LPSPI Voltage Levels

Psabouri — Wed, 26 Oct 2022 08:05:30 GMT

Hi,

I am having trouble interfacing S32K344 LPSPI with TMS570 mibSPI. What is the VIH, VOH, VIL, and VOL for S32K344 LPSPI SCK, CS, SOUT, and SIN pins?

Thanks,

Pouya

Re: LPSPI Voltage Levels

davidtosenovjan — Thu, 27 Oct 2022 11:01:14 GMT

It is given by use power supply rail and its configuration (5V or 3.3V). LPSPI pads can be on both supply levels, either VDD_HV_A or VDD_HV_B (pay attention to excel sheet S32K344_IOMUX.xlsx, embedded in the device’s RM).

VIH/VIL you will find defined in DS, Table 22 and 23.

VOH/VOL I have found it only indirectly stated within IOH and IOL specification as condition for this current measurement.

For instance for IOH_33 condition is VOH >= VDD_HV_A/B - 0.7V

It means V-I characteristic of the pin can be estimated by linear approximation between points and < IOH_33; VDD_HV_A/B - 0.7V> and <0mA ; VDD_HV_A/B>.

The same way IOL_33 condition is VOL <= 0.7V.

It implies V-I characteristic as < IOL_33 ; 0.7V > and < 0mA ; 0V >

However it is expected that SPI output lines and connected to high impedance input, so you can just simplify it to expect VOH = VDD_HV_A/B and VOL = VSS (i.e. 0V).

topic Re: LPSPI Voltage Levels in S32K

LPSPI Voltage Levels

Re: LPSPI Voltage Levels