Problem with analog routing when a second IDAC is used.

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
JS_4155161
Level 1
Level 1

The device is a PSOC 4200. I'm using the 8-bit IDAC for CAPsense and the 7-bit iDAC in standard configuration.

According to the resource meter, the uC has both these iDACs.

When I compile the project with just the 8-bit iDAC it works without a problem. However, when I add the 7-bit iDAC to the design, it fails to compile. The error shown is  'unable to find a solution for the analog routing' That's it. There is no further description.

What could be the problem?

0 Likes
1 Solution
Vasanth
Moderator
Moderator
Moderator
250 sign-ins 500 solutions authored First question asked

Hi,

What pins are you using as IDAC outputs ? IDAC output might need to use Amux bus resources for the output pins to be connected to IDAC. See CYDWR, analog tab and see how the outputs are routed. This will let you know what is causing the problem.

Best Regards,
Vasanth

View solution in original post

0 Likes
4 Replies
NoriTan
Employee
Employee
25 sign-ins 5 questions asked 10 sign-ins

The default setting of CapSense uses two IDACs, 8-bit modulation IDAC and 7-bit compensation IDAC.

GS004525.png

If you want to use one IDAC for an another purpose, please disable the compensation IDAC.

Because the compensation IDAC is 7-bit, You can use a 7-bit IDAC only.

GS004526.png

0 Likes

Hi, I have already disabled the compensation iDAC, so technically it should work. I have updated my question to make this clearer.

0 Likes
JS_4155161
Level 1
Level 1

Update: To make things clearer, I have disabled the compenstation iDAC, so it should be possible to include the 7-bit iDAC.

It seems however, that there is a bottleneck in the analog routing fabric, for when I removing the iDAC output pin, the analog routing is successful. Currently, I am using the ADC and the LPcomparator.

It seems that there is not enough analog routing fabric to support all these analog blocks and pins.

0 Likes
Vasanth
Moderator
Moderator
Moderator
250 sign-ins 500 solutions authored First question asked

Hi,

What pins are you using as IDAC outputs ? IDAC output might need to use Amux bus resources for the output pins to be connected to IDAC. See CYDWR, analog tab and see how the outputs are routed. This will let you know what is causing the problem.

Best Regards,
Vasanth

0 Likes