Step-Down DC/DC Regulator
n High Efﬁciency: Up to 95%
n 1.5A/1A Guaranteed Minimum Output Current
n Synchronizable to External Clock
n No Schottky Diodes Required
n Programmable Frequency Operation: 1.5MHz or
Adjustable From 0.6MHz to 4MHz
n Low Ripple (<35mVP-P) BurstMode® Operation
IQ: 125μA in Sleep
n Low RDS(ON) Internal Switches
n Short-Circuit Protected
n VIN: 2.25V to 5.5V
n Current Mode Operation for Excellent Line and Load
n Ultralow Shutdown Current: IQ < 1μA
n Low Dropout Operation: 100% Duty Cycle
n Power Good Ouput
n Phase Pin Selects 2nd Channel Phase Relationship
with Respect to 1st Channel
n Internal Soft-Start with Individual Run Pin Control
n Available in Small Thermally Enhanced
(5mm × 3mm) DFN and 20-Lead TSSOP Packages
n GPS/Navigation Systems
n Automotive Instrumentation
n PC Cards
n Industrial Power Supplies
n General Purpose Point of Load DC/DC
The LTC®3417A-2 is a dual constant frequency, synchro-
nous step-down DC/DC converter. Intended for medium
power applications, it operates from a 2.25V to 5.5V input
voltage range and has a constant programmable switching
frequency, allowing the use of tiny, low cost capacitors
and inductors 2mm or less in height. Each output voltage
is adjustable from 0.8V to 5V. Internal synchronous, low
RDS(ON) power switches provide high efﬁciency without
the need for external Schottky diodes.
A user selectable mode input allows the user to trade
off ripple voltage for light load efﬁciency. Burst Mode
operation provides high efﬁciency at light loads, while
Pulse Skip mode provides low ripple noise at light loads.
A phase mode pin allows the second channel to operate
in-phase or 180° out-of-phase with respect to channel 1.
Out-of-phase operation produces lower RMS current on
VIN and thus lower stress on the input capacitor.
To further maximize battery life, the P-channel MOSFETs
are turned on continuously in dropout (100% duty cycle)
and both channels draw a total quiescent current of only
100μA. In shutdown, the device draws <1μA.
L, LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners. Protected by U.S. Patents
including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131, 6144194.
2.5V TO 5.5V
(Burst Mode Operation)
100 REFER TO FIGURE 4
VIN = 3.6V
VOUT = 2.5V
FREQ = 1MHz 0.0001
LOAD CURRENT (A)