LTC3607
Dual 600mA 15V Monolithic
Synchronous Step-Down
DC/DC Regulator
Description
Features
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High Efficiency: Up to 96%
Very Low Quiescent Current: 55µA Total
2.25MHz Constant Frequency Operation
Low Dropout Operation: 100% Duty Cycle
Low-Ripple (Typical 30mVP-P) Burst Mode®
Operation
Peak Current-Mode Control Architecture for Excellent
Line and Load Transient Response
Wide Voltage Input Range: 4.5V to 15V
600mA/Channel Rated Output Current
0.6V Reference Allows Low Output Voltages
±1.5% Output Voltage Accuracy
Ultralow Shutdown Current: IQ < 1µA
Internal Compensation
Power Good Outputs
Externally Frequency Synchronization (1MHz to 4MHz)
Independent Internal Soft-Start for Each Channel
Small 16-Lead Thermally Enhanced Thin QFN
(3mm × 3mm) and MSE Packages
The LTC®3607 is a 15V dual 600mA monolithic synchronous step-down regulator which has only 55µA quiescent
current. Intended for a variety of applications, including
dual lithium-ion battery products, it operates from a wide
4.5V to 15V input voltage range. It features a constant
2.25MHz switching frequency, enabling the use of tiny,
low cost capacitors and inductors 1mm or less in height.
Each output voltage is adjustable from 0.6V to VIN. The
internal synchronous power switches provide high efficiency without the need for external Schottky diodes.
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
ripple noise.
To further the maximize battery run time, the P-channel
MOSFETs are turned on continuously in dropout (100%
duty cycle). In shutdown, the device draws <1µA.
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, 5847554,
6580258, 6304066, 6476589, 6774611.
Applications
Dual Lithium-Ion Battery Supplies
Automotive Applications
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Typical Application
100
10µF
×2
PVIN1 SVIN PVIN2
RUN2
RUN1
SW1
LTC3607
SW2
22pF
4.7µH
22pF
887k
10µF
80
VFB2
VFB1
121k
GND
VOUT2
3.3V AT 600mA
549k
70
0.1
60
50
40
0.01
30
POWER LOSS (W)
4.7µH
VOUT1
5V AT 600mA
1
VIN = 12V
90
EFFICIENCY (%)
VIN 12V
Efficiency and Power Loss
vs Load Current
20
121k
10µF
VOUT = 5V
VOUT = 3.3V
10
3607 TA01a
0
1
10
100
LOAD CURRENT (mA)
0.001
1000
3607 TA01b
3607fb
For more information www.linear.com/LTC3607
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