LTC3883 Datasheet, PDF (76/112 Pages) Linear Technology – Single Phase Step-Down DC/DC Controller with Digital Power System Management

LTC3883/LTC3883-1
PMBus Command Details
If the external temperature sense network fails to detect a READ_TEMPERATURE_1 reading of –50°C to 150°C, the
variable T_S in the self-heating algorithm will be set to a fixed value of –50°C. See READ_TEMPERATURE_1 for more
information.
MFR_T_SELF_HEAT is a read-only command that has two data bytes and is formatted in Linear_5_11s format.
MFR_IOUT_CAL_GAIN_TAU_INV has two data bytes and is formatted in Linear_5_11 format.
MFR_IOUT_CAL_GAIN_THETA has two data bytes and is formatted in Linear_5_11 format.
MFR_T_SELF_HEAT Data Content
Bit(s) Symbol
b[15:0] Mfr_t_self_heat
Operation
Values are limited to the range 0°C to 50°C.
MFR_IOUT_CAL_GAIN_THETA Data Content
Bit(s) Symbol
Operation
b[15:0] Mfr_iout_cal_gain_theta
Values ≤ 0 set MFR_T_SELF_HEAT to zero.
MFR_IOUT_CAL_GAIN_TAU_INV Data Content
Bit(s) Symbol
Operation
b[15:0] Mfr_iout_cal_gain_tau_inv Values ≤ 0 set MFR_T_SELF_HEAT to zero.
Values ≥ 1 set MFR_T_SELF_HEAT to MFR_IOUT_CAL_GAIN_THETA • READ_IOUT • (V_ISENSEP – V_ISENSEM).
Output Current
COMMAND NAME
IOUT_OC_FAULT_LIMIT
IOUT_OC_WARN_LIMIT
CMD CODE DESCRIPTION
0x46 Output overcurrent fault limit.
0x4A Output overcurrent warning limit.
TYPE
R/W Word
DATA
FORMAT
L11
R/W Word
L11
UNITS
A
A
DEFAULT
NVM
VALUE
Y
29.75
0xDBB8
Y
20.0
0xDA80
IOUT_OC_FAULT_LIMIT
The IOUT_OC_FAULT_LIMIT command sets the value of the peak output current limit, in amperes. When the controller
is in current limit, the overcurrent detector will indicate an overcurrent fault condition. The programmed overcurrent
fault limit value is rounded up to the nearest one of the following set of discrete values:
25mV/IOUT_CAL_GAIN
28.6mV/IOUT_CAL_GAIN
32.1mV/IOUT_CAL_GAIN
35.7mV/IOUT_CAL_GAIN
39.3mV/IOUT_CAL_GAIN
42.9mV/IOUT_CAL_GAIN
46.4mV/IOUT_CAL_GAIN
50mV/IOUT_CAL_GAIN
Low Range (1.5x Nominal Loop Gain)
MFR_PWM_MODE_LTC3883 [7]=0
3883f
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