42 lines
977 B
Plaintext
42 lines
977 B
Plaintext
Current Sense Shunt
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===================
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When an io-channel measures the voltage over a current sense shunt,
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the interesting measurement is almost always the current through the
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shunt, not the voltage over it. This binding describes such a current
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sense circuit.
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Required properties:
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- compatible : "current-sense-shunt"
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- io-channels : Channel node of a voltage io-channel.
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- shunt-resistor-micro-ohms : The shunt resistance in microohms.
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Example:
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The system current is measured by measuring the voltage over a
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3.3 ohms shunt resistor.
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sysi {
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compatible = "current-sense-shunt";
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io-channels = <&tiadc 0>;
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/* Divide the voltage by 3300000/1000000 (or 3.3) for the current. */
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shunt-resistor-micro-ohms = <3300000>;
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};
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&i2c {
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tiadc: adc@48 {
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compatible = "ti,ads1015";
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reg = <0x48>;
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#io-channel-cells = <1>;
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#address-cells = <1>;
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#size-cells = <0>;
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channel@0 { /* IN0,IN1 differential */
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reg = <0>;
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ti,gain = <1>;
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ti,datarate = <4>;
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};
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};
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};
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