topic S32 Series MCU : Difference between ADC Precise Input and ADC Standard Input in S32K

S32 Series MCU : Difference between ADC Precise Input and ADC Standard Input

Sreelakshmi — Fri, 03 Nov 2023 13:33:31 GMT

Dear Team,

While referring the S32 series MCU IO Mux sheet, I could see that some ADC Inputs are described as ADC Precise Input and some as ADC Standard Input.

What is the difference between the two?

Regards

Sreelakshmi A

Re: S32 Series MCU : Difference between ADC Precise Input and ADC Standard Input

VaneB — Fri, 03 Nov 2023 18:35:00 GMT

Hi @Sreelakshmi

The precision channels have fewer parasitics than standard channels. The external channels are channels using an external analog mux supported by the ADC. Most parasitics are dominated by the external circuit (varied by the design).

Also, the precision channels have a capacitance of 0.57pF (ADC0), 1.34pF (ADC1), and 1.32pF (ADC2). The standard channels have 4.18/4.13/4.03pF respectively.

Another important consideration is the TUE, reported in the DS is equal for all channel types (Precision Standard and External).

The DS specification: Typ TUE(+/-4 LSB) and Max TUE(+/-6 or +/-8 LSB depending on condition) applies to all channel types (Precision Standard and External), but is important to take into consideration that the specifications apply only to the MCU (The accuracy dropping for an external MUX component needs to be considered a part of the S32K3xx DS).

B.R.

VaneB

Re: S32 Series MCU : Difference between ADC Precise Input and ADC Standard Input

Sreelakshmi — Fri, 01 Dec 2023 10:38:31 GMT

Hi Vane,

Thanks for the details.

I would also like to know the difference between External ADC Input Pin.

How is it different from Precise and Standard ADC Input Pins.

Regards

Sreelakshmi A

Re: S32 Series MCU : Difference between ADC Precise Input and ADC Standard Input

VaneB — Mon, 04 Dec 2023 18:28:39 GMT

Hi @Sreelakshmi

Please check the following link. There is information related to the topic you might find useful.

S32K3 ADC Use of external channels