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.