Commit | Line | Data |
---|---|---|
df922703 ML |
1 | Kernel driver ltc2990 |
2 | ===================== | |
3 | ||
4 | Supported chips: | |
5 | * Linear Technology LTC2990 | |
6 | Prefix: 'ltc2990' | |
7 | Addresses scanned: - | |
8 | Datasheet: http://www.linear.com/product/ltc2990 | |
9 | ||
10 | Author: Mike Looijmans <mike.looijmans@topic.nl> | |
5d9ca430 | 11 | Tom Levens <tom.levens@cern.ch> |
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12 | |
13 | ||
14 | Description | |
15 | ----------- | |
16 | ||
17 | LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor. | |
18 | The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4) | |
19 | can be combined to measure a differential voltage, which is typically used to | |
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20 | measure current through a series resistor, or a temperature with an external |
21 | diode. | |
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22 | |
23 | ||
24 | Usage Notes | |
25 | ----------- | |
26 | ||
27 | This driver does not probe for PMBus devices. You will have to instantiate | |
28 | devices explicitly. | |
29 | ||
30 | ||
31 | Sysfs attributes | |
32 | ---------------- | |
33 | ||
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34 | in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) |
35 | temp1_input Internal chip temperature in millidegrees Celcius | |
36 | ||
37 | A subset of the following attributes are visible, depending on the measurement | |
38 | mode of the chip. | |
39 | ||
40 | in[1-4]_input Voltage at V[1-4] pin in millivolt | |
41 | temp2_input External temperature sensor TR1 in millidegrees Celcius | |
42 | temp3_input External temperature sensor TR2 in millidegrees Celcius | |
43 | curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor | |
44 | curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor | |
45 | ||
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46 | The "curr*_input" measurements actually report the voltage drop across the |
47 | input pins in microvolts. This is equivalent to the current through a 1mOhm | |
48 | sense resistor. Divide the reported value by the actual sense resistor value | |
49 | in mOhm to get the actual value. |