Техническая Спецификация для Linear Technology LTM4619EV Demo Board µModule Regulator with Tracking DC1453A DC1453A

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LTM4619
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4619fb
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operaTion
The LTM4619 is a dual-output standalone non-isolated 
switching mode DC/DC power supply. It can deliver up to 
4A (DC current) for each output with few external input and 
output capacitors. This module provides precisely regulated 
output voltages programmable via external resistors from 
0.8VDC to 5.0VDC over 4.5V to 26.5V input voltages. The 
typical application schematic is shown in Figure 18.
The LTM4619 has integrated constant frequency current 
mode regulators and built-in power MOSFET devices with 
fast switching speed. The typical switching frequency is 
780kHz. To reduce switching noise, the two outputs are 
interleaved with 180° phase internally and can be synchro-
nized externally using the MODE/PLLIN pin.
With current mode control and internal feedback loop 
compensation, the LTM4619 module has sufficient stabil-
ity margins and good transient performance with a wide 
range of output capacitors, even with all ceramic output 
capacitors.
Current mode control provides cycle-by-cycle fast current 
limit and current foldback in a short-circuit condition. 
Internal overvoltage and undervoltage comparators pull 
the open-drain PGOOD output low if the output feedback 
voltage exits a ±7.5% window around the regulation point. 
The power good pin is disabled during start-up.
Pulling the RUN pin below 1.2V forces the controller into 
its shutdown state, by turning off both MOSFETs. The  
TK/SS pin is used for programming the output voltage 
ramp and voltage tracking during start-up. See the Ap-
plications Information section.
The LTM4619 is internally compensated to be stable over 
all operating conditions. LTpowerCAD™ is available for 
transient and stability analysis. The V
FB
 pin is used to 
program the output voltage with a single external resistor 
to ground. Multiphase operation can be easily employed 
with the synchronization. 
High efficiency at light loads can be accomplished with 
selectable Burst Mode operation or pulse-skipping mode 
using the MODE/PLLIN pin. Efficiency graphs are provided 
for light load operations in the Typical Performance Char-
acteristics section.