Datasheet

LTC3883/LTC3883-1
70
3883fa
For more information www.linear.com/LTC3883
PMBus COMMAND DETAILS
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. The RUN pin 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.
VOLTAGE
Input Voltage and Limits
COMMAND NAME CMD CODE DESCRIPTION TYPE DATA FORMAT UNITS NVM DEFAULT VALUE
VIN_OV_FAULT_ LIMIT 0x55 Input supply overvoltage fault limit. R/W
Word
L11 V Y 15.5
0xD3E0
VIN_UV_WARN_LIMIT
0x58 Input supply undervoltage warning limit. R/W
Word
L11 V Y 6.3
0xCB26
VIN_ON 0x35
Input voltage at which the unit should start
power conversion.
R/W
Word
L11 V Y 6.5
0xCB40
VIN_OFF 0x36
Input voltage at which the unit should stop
power conversion.
R/W
Word
L11 V Y 6.0
0xCB00
MFR_R
VIN 0xF7 The resistance value of the V
IN
pin filter
element in milliohms
R/W
Word
L11 mΩ Y 3000
0x12EE
VIN_OV_FAULT_LIMIT
The VIN_OV_FAULT_LIMIT command sets the value of the measured input voltage, in volts, that causes an input
overvoltage fault. The fault is detected with the A/D converter resulting in latency up to 120ms.
This command has two data bytes and is formatted in Linear_5s_11s format.
VIN_UV_WARN_LIMIT
The VIN_UV_WARN_LIMIT command sets the value of the input voltage that causes an input undervoltage warning.
The warning is detected with the A/D converter resulting in latency up to 120ms.
This command
has two data bytes and is formatted in Linear_5s_11s format.