ina3221.rst (3171B)
1Kernel driver ina3221 2===================== 3 4Supported chips: 5 6 * Texas Instruments INA3221 7 8 Prefix: 'ina3221' 9 10 Addresses: I2C 0x40 - 0x43 11 12 Datasheet: Publicly available at the Texas Instruments website 13 14 https://www.ti.com/ 15 16Author: Andrew F. Davis <afd@ti.com> 17 18Description 19----------- 20 21The Texas Instruments INA3221 monitors voltage, current, and power on the high 22side of up to three D.C. power supplies. The INA3221 monitors both shunt drop 23and supply voltage, with programmable conversion times and averaging, current 24and power are calculated host-side from these. 25 26Sysfs entries 27------------- 28 29======================= ======================================================= 30in[123]_label Voltage channel labels 31in[123]_enable Voltage channel enable controls 32in[123]_input Bus voltage(mV) channels 33curr[123]_input Current(mA) measurement channels 34shunt[123]_resistor Shunt resistance(uOhm) channels 35curr[123]_crit Critical alert current(mA) setting, activates the 36 corresponding alarm when the respective current 37 is above this value 38curr[123]_crit_alarm Critical alert current limit exceeded 39curr[123]_max Warning alert current(mA) setting, activates the 40 corresponding alarm when the respective current 41 average is above this value. 42curr[123]_max_alarm Warning alert current limit exceeded 43in[456]_input Shunt voltage(uV) for channels 1, 2, and 3 respectively 44in7_input Sum of shunt voltage(uV) channels 45in7_label Channel label for sum of shunt voltage 46curr4_input Sum of current(mA) measurement channels, 47 (only available when all channels use the same resistor 48 value for their shunt resistors) 49curr4_crit Critical alert current(mA) setting for sum of current 50 measurements, activates the corresponding alarm 51 when the respective current is above this value 52 (only effective when all channels use the same resistor 53 value for their shunt resistors) 54curr4_crit_alarm Critical alert current limit exceeded for sum of 55 current measurements. 56samples Number of samples using in the averaging mode. 57 58 Supports the list of number of samples: 59 60 1, 4, 16, 64, 128, 256, 512, 1024 61 62update_interval Data conversion time in millisecond, following: 63 64 update_interval = C x S x (BC + SC) 65 66 * C: number of enabled channels 67 * S: number of samples 68 * BC: bus-voltage conversion time in millisecond 69 * SC: shunt-voltage conversion time in millisecond 70 71 Affects both Bus- and Shunt-voltage conversion time. 72 Note that setting update_interval to 0ms sets both BC 73 and SC to 140 us (minimum conversion time). 74======================= =======================================================