42 lines
1.1 KiB
Plaintext
42 lines
1.1 KiB
Plaintext
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Bindings for DAC emulation using a digital potentiometer
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It is assumed that the dpot is used as a voltage divider between the
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current dpot wiper setting and the maximum resistance of the dpot. The
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divided voltage is provided by a vref regulator.
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.------.
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.-----------. | |
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| vref |--' .---.
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| regulator |--. | |
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'-----------' | | d |
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| | p |
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| | o | wiper
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| | t |<---------+
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| '---' dac output voltage
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'------+------------+
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Required properties:
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- compatible: Should be "dpot-dac"
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- vref-supply: The regulator supplying the voltage divider.
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- io-channels: Channel node of the dpot to be used for the voltage division.
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- io-channel-names: Should be "dpot".
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Example:
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&i2c {
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dpot: mcp4651-503@28 {
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compatible = "microchip,mcp4651-503";
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reg = <0x28>;
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#io-channel-cells = <1>;
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};
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};
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dac {
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compatible = "dpot-dac";
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vref-supply = <®_3v3>;
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io-channels = <&dpot 0>;
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io-channel-names = "dpot";
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};
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