LTC3883 Datasheet, PDF (68/112 Pages) Linear Technology – Single Phase Step-Down DC/DC Controller with Digital Power System Management

LTC3883/LTC3883-1
PMBus Command Details
MFR_RESET
This command provides a means by which the user can perform a reset of the LTC3883.
This write-only command has no data bytes.
PWM Configuration
COMMAND NAME
MFR_PWM_MODE_
LTC3883
MFR_PWM_CONFIG_
LTC3883
FREQUENCY_SWITCH
CMD CODE DESCRIPTION
0xD4 Configuration for the PWM engine.
0xF5 Set numerous parameters for the DC/DC controller including
phasing.
0x33 Switching frequency of the controller.
DATA
DEFAULT
TYPE FORMAT UNITS NVM VALUE
R/W Byte Reg
Y 0xD2
R/W Byte Reg
Y 0x10
R/W Word L11
kHz Y 350
0xFABC
MFR_PWM_MODE_LTC3883
The MFR_PWM_MODE_LTC3883 command allows the user to program the PWM controller to use Burst Mode operation,
discontinuous (pulse-skipping mode), or forced continuous conduction mode.
BIT
7
0b
1b
6
[5:4]
00b
01b
10b
3
2
Bit[1:0]
00b
01b
10b
MEANING
Use High Range of I_LIMIT
Low Current Range
High Current Range
Enable Servo Mode
READ_IIN Gain Setting
2x Gain, 50mV Max Input
4x Gain, 20mV Max Input
8x, Gain, 8mV Max Input
Start DCR Auto Calibration
Reserved
Mode
Discontinuous
Burst Mode Operation
Forced Continuous
Whenever the channel is ramping on, the PWM mode will be discontinuous, regardless of the value of this
command.
Bit [7] of this command determines if the part is in high range or low range of the IOUT_OC_FAULT_LIMIT command.
Changing this bit value changes the PWM loop gain and compensation. Changing this bit value whenever an output is
active may have detrimental system results.
Bit [6] The LTC3883 will not servo while the part is OFF, ramping on or ramping off. When set to a one, the output servo
is enabled. The output set point DAC will be slowly adjusted to minimize the difference between the READ_VOUT_ADC
and the VOUT_COMMAND (or the appropriate margined value).
Bit[5:4] set the READ_IIN gain and range setting of the input current sense amplifier.
3883f
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