ina3221.rst 3.1 KB

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