LTC3882-1
74
Rev A
For more information
FREQUENCY_SWITCH
The FREQUENCY_SWITCH command sets the switching frequency of both LTC3882-1 PWM channels in kilohertz. At
most only one IC sharing SYNC should be programmed as clock master. See bit 4 in MFR_CONFIG_ALL_LTC3882-1.
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 RUN
n
pins, OPERATION command, or their combination, to process this command. If this
command is sent while either PWM controller is operating, the LTC3882-1 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
PWM FREQUENCY (TYPICAL)
0x0A71
1.25MHz
0x03E8
1MHz
0x0384
900kHz
0x02EE
750kHz
0x0258
600kHz
0xFBE8
500kHz
0xFB84
450kHz
0xFB20
400kHz
0xFABC
350kHz
0XFA58
300kHz
0xF3E8
250kHz
0x0000
External SYNC Only
This command has two data bytes in Linear_5s_11s format.
PWM CONFIGURATION
COMMAND NAME
CMD
CODE DESCRIPTION
TYPE
PAGED
DATA
FORMAT UNITS NVM
DEFAULT
VALUE
FREQUENCY_SWITCH
0x33 PWM frequency control.
R/W Word
N
L11
kHz
l
500kHz
0xFBE8
MFR_PWM_CONFIG_LTC3882-1
0xF5 LTC3882-1 PWM configuration common to
both channels.
R/W Byte
N
Reg
l
0x14
MFR_CHAN_CONFIG_LTC3882-1
0xD0 LTC3882-1 channel-specific configuration.
R/W Byte
Y
Reg
l
0x1D
MFR_PWM_MODE_LTC3882-1
0xD4 LTC3882-1 channel-specific PWM mode
control.
R/W Byte
Y
Reg
l
0xC8
Related commands MFR_TEMP_1_GAIN_ADJUST, MFR_TEMP_1_OFFSET.
PMBus COMMAND DETAILS
(PWM Configuration)