Datasheet

LTC3880/LTC3880-1
69
3880fc
For more information www.linear.com/LTC3880
PMBus COMMAND DETAILS
BIT MEANING
7 Reserved, set to 0.
6 If V
OUT0
RANGE = 1, the maximum output voltage
for V0 is 2.75V. If RANGE = 0, the maximum output
voltage for V0 is 4.096V.
5 If V
OUT1
RANGE = 1, the maximum output voltage
for V1 is 2.75V. If RANGE = 0, the maximum output
voltage for V1 is 5.5V.
4 Share Clock Enable : If this bit is 1, the
SHARE_CLK pin will not be released until
V
IN
> VIN_ON. The SHARE_CLK pin will be
pulled low when V
IN
< VIN_OFF. If this bit is 0, the
SHARE_CLK pin will not be pulled low when VIN <
VIN_OFF except for the initial application of VIN.
3 Reserved
BIT [2:0] CHANNEL 0 (DEGREES) CHANNEL 1 (DEGREES)
000b 0 180
001b 90 270
010b 0 240
011b 0 120
100b 120 240
101b 60 240
110b 120 300
This command has one data byte.
FREQUENCY_SWITCH
The FREQUENCY_SWITCH command sets the switching frequency, in kHz, of a PMBus device.
Supported Frequencies:
VALUE [15:0] RESULTING FREQUENCY (TYP)
0x0000 External Oscillator
0xF3E8 250kHz
0xFABC 350kHz
0xFB52 425kHz
0xFBE8 500kHz
0x023F 575kHz
0x028A 650kHz
0x02EE 750kHz
0x03E8 1000kHz
The part must be in the OFF state to process this command. Either the RUN pins must be low or the part must be
commanded off. If the part is in the RUN state and this command is written, the command will be ignored and a BUSY
fault will be asserted. When the part is commanded off and the frequency is changed, a PLL_UNLOCK status may be
detected as the PLL locks onto the new frequency.
This command has two data bytes and is formatted in Linear_5s_11s format.