LTC3630 Datasheet, PDF (1/26 Pages) Linear Technology – High Efficiency, 65V 500mA Synchronous

LTC3630
High Efficiency, 65V
500mA Synchronous
Step-Down Converter
FEATURES
n _{Wide Operating Input Voltage Range: 4V to 65V}
n _{Synchronous Operation for Highest Efficiency}
n _{Internal High Side and Low Side Power MOSFETs}
n _{No Compensation Required}
n _{Adjustable 50mA to 500mA Maximum Output Current}
n _{Low Dropout Operation: 100% Duty Cycle}
n _{Low Quiescent Current: 12μA}
n _{Wide Output Range: 0.8V to VIN}
n _{0.8V ±1% Feedback Voltage Reference}
n _{Precise RUN Pin Threshold}
n _{Internal and External Soft-Start}
n _{Programmable 1.8V, 3.3V, 5V or Adjustable Output}
n _{Few External Components Required}
n _{Low Profile (0.75mm) 3mm × 5mm DFN and}
Thermally-Enhanced MSE16 Packages
APPLICATIONS
n _{Industrial Control Supplies}
n _{Medical Devices}
n _{Distributed Power Systems}
n _{Portable Instruments}
n _{Battery-Operated Devices}
n _Automotive
n _Avionics
DESCRIPTION
The LTC^®3630 is a high efficiency step-down DC/DC
converter with internal high side and synchronous power
switches that draws only 12μA typical DC supply current
while maintaining a regulated output voltage at no load.
The LTC3630 can supply up to 500mA load current and
features a programmable peak current limit that provides
a simple method for optimizing efficiency and for reduc-
ing output ripple and component size. The LTC3630’s
combination of Burst Mode^® operation, integrated power
switches, low quiescent current, and programmable peak
current limit provides high efficiency over a broad range
of load currents.
With its wide input range of 4V to 65V, the LTC3630 is a
robust converter suited for regulating a wide variety of
power sources. Additionally, the LTC3630 includes a precise
run threshold and soft-start feature to guarantee that the
power system start-up is well-controlled in any environ-
ment. A feedback comparator output enables multiple
LTC3630s to be paralleled in higher current applications.
The LTC3630 is available in the thermally-enhanced
3mm × 5mm DFN and the MSE16 packages.
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
TYPICAL APPLICATION
4V to 65V Input to 3.3V Output, 500mA Step-Down Converter
V_IN
4V TO 65V
2.2μF
V_IN
SW
LTC3630
RUN
V_FB
SS
V_PRG1 V_PRG2
FBO
I_SET
GND
47μH
3630 TA01a
V_OUT
3.3V
100μF _500mA
w2
Efficiency vs Load Current
100
V_OUT = 3.3V
90
V_IN = 12V
80
70
V_IN = 65V
60
50
40
30
0.1
I_SET = 220kΩ||220pF
I_SET = OPEN
1
10
100
1000
LOAD CURRENT (mA)
3630 TA01b
3630fb
1