LTM4686BEVPBF datasheet(117/130 Pages) AD

117 / 130 page

LTM4686B

117

Rev. 0

For more information www.analog.com

APPENDIX C: PMBUS COMMAND DETAILS

READ_VIN

The READ_VIN command returns the measured SVIN input voltage, in volts.

This read-only command has two data bytes and is formatted in Linear_5s_11s format.

READ_VOUT

The READ_VOUT command returns the measured output voltage in the same format as set by the VOUT_MODE

command.

This read-only command has two data bytes and is formatted in Linear_16u format.

READ_IIN

The READ_IIN command returns the input current in Amperes. Note: Input current is calculated from READ_IOUT

current and the READ_DUTY_CYCLE value from both outputs plus the MFR_IIN_OFFSET. For accurate values at low

currents the part must be in continuous conduction mode. The greatest source of error if DCR sensing is used, is the

accuracy of the inductor parasitic DC resistance (DCR) at room temperature IOUT_CAL_GAIN.

READ_IIN = MFR_READ_IIN_PAGE0 + MFR_READ_IIN_PAGE1

This read-only command has two data bytes and is formatted in Linear_5s_11s format.

MFR_READ_IIN

The MFR_READ_IIN command is a paged reading of the input current that applies the paged MFR_IIN_OFFSET

parameter. This calculation is similar to READ_IIN except the paged values are used.

MFR_READ_IIN = MFR_IIN_OFFSET + (IOUT • DUTY_CYCLE)

This command has 2 data bytes and is formatted in Linear_5s_11s format.

READ_IOUT

The READ_IOUT command returns the average output current in amperes. The IOUT value is a function of:

a) the differential voltage derived from the power inductor ∆ISNSn

b) the IOUT_CAL_GAIN value

c) the MFR_IOUT_CAL_GAIN_TC value, and

d) READ_TEMPERATURE_1 value

e) The MFR_TEMP_1_GAIN and the MFR_TEMP_1_OFFSET

This read-only command has two data bytes and is formatted in Linear_5s_11s format.

READ_TEMPERATURE_1

The READ_TEMPERATURE_1 command returns the temperature, in degrees Celsius, of the external sense element.

This read-only command has two data bytes and is formatted in Linear_5s_11s format.

LTM4686BEVPBF Datasheet(PDF) 117 Page - Analog Devices