Calibration commands, Iout_cal_gain, Iout_cal_offset – Maxim Integrated MAX15303 PMBus Command Set User Manual
Page 33: Ext_temp_cal
MAX15303 PMBus Command Set User’s Guide
Page 33 of 52
Calibration Commands
IOUT_CAL_GAIN
Reference:
Standard Command
Lockable:
Yes
Command Code:
0x38
Format:
Linear
Data Bytes:
2
Units:
mΩ
Transfer:
Read/Write Word
Factory Value:
0xB200 (0.5mΩ)
Description/Notes: See Section 14.8 of the PMBus Specification Part II.
The differential voltage measured between the DCRP and DCRN pins is divided by the value of
IOUT_CAL_GAIN and the value of
is subtracted to provide a load current signal,
accessible through the READ_IOUT command.
The factory value of 0xB200 (0.5mΩ) will be overridden during initialization by the hardware (pin-
strap) value determined by the resistances to ground detected at the ADDR1 pin, unless a specific
value of IOUT_CAL_GAIN has been written to the User Store. The value of the ADDR1 pin resistance is
measured only once during initialization (power-up).
The value of IOUT_CAL_GAIN is internally temperature compensated according to
and
Wait at least 500μs for execution after sending the IOUT_CAL_GAIN command before sending
additional PMBus commands.
IOUT_CAL_OFFSET
Reference:
Standard Command
Lockable:
Yes
Command Code:
0x39
Format:
Linear
Data Bytes:
2
Units:
A
Transfer:
Read/Write Word
Factory Value:
0x0000 (0A)
Description/Notes: See Section 14.9 of the PMBus Specification Part II.
The differential voltage measured between the DCRP and DCRN pins is divided by the value of
and the value of IOUT_CAL_OFFSET is subtracted to provide a load current signal,
accessible through the READ_IOUT command.
Note that the MAX15303 implementation of IOUT_CAL_OFFSET differs from the PMBus specification
because the sign of IOUT_CAL_OFFSET is inverted (i.e., IOUT_CAL_OFFSET is subtracted rather than
added.)
EXT_TEMP_CAL
Reference:
Maxim Specific
Lockable:
Yes
Command Code:
0xF8
Format:
Linear
Data Bytes:
6 (see Description)
Units:
Scalar, °K, 1/°C
Transfer:
Read/Write Block
Factory Value:
0.004, -8°K, 0.0038/°C
Description/Notes: The EXT_TEMP_CAL command allows calibration of the external temperature sense signal and
adjustment of the current-sense element temperature coefficient. The three arguments of the