Kinetis MicrocontrollersのトピックRe: ADC0_DM0 single-ended mode in MKW38?

ADC0_DM0 single-ended mode in MKW38?

emilj — Mon, 07 Aug 2023 10:12:00 GMT

Hi,

Is it possible to use the ADC input ADC0_DM0 in single-ended mode on MKW38?
If so, how? I can't find out which ADC Channel should be selected when looking in the reference manual.

Best Regards,

Emil

Re: ADC0_DM0 single-ended mode in MKW38?

Julián_AragónM — Tue, 08 Aug 2023 16:21:33 GMT

Hi, @emilj!

Please help me checking chapter 31.2.4 Analog Channel Inputs (ADx) in the KW38's Reference Manual:

"The ADC module supports up to 24 single-ended analog inputs. A single-ended input is selected for conversion through the SC1[ADCH] channel select bits when SC1n[DIFF] is low. "

Also, chapter 31.3.1 ADC Status and Control Registers 1 (ADCx_SC1n), in ADCx_SC1n field descriptions, field 5 describes the configuration, and field ADCH selects one of the input channels:

An input is selected as Single-ended conversion when DIFF = 0.

I hope you find this helpful!

Best regards,
Julián

Re: ADC0_DM0 single-ended mode in MKW38?

emilj — Wed, 09 Aug 2023 07:09:34 GMT

Hi,

Yes, according to chapter 31.3.1 ADC Status and Control Registers 1 (ADCx_SC1n) in the KW38's Reference Manual, it seems like it's not possible to use ADC0_DM0 / DADM0 as single-ended input.

Is this assumption correct?

I found this under 31.2.5 Differential Analog Channel Inputs (DADx) in the KW38's Reference Manual:

All DADPx inputs may be
used as single-ended inputs if SC1n[DIFF] is low. In certain MCU configurations, some
DADMx inputs may also be used as single-ended inputs if SC1n[DIFF] is low. For ADC
connections specific to this device, see the chip-specific ADC information.

Re: ADC0_DM0 single-ended mode in MKW38?

Julián_AragónM — Wed, 09 Aug 2023 16:23:36 GMT

Hi @emilj,

Is this assumption correct?

Yes, this assumption is correct, when the channel is selected as a Single-Ended Input (DIFF = 0), the positive input (ADC0_DP0) is the selected input signal. This is the recommended configuration.

In order to utilize DM0 as single-ended, the channel could be selected as a Differential Input, and then connect DP0 to ground, so your input signal could be DM0.

Best regards,
Julián