LTC3624_15 Datasheet, PDF (1/20 Pages) Linear Technology – 17V, 2A Synchronous Step-Down Regulator with 3.5A Quiescent Current

LTC3624/LTC3624-2
17V, 2A Synchronous
Step-Down Regulator with
3.5µA Quiescent Current
Features
n _{Wide VIN Range: 2.7V to 17V}
n _{Wide VOUT Range: 0.6V to VIN}
n _{95% Max Efficiency}
n _{Low IQ: 3.5µA, Zero-Current Shutdown}
n _{Constant Frequency (1MHz/2.25MHz)}
n _{Fixed VOUT Options Available}
n _{Low Dropout Operation (100% Duty Cycle) with}
Ultralow I_Q
n _{2A Rated Output Current}
n _{±1% Output Voltage Accuracy}
n _{Current Mode Operation for Excellent Line and Load}
Transient Response
n _{Synchronizable to External Clock}
n _{Pulse-Skipping, Forced Continuous, Burst Mode}^®
Operation
n _{Internal Compensation and Soft-Start}
n _{Overtemperature Protection}
n _{Compact 8-Lead DFN (3mm × 3mm) Package}
Applications
n _{Battery Powered Equipment}
n _{Portable Instrumentation}
n _{Emergency Radios}
n _{General Purpose Step-Down Supplies}
Description
The LTC^®3624/LTC3624-2 is a high efficiency 17V, 2A
synchronous monolithic step-down regulator. The switch-
ing frequency is fixed to 1MHz (LTC3624) or 2.25MHz
(LTC3642-2) with a ±40% synchronization range. The
regulator features ultralow quiescent current and high
efficiency over a wide V_OUT range.
The step-down regulator operates from an input voltage
range of 2.7V to 17V and provides an adjustable output
range from 0.6V to V_IN while delivering up to 2A of output
current. A user-selectable mode input is provided to allow
the user to trade off ripple noise for light load efficiency;
Burst Mode operation provides the highest efficiency at
light loads, while pulse-skipping mode provides the lowest
voltage ripple. The MODE pin can also be used to sync the
switching frequency to an external clock.
LTC3624/LTC3624-2 Options
PART NAME
FREQUENCY
LTC3624
1MHz
LTC3624-3.3
1MHz
LTC3624-5
1MHz
LTC3624-2
2.25MHz
LTC3624-23.3
2.25MHz
LTC3624-25
2.25MHz
V_OUT
Adjustable
3.3V
5V
Adjustable
3.3V
5V
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258,
6498466, 6611131, 6177787, 5705919, 5847554, 6703692.
Typical Application
5V V_OUT with 800mA Burst Clamp, f_SW = 1MHz
V_IN
5.6V TO 17V
10µF
V_IN
SW
LTC3624-5
3.3µH
RUN
FB
MODE/SYNC
INTV_CC
GND
2.2µF
V_OUT
5V
2A
47µF
36242 TA01a
Efficiency and Power Loss vs Load
100
1.2
90
80 VOUT = 5V
1.0
70 BURST MODE OPERATION
0.8
60
50
0.6
40
30
0.4
20
V_IN = 12V
V_IN = 8V
0.2
10
V_IN = 6V
FREQ = 1MHz
0
0
0
0.5
1
1.5
2
LOAD CURRENT (A)
3624 TA01b
For more information www.linear.com/LTC3624
36242fc
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