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Kernel driver ltc2990
=====================
Supported chips:
* Linear Technology LTC2990
Prefix: 'ltc2990'
Addresses scanned: -
Datasheet: http://www.linear.com/product/ltc2990
Author:
- Mike Looijmans <mike.looijmans@topic.nl>
- Tom Levens <tom.levens@cern.ch>
Description
-----------
LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor.
The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4)
can be combined to measure a differential voltage, which is typically used to
measure current through a series resistor, or a temperature with an external
diode.
Usage Notes
-----------
This driver does not probe for PMBus devices. You will have to instantiate
devices explicitly.
Sysfs attributes
----------------
============= ==================================================
in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V)
temp1_input Internal chip temperature in millidegrees Celsius
============= ==================================================
A subset of the following attributes are visible, depending on the measurement
mode of the chip.
============= ==========================================================
in[1-4]_input Voltage at V[1-4] pin in millivolt
temp2_input External temperature sensor TR1 in millidegrees Celsius
temp3_input External temperature sensor TR2 in millidegrees Celsius
curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor
curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor
============= ==========================================================
The "curr*_input" measurements actually report the voltage drop across the
input pins in microvolts. This is equivalent to the current through a 1mOhm
sense resistor. Divide the reported value by the actual sense resistor value
in mOhm to get the actual value.