IDAC_SetValue() doesn*t work

[TaGe_4284161]

Hello Community,

i tried to measure the voltage with a multimeter at a resistor with 100 ohm. So I set my IDAC with different Values( from 0 to 0xFF) and it always shows me the same Voltage instead of different Volatge at the measurement point. The Measurement point is at Rref!

Thank you

Tak

[Vasanth]

Hi Tarik,

Could you please share your project ? In PSoC Creator ,  go to File -> Create Workspace Bundle -> Select minimal. Please attach the generated file.

Meanwhile also make sure that you are below the IDAC compliance range as said in this KBA.

Best Regards,
Vasanth

[NoriTan]

Did you _Start() the IDAC component?

Regards,

Noriaki

[TaGe_4284161]

Yes, i started. I upload my Project

Thanks

[Vasanth · Accepted solution]

Hi Tarik,

How are you trying to measure the current ? I tested your project after keeping a break-point on line 107 where Ref IDAC channel is taken selected and IDAC_SetValue(0xff);. In debug, I was getting right output on pin 3[4].

Best Regards,
Vasanth R S

[TaGe_4284161]

Hi Vasanth,

as you see in the picture. The blue pin is my REF_Current, black is ref_negative, red is ref_positive, and the other black is tothe ground.

I measured the voltage from the blue resistant as you see. The resistant has 100 ohm. I always measure 112 mV. And as you mentioned the first run through (when I debug) shows me an different Voltage measure, but the following run through shows me again the 112.

Best Reagrd Tarik

[TaGe_4284161]

I think the Problem is the Mux, if I delete the Mux and just connect the IDA with my Ref_Resistor, I get a higher Voltage measurement af REF.

[Vasanth]

Hi

The project as such does not seem to have any problem. If you are measuring the voltage in the loop you will not get right voltage. You can keep a break-point after setting the value on IDAC and measure the voltage. That should give the right value. Also make sure IDAC compliance is met as stated in 2nd response.

Best Regards,
Vasanth

[rola_264706]

Your meter may be loading the circuit what kind of meter are you using?