LTC3414
4A, 4MHz, Monolithic
Synchronous Step-Down Regulator
FEATURES
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DESCRIPTIO
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High Efficiency: Up to 95%
4A Output Current
Low Quiescent Current: 64µA
Low R
DS(ON)
Internal Switch: 67mΩ
Programmable Frequency: 300KHz to 4MHz
2.25V to 5.5V Input Voltage Range
±2%
Output Voltage Accuracy
0.8V Reference Allows Low Output Voltage
Selectable Forced Continuous/Burst Mode
®
operation
with Adjustable Burst Clamp
Synchronizable Switching Frequency
Low Dropout Operation: 100% Duty Cycle
Power Good Output Voltage Monitor
Overtemperature Protected
Available in 20-Lead Exposed TSSOP Package
The LTC
®
3414 is a high efficiency monolithic synchro-
nous, step-down DC/DC converter utilizing a constant
frequency, current mode architecture. It operates from an
input voltage range of 2.25V to 5.5V and provides a
regulated output voltage from 0.8V to 5V while delivering
up to 4A of output current. The internal synchronous
power switch with 67mΩ on-resistance increases effi-
ciency and eliminates the need for an external Schottky
diode. Switching frequency is set by an external resistor or
can be synchronized to an external clock. 100% duty cycle
provides low dropout operation extending battery life in
portable systems. OPTI-LOOP
®
compensation allows the
transient response to be optimized over a wide range of
loads and output capacitors.
The LTC3414 can be configured for either Burst Mode
operation or forced continuous operation. Forced continu-
ous operation reduces noise and RF interference while
Burst Mode operation provides high efficiency by reduc-
ing gate charge losses at light loads. In Burst Mode
operation, external control of the burst clamp level allows
the output voltage ripple to be adjusted according to the
requirements of the application.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation.
APPLICATIO S
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Point-of-Load Regulation
Notebook Computers
Portable Instruments
Distributed Power Systems
TYPICAL APPLICATIO
V
IN
2.7V TO 5.5V
PV
IN
SV
IN
2.2M
294k
RT
22µF
100
95
PGOOD
LTC3414
SW
RUN/SS
PGND
SGND
V
FB
C
OUT
*
0.47µH
V
OUT
2.5V AT 4A
90
LTC3414 Efficiency Curve
Burst Mode OPERATION
EFFICIENCY (%)
85
80
75
70
65
60
FORCED
CONTINUOUS
1000pF
R
ITH
*
470pF
I
TH
SYNC/MODE
110k
75k
392k
3414 F01a
55
50
0.001
0.01
0.1
1.0
LOAD CURRENT (A)
10
3414 F01b
*BURST MODE OPERATION: C
OUT
= 470µF SANYO POSCAP 4TPB470M, R
ITH
= 20k
FORCED CONTINUOUS: C
OUT
= (2) 100µF TDKC4532X5ROJ107M, R
ITH
= 12.1k
Figure 1. 2.5V/4A Step-Down Regulator
3414f
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