79 lines
2.4 KiB
Plaintext
79 lines
2.4 KiB
Plaintext
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Analog Devices AD5758 DAC device driver
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Required properties for the AD5758:
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- compatible: Must be "adi,ad5758"
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- reg: SPI chip select number for the device
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- spi-max-frequency: Max SPI frequency to use (< 50000000)
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- spi-cpha: is the only mode that is supported
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Required properties:
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- adi,dc-dc-mode: Mode of operation of the dc-to-dc converter
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Dynamic Power Control (DPC)
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In this mode, the AD5758 circuitry senses the output
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voltage and dynamically regulates the supply voltage,
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VDPC+, to meet compliance requirements plus an optimized
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headroom voltage for the output buffer.
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Programmable Power Control (PPC)
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In this mode, the VDPC+ voltage is user-programmable to
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a fixed level that needs to accommodate the maximum output
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load required.
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The output of the DAC core is either converted to a
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current or voltage output at the VIOUT pin. Only one mode
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can be enabled at any one time.
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The following values are currently supported:
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* 1: DPC current mode
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* 2: DPC voltage mode
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* 3: PPC current mode
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Depending on the selected output mode (voltage or current) one of the
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two properties must
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be present:
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- adi,range-microvolt: Voltage output range
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The array of voltage output ranges must contain two fields:
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* <0 5000000>: 0 V to 5 V voltage range
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* <0 10000000>: 0 V to 10 V voltage range
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* <(-5000000) 5000000>: ±5 V voltage range
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* <(-10000000) 10000000>: ±10 V voltage range
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- adi,range-microamp: Current output range
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The array of current output ranges must contain two fields:
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* <0 20000>: 0 mA to 20 mA current range
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* <0 24000>: 0 mA to 24 mA current range
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* <4 24000>: 4 mA to 20 mA current range
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* <(-20000) 20000>: ±20 mA current range
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* <(-24000) 24000>: ±24 mA current range
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* <(-1000) 22000>: −1 mA to +22 mA current range
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Optional properties:
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- adi,dc-dc-ilim-microamp: The dc-to-dc converter current limit
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The following values are currently supported [uA]:
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* 150000
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* 200000
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* 250000
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* 300000
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* 350000
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* 400000
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- adi,slew-time-us: The time it takes for the output to reach the
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full scale [uS]
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The supported range is between 133us up to 1023984375us
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AD5758 Example:
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dac@0 {
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compatible = "adi,ad5758";
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reg = <0>;
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spi-max-frequency = <1000000>;
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spi-cpha;
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adi,dc-dc-mode = <2>;
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adi,range-microvolt = <0 10000000>;
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adi,dc-dc-ilim-microamp = <200000>;
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adi,slew-time-us = <125000>;
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};
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