POWER LOSS (W)
LTC3622/
LTC3622-2/LTC3622-23/5
17V, Dual 1A
Synchronous Step-Down Regulator
with Ultralow Quiescent Current
FEATURES DESCRIPTION
n
Dual Step-Down Outputs: 1A Per Channel The LTC 3622 is a dual 1A output, high efficiency synchro-
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Wide V Range: 2.7V to 17V nous monolithic step-down regulator capable of operating
IN
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Wide V Range: 0.6V to V from input supplies up to 17V. The switching frequency is
OUT IN
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Up to 95% Efficiency fixed to 1MHz or 2.25MHz with a 50% synchronization
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No-Load I = 5A with Both Channels Enabled; range to an external clock. The regulator features ultralow
Q
I < 4A with Only One Channel Enabled quiescent current and high efficiency over a wide output
Q
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High Efficiency, Low Dropout Operation voltage range.
(100% Duty Cycle)
The step-down regulators operate from an input voltage
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Constant Frequency (1MHz/2.25MHz) with External
range of 2.7V to 17V and provide an adjustable output
Frequency Synchronization
from 0.6V to V while delivering up to 1A of output cur-
IN
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1% Output Voltage Accuracy
rent. A user-selectable mode input is provided to allow
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Current Mode Operation for Excellent Line and Load
the user to trade off ripple noise for light load efficiency.
Transient Response
Burst Mode operation provides the highest efficiency at
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Phase Shift Programmable with External Clock
light loads, while pulse-skipping mode provides the lowest
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Selectable Current Limit
ripple noise. The switching regulators can be synchronized
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Internal Compensation and Soft-Start
to an external clock. Furthermore, fixed V options are
OUT
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Compact 14-Pin DFN (3mm 4mm) and 16-Lead
available to eliminate the external feedback resistors.
MSOP Packages
List of LTC3622 Options
PART NAME FREQUENCY V
OUT
APPLICATIONS
LTC3622 1.00MHz Adjustable
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Battery Powered Systems
LTC3622-2 2.25MHz Adjustable
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Point-of-Load Supplies
LTC3622-23/5 2.25MHZ 5V/3.3V
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Portable Handheld Scanners
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. Patents, including 5481178, 6580258, 6498466, 6611131, 5705919.
TYPICAL APPLICATION
Efficiency vs Load Current
2.5V/5V V Application, f = 1MHz
OUT SW
100 0.6
90
V
IN
V
INTV
IN1 CC
5.5V TO 17V 0.5
80
V
IN2 MODE/SYNC
C C1
IN
70
RUN1
0.4
10F 1F
RUN2 PHASE
60
I
LIM
50 0.3
LTC3622
40
V 4.7H 6.8H V 0.2
V = 2.5V
OUT1 OUT2
OUT1
30
2.5V SW1 SW2 5V V = 5V
OUT2
1A 1A
20
V = 12V
IN
0.1
22pF 619k 619k 22pF
f = 1MHz
SW
C C 10
OUT1 OUT2
FB1 FB2
Burst Mode OPERATION
22F 22F
GND
0 0
196k 84.5k
0.0001 0.001 0.01 0.1 1
LOAD CURRENT (A)
3622 TA01b
3622 TA01
Rev D
1
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EFFICIENCY (%)LTC3622/
LTC3622-2/LTC3622-23/5
TABLE OF CONTENTS
Features ............................................................................................................................ 1
Applications ....................................................................................................................... 1
Typical Application ............................................................................................................... 1
Description......................................................................................................................... 1
Absolute Maximum Ratings ..................................................................................................... 3
Pin Configuration ................................................................................................................. 3
Order Information ................................................................................................................. 3
Electrical Characteristics ........................................................................................................ 4
Typical Performance Characteristics .......................................................................................... 6
Pin Functions ...................................................................................................................... 9
Block Diagram ....................................................................................................................10
Operation..........................................................................................................................11
Applications Information .......................................................................................................13
Typical Applications .............................................................................................................20
Package Description ............................................................................................................21
Revision History .................................................................................................................23
Typical Application ..............................................................................................................24
Related Parts .....................................................................................................................24
Rev D
2
For more information www.analog.com