CCMP25-DVK Vref+ Pin at 0V

Embedded Devices Linux
1

I am using DEY 5.0. I have made my own custom machine based on the ccmp25-dvk. I made a modification to the devicetree to use an internal reference instead of the external for the ADC (see snippet below). I was expecting the reference voltage to be output on the Vref+ pin. However, when I read it using a DMM, I got 0V. The ADC conversions appear to give accurate results (i.e., produced correct readings when applying a known voltage).

&adc_12 {

    /\* External Vref (requires connecting external voltage to VREF+ pad) \*/

    //vref-supply = <&external_vref>;

    /\* Internal Vref (this outputs VREFBUF voltage at VREF+ pad) \*/

    vref-supply = <&scmi_vrefbuf>;

    vdda-supply = <&scmi_vdda18adc>;

    pinctrl-names = "default";

    pinctrl-0 = <&ccmp25_adc_pins>;

    status = "okay";

Are there any other changes that are needed to the devicetree to support the Vref+ pin?