IMO calibration/accuracy

[ofric_1799416]

I found the discussion "

PSoC4 and PSoC4 BLE IMO accuracy With API-called calibration

" but it is locked.

It pointed to http://www.cypress.com/documentation/code-examples/ce97601-improving-accuracy-psoc-4-internal-main-o...

but that documentation says it is obsolete.

Is there a way to calibrate the IMO to get better than +/-2% precision

or

is there a way to know the exact frequency of the IMO even if it is within the +/-2% range so that FW can compensate for it by changing counter values?

Thanks,

Ofer

[RyanZhao]

To calibrate IMO to get a better precision, there must be another more accurate reference clock(ECO, ExtClk, which is available depend on MPN). But we may not able to modify the precision directly, we may modify count number or match value of a counter to calibrate the counter's period and duty cycle.

I think another way is easier. Users can enable IMO trim with WCO (the device must support WCO access).

https://www.cypress.com/documentation/component-datasheets/psoc-4-low-frequency-clock-cylfclk-versio...

Thanks,

Ryan

[ofric_1799416]

Hi Ryan,

" we may modify count number or match value of a counter to calibrate the counter's period and duty cycle " – this is exactly what I'm looking for.

I'm not using the WCO in my system. I'm looking for a way to do this with the ECO. I'm using the CY8C4128LQI-BL543 devices.

Thanks,

Ofer

[RyanZhao]

Hi Ofer,

You can try referring the attached project..not a project for BLE part , but could be ported easily.

It is modified based on https://www.cypress.com/documentation/application-notes/an89056-psoc-4-iec-60730-class-b-and-iec-615...

Thanks,

Ryan