ltm4601hv Linear Technology Corporation, ltm4601hv Datasheet - Page 9

• Manufacturer Part Number: ltm4601hv
• Description: 12a 28vin Dc/dc ?module With Pll, Output Tracking And Margining
• Manufacturer: Linear Technology Corporation

OPERATIO
Power Module Description
The LTM4601HV is a standalone nonisolated switching
mode DC/DC power supply. It can deliver up to 12A of
DC output current with some external input and output
capacitors. This module provides precisely regulated
output voltage programmable via one external resistor
from 0.6V
voltage. The typical application schematics are shown in
Figures 19 and 20.
The LTM4601HV has an integrated constant on-time
current mode regulator, ultralow R
switching speed and integrated Schottky diodes. The typical
switching frequency is 850kHz at full load. With current
mode control and internal feedback loop compensation,
the LTM4601HV module has suffi cient stability margins
and good transient performance under a wide range of
operating conditions and with a wide range of output
capacitors, even all ceramic output capacitors.
Current mode control provides cycle-by-cycle fast current
limit. Besides, foldback current limiting is provided in an
overcurrent condition while V
and undervoltage comparators pull the open-drain PGOOD
output low if the output feedback voltage exits a ±10%
window around the regulation point. Furthermore, in an
DECOUPLI G REQUIRE E TS
SYMBOL
C
C
IN
OUT
DC
to 5.0V
PARAMETER
External Input Capacitor Requirement
(V
External Output Capacitor Requirement
(V
U
U
IN
IN
= 4.5V to 28V, V
= 4.5V to 28V, V
DC
over a 4.5V to 28V wide input
FB
drops. Internal overvoltage
OUT
OUT
= 2.5V)
= 2.5V)
DS(ON)
W U
FETs with fast
CONDITIONS
I
I
OUT
OUT
T
= 12A, 3× 10µF Ceramics
= 12A
A
= 25°C, V
overvoltage condition, internal top FET Q1 is turned off
and bottom FET Q2 is turned on and held on until the
overvoltage condition clears.
Pulling the RUN pin below 1V forces the controller into its
shutdown state, turning off both Q1 and Q2. At low load
current, the module works in continuous current mode by
default to achieve minimum output voltage ripple.
When DRV
5V linear regulator powers the internal gate drivers. If a
5V external bias supply is applied on the DRV
an effi ciency improvement will occur due to the reduced
power loss in the internal linear regulator. This is especially
true at the higher input voltage range.
The LTM4601HV has a very accurate differential remote
sense amplifi er with very low offset. This provides for
very accurate remote sense voltage measurement. The
MPGM pin, MARG0 pin and MARG1 pin are used to sup-
port voltage margining, where the percentage of margin
is programmed by the MPGM pin, and the MARG0 and
MARG1 select margining.
The PLLIN pin provides frequency synchronization of the
device to an external clock. The TRACK/SS pin is used for
power supply tracking and soft-start programming.
IN
= 12V. Use Figure 1 confi guration.
CC
pin is connected to INTV
MIN
100
20
LTM4601HV
TYP
200
30
CC
an integrated
MAX
CC
pin, then
UNITS
4601hvf
9
µF
µF