Documentation/iio/ad7380.rst

1 .. SPDX-License-Identifier: GPL-2.0-only
23 * `AD7380-4 <https://www.analog.com/en/products/ad7380-4.html>`_
24 * `AD7381-4 <https://www.analog.com/en/products/ad7381-4.html>`_
25 * `AD7383-4 <https://www.analog.com/en/products/ad7383-4.html>`_
26 * `AD7384-4 <https://www.analog.com/en/products/ad7384-4.html>`_
27 * `AD7386-4 <https://www.analog.com/en/products/ad7386-4.html>`_
28 * `AD7387-4 <https://www.analog.com/en/products/ad7387-4.html>`_
29 * `AD7388-4 <https://www.analog.com/en/products/ad7388-4.html>`_
30 * `ADAQ4370-4 <https://www.analog.com/en/products/adaq4370-4.html>`_
31 * `ADAQ4380-4 <https://www.analog.com/en/products/adaq4380-4.html>`_
32 * `ADAQ4381-4 <https://www.analog.com/en/products/adaq4381-4.html>`_
38 SPI wiring modes
39 ----------------
41 ad738x ADCs can output data on several SDO lines (1/2/4). The driver currently
42 supports only 1 SDO line.
45 -----------------
47 ad7380-4
50 ad7380-4 supports only an external reference voltage (2.5V to 3.3V). It must be
51 declared in the device tree as ``refin-supply``.
57 derived from one of its supplies (``refin-supply``)
64 - Internal reference (2.5V)
65 - External reference (2.5V to 3.3V)
67 The source is determined by the device tree. If ``refio-supply`` is present,
71 ---------------------------------
76 available: 1 (oversampling disabled)/2/4/8/16/32.
78 When the on-chip oversampling function is enabled the performance of the ADC can
86 Since the resolution boost feature causes 16-bit chips to now have 18-bit data
92 .. code-block:: bash
97 -----
100 when configured in 1 SDO line mode. 4 channels variants, can use SDOD as an
101 alert pin when configured in 1 or 2 SDO line(s) mode, although only 1 SDO line
102 mode is currently supported by the driver (see `SPI wiring modes`_).
104 At the end of a conversion the active-low alert pin gets asserted if the
111 .. code-block:: bash
118 .. code-block:: bash
128 Channel selection and sequencer (single-end chips only)
129 -------------------------------------------------------
131 Single-ended chips of this family (ad7386/7/8(-4)) have a 2:1 multiplexer in
137 export 4 channels and ad7386-4/7-4/8-4 export 8 channels.
140 0-1 or 0-3) and inputs ``AinX1`` correspond to second half (i.e 2-3 or 4-7).
143 .. code-block::
146 	         |         +----------------------------
149 	voltage0 | AinA0 --|--->|     |      |      |
150 	         |         |    | mux |----->| ADCA |---
151 	voltage2 | AinA1 --|--->|     |      |      |
155 	voltage1 | AinB0 --|--->|     |      |      |
156 	         |         |    | mux |----->| ADCB |---
157 	voltage3 | AinB1 --|--->|     |      |      |
160 	         |         +----------------------------
169 gain is selectable from device tree using the ``adi,gain-milli`` property.
174 ----------------------
176 - 2/4 SDO lines
177 - Rolling average oversampling
178 - Power down mode
179 - CRC indication
181 SPI offload support
185 `AXI SPI Engine`_ to provide SPI offload support.
187 .. _AXI SPI Engine: http://analogdevicesinc.github.io/hdl/projects/pulsar_adc/index.html
189 When SPI offload is being used, some attributes will be different.