LTC3607_15 Datasheet, PDF (1/20 Pages) Linear Technology – Dual 600mA 15V Monolithic Synchronous Step-Down DC/DC Regulator

Features
n _{High Efficiency: Up to 96%}
n _{Very Low Quiescent Current: 55µA Total}
n _{2.25MHz Constant Frequency Operation}
n _{Low Dropout Operation: 100% Duty Cycle}
n _{Low-Ripple (Typical 30mVP-P) Burst Mode}®
Operation
n _{Peak Current-Mode Control Architecture for Excellent}
Line and Load Transient Response
n _{Wide Voltage Input Range: 4.5V to 15V}
n _{600mA/Channel Rated Output Current}
n _{0.6V Reference Allows Low Output Voltages}
n _{±1.5% Output Voltage Accuracy}
n _{Ultralow Shutdown Current: IQ < 1µA}
n _{Internal Compensation}
n _{Power Good Outputs}
n _{Externally Frequency Synchronization (1MHz to 4MHz)}
n _{Independent Internal Soft-Start for Each Channel}
n _{Small 16-Lead Thermally Enhanced Thin QFN}
(3mm × 3mm) and MSE Packages
Applications
n _{Dual Lithium-Ion Battery Supplies}
n _{Automotive Applications}
n _Servers
LTC3607
Dual 600mA 15V Monolithic
Synchronous Step-Down
DC/DC Regulator
Description
The LTC^®3607 is a 15V dual 600mA monolithic synchro-
nous 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 V_IN. The
internal synchronous power switches provide high ef-
ficiency 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.
Typical Application
V_IN 12V
V_OUT1
5V AT 600mA
10µF
×2
4.7µH
22pF
PVIN1 SVIN PVIN2
RUN1
RUN2
LTC3607
SW1
SW2
4.7µH
22pF
887k
10µF
V_FB1
121k
V_FB2
GND
549k
121k
V_OUT2
3.3V AT 600mA
10µF
3607 TA01a
For more information www.linear.com/LTC3607
Efficiency and Power Loss
vs Load Current
100
1
V_IN = 12V
90
80
70
0.1
60
50
40
30
0.01
20
10
V_OUT = 5V
V_OUT = 3.3V
0
0.001
1
10
100
1000
LOAD CURRENT (mA)
3607 TA01b
3607fb
1