I have been trying to hook up ADE7758 with STM32F401, but I am having a problem understanding the frequency part of it.
There is no minimum or maximum frequency for SPI CLK in the datasheet, and my SPI on the STM32 is set at 84 MHz.
It only states the SCLK which is a range of frequency for the external oscillator that we need to attach with the circuit.
Do both master and slave need to have the same frequency? or should one be more than or less than the other?
I have searched the internet before posting a question here.
Best Answer
From Table 1 - Specifications, the maximum, minimum, and typical SPI frequencies are given. I say typical, as that's what they have used for characterisation in the datasheet so it will be guaranteed to work as specified under those conditions (not accounting for external factors, such as interference etc).
The ADE7758 does not generate an internal SPI clock, so it is solely dependent on the STM generated clock. If you are generating a nominal 10 MHz clock, that happens to be 10.25 MHz if you don't have fractional clock dividers, it will be absolutely fine. Generally speaking, aim for the typical value then stick well within the absolutes.