LTC3882_15 Datasheet, PDF (71/104 Pages) Linear Technology – Dual Output PolyPhase Step-Down DC/DC Voltage Mode Controller with Digital Power System Management

LTC3882
PMBus COMMAND DETAILS (PWM Configuration)
PWM CONFIGURATION
COMMAND NAME
FREQUENCY_SWITCH
CMD
CODE DESCRIPTION
0x33 PWM frequency control.
MFR_PWM_CONFIG_LTC3882
0xF5 LTC3882 PWM configuration common to
both channels.
MFR_CHAN_CONFIG_LTC3882
0xD0 LTC3882 channel-specific configuration.
MFR_PWM_MODE_LTC3882
0xD4 LTC3882 channel-specific PWM mode
control.
Related commands MFR_TEMP_1_GAIN_ADJUST, MFR_TEMP_1_OFFSET.
DATA
TYPE PAGED FORMAT
R/W Word N
L11
R/W Byte N
Reg
UNITS NVM
kHz l
l
DEFAULT
VALUE
500kHz
0xFBE8
0x14
R/W Byte Y
Reg
R/W Byte Y
Reg
l
0x1D
l
0x48
FREQUENCY_SWITCH
The FREQUENCY_SWITCH command sets the switching frequency of both LTC3882 PWM channels in kilohertz. At
most only one IC sharing SYNC should be programmed as clock master. See bit 4 in MFR_CONFIG_ALL_LTC3882.
FREQUENCY_SWITCH value will determine the free-running frequency of PWM operation if an expected external clock
source is not present or the bussed SYNC line becomes stuck due an external fault or conflict. Both PWM channels
must be turned off by the RUNn pins, OPERATION command, or their combination, to process this command. If this
command is sent while either PWM controller is operating, the LTC3882 will NACK the command byte, ignore the
command and its data, and assert a BUSY fault. A PLL Unlocked status may be reported after changing the value of
this command until the new frequency is established.
Supported Frequencies:
VALUE
0x0A71
0x03E8
0x0384
0x02EE
0x0258
0xFBE8
0xFB84
0xFB20
0xFABC
0XFA58
0xF3E8
0x0000
PWM FREQUENCY (TYPICAL)
1.25MHz
1MHz
900kHz
750kHz
600kHz
500kHz
450kHz
400kHz
350kHz
300kHz
250kHz
External SYNC Only
This command has two data bytes in Linear_5s_11s format.
For more information www.linear.com/LTC3882
3882f
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