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PSoC™ 4

BhSr_4843381
Level 3
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Level 3

I am developing a current mirror circuit using the PSOC4BLE IDAC as the current source as shown in the figure. If I am supplying 100micro Ampere current, I am getting 2260micro Ampere current.

Please find the circuit in the attached image.

Can someone suggest the solution?

IMG_20210712_185211__01__01.jpg

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odissey1
Level 9
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Vasanth
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Moderator First question asked 1000 replies posted 750 replies posted
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Hi,

Could you please check the compliance votage parameter of the IDAC. Does the voltage come within the operating voltage of the IDAC in your use-case ?


Best Regards,
Vasanth

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Len_CONSULTRON
Level 9
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BhSr,

Hopefully I understood your diagram correctly.  I have a couple of issues with your circuit intention.

First Issue: You are trying to source the IDAC8 current from VSS (GND).  This is not correct.

The IDACs on the PSoC can only sink current into GND or source current from VSSA.

Second issue:  Even if you were sinking current into GND through the IDAC, you have the bias voltage at -5V.   No PSoC input or output is supposed to be less than VSS-0.5V.

Len
"Engineering is an Art. The Art of Compromise."
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odissey1
Level 9
First comment on KBA 1000 replies posted 750 replies posted
Level 9
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