul 27^th, 2016, 1:19am:

Can you please post the circuit digram?