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.