How to use the CC function of eTPU?

[CatwitCh]

Hi Everyone, I am trying to drive a valve by using eTPU functions. The main purpose is to control the duty cycle of PWM signal loaded on the valve with current control.

My way is to control PWMMDC function to output a PWM signal, which is adjusted by CC function with a ASDC function measuring current, however it did not work.

Does ASDC function need a external AD converter? or it has internal AD converter? or can I use eQADC module instead?

I have also checked the ASAC function, it seems have bit relationship with eQADC, but it confused me about how to link the eQADC and eTPU.

Appreciate your help, it would be better to example codes.

[petervlna · Accepted solution]

Hello,

None of the eTPU functions works directly with ADC. Trigger functions for measurement of analog values  as ASDC or ASAC are generating configurable trigger pulses. Which are possible connect to ADC and start the measurement.

You should separately configure ADC, eTPU does not have any internal ADC, it is pure digital IP.

These trigger functions can be used for processing of measured values, for example filtration, DC offset..
Here is a list of application notes for the functions you are mentioning:

AN2840 - DC Motor control PWM function

​AN2844 -  using Current Controller function

​AN2958 - using DC Motor Control eTPU Functions

AN2846 - using ASDC function

Here is full example project:
https://www.nxp.com/docs/en/application-note/AN3008.pdf

attached is the SW code.
best regards,
Peter

[johndiener]

A different application and a fairly old example, but it does demonstrate using eQADC and eDMA with the ASDC function - AN3008 (attached).