ina3221.rst 3.1 KB
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Kernel driver ina3221
Supported chips:


Texas Instruments INA3221
Prefix: 'ina3221'
Addresses: I2C 0x40 - 0x43
Datasheet: Publicly available at the Texas Instruments website

http://www.ti.com/


Author: Andrew F. Davis <afd@ti.com>
Description
The Texas Instruments INA3221 monitors voltage, current, and power on the high
side of up to three D.C. power supplies. The INA3221 monitors both shunt drop
and supply voltage, with programmable conversion times and averaging, current
and power are calculated host-side from these.
Sysfs entries


in[123]_label
Voltage channel labels

in[123]_enable
Voltage channel enable controls

in[123]_input
Bus voltage(mV) channels

curr[123]_input
Current(mA) measurement channels

shunt[123]_resistor
Shunt resistance(uOhm) channels

curr[123]_crit
Critical alert current(mA) setting, activates the
corresponding alarm when the respective current
is above this value

curr[123]_crit_alarm
Critical alert current limit exceeded

curr[123]_max
Warning alert current(mA) setting, activates the
corresponding alarm when the respective current
average is above this value.

curr[123]_max_alarm
Warning alert current limit exceeded

in[456]_input
Shunt voltage(uV) for channels 1, 2, and 3 respectively

in7_input
Sum of shunt voltage(uV) channels

in7_label
Channel label for sum of shunt voltage

curr4_input
Sum of current(mA) measurement channels,
(only available when all channels use the same resistor
value for their shunt resistors)

curr4_crit
Critical alert current(mA) setting for sum of current
measurements, activates the corresponding alarm
when the respective current is above this value
(only effective when all channels use the same resistor
value for their shunt resistors)

curr4_crit_alarm
Critical alert current limit exceeded for sum of
current measurements.

samples
Number of samples using in the averaging mode.
Supports the list of number of samples:

1, 4, 16, 64, 128, 256, 512, 1024


update_interval
Data conversion time in millisecond, following:

update_interval = C x S x (BC + SC)

C:  number of enabled channels
S:  number of samples
BC: bus-voltage conversion time in millisecond
SC: shunt-voltage conversion time in millisecond


Affects both Bus- and Shunt-voltage conversion time.
Note that setting update_interval to 0ms sets both BC
and SC to 140 us (minimum conversion time).
in[123]_label	Voltage channel labels
in[123]_enable	Voltage channel enable controls
in[123]_input	Bus voltage(mV) channels
curr[123]_input	Current(mA) measurement channels
shunt[123]_resistor	Shunt resistance(uOhm) channels
curr[123]_crit	Critical alert current(mA) setting, activates the corresponding alarm when the respective current is above this value
curr[123]_crit_alarm	Critical alert current limit exceeded
curr[123]_max	Warning alert current(mA) setting, activates the corresponding alarm when the respective current average is above this value.
curr[123]_max_alarm	Warning alert current limit exceeded
in[456]_input	Shunt voltage(uV) for channels 1, 2, and 3 respectively
in7_input	Sum of shunt voltage(uV) channels
in7_label	Channel label for sum of shunt voltage
curr4_input	Sum of current(mA) measurement channels, (only available when all channels use the same resistor value for their shunt resistors)
curr4_crit	Critical alert current(mA) setting for sum of current measurements, activates the corresponding alarm when the respective current is above this value (only effective when all channels use the same resistor value for their shunt resistors)
curr4_crit_alarm	Critical alert current limit exceeded for sum of current measurements.
samples	Number of samples using in the averaging mode. Supports the list of number of samples: 1, 4, 16, 64, 128, 256, 512, 1024
update_interval	Data conversion time in millisecond, following: update_interval = C x S x (BC + SC) C: number of enabled channels S: number of samples BC: bus-voltage conversion time in millisecond SC: shunt-voltage conversion time in millisecond Affects both Bus- and Shunt-voltage conversion time. Note that setting update_interval to 0ms sets both BC and SC to 140 us (minimum conversion time).