LTC3548-2 Series

Dual Synchronous, Fixed/Adjustable Output, 2.25MHz Step-Down DC/DC Regulator

Catalog

Dual Synchronous, Fixed/Adjustable Output, 2.25MHz Step-Down DC/DC Regulator

Part	Output Configuration	Frequency - Switching	Current - Output	Package / Case	Topology	Operating Temperature [Max]	Operating Temperature [Min]	Function	Voltage - Output (Min/Fixed)	Output Type	Voltage - Input (Max) [Max]	Supplier Device Package	Voltage - Input (Min) [Min]	Voltage - Output (Max)	Number of Outputs	Mounting Type	Voltage - Output (Min/Fixed)	Voltage - Output (Max) [Max]	Package / Case	Voltage - Output (Min/Fixed) [Min]	Voltage - Output (Min/Fixed) [Max]	Output Type
Analog Devices LTC3548IDD#TRPBF	Positive	2.25 MHz	400 mA 800 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	85 °C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-DFN (3x3)	2.5 V	5 V	2	Surface Mount
Analog Devices LTC3548EDD-2#TRPBF	Positive	2.25 MHz	1.2 A 700 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	85 °C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable (Fixed)	5.5 V	10-DFN (3x3)	2.5 V		2	Surface Mount	1.8 V	5.5 V
Analog Devices LTC3548AIDD#TRPBF	Positive	2.25 MHz	400 mA 800 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	125 ¯C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-DFN (3x3)	2.5 V	5 V	2	Surface Mount
Analog Devices LTC3548EMSE#TRPBF	Positive	2.25 MHz	400 mA 800 mA	10-MSOP 10-TFSOP Exposed Pad	Buck Buck-Boost	85 °C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-MSOP-EP	2.5 V	5 V	2	Surface Mount			0.118 in 3 Lead
Analog Devices LTC3548AEDD#TRPBF	Positive	2.25 MHz	400 mA 800 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	125 ¯C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-DFN (3x3)	2.5 V	5 V	2	Surface Mount
Analog Devices LTC3548EDD-1#PBF	Positive	2.25 MHz	1.2 A 700 mA	10-WFDFN Exposed Pad	Buck	85 °C	-40 °C	Step-Down			5.5 V	10-DFN (3x3)	2.5 V		2	Surface Mount				1.575 V	1.8 V	1.81 mOhm
Analog Devices LTC3548EKD-1	Positive	2.25 MHz	1.2 A 700 mA	10-UFDFN Exposed Pad	Buck	85 °C	-40 °C	Step-Down			5.5 V	10-UTDFN (3x3)	2.5 V		2	Surface Mount				1.575 V	1.8 V	1.81 mOhm
Analog Devices LTC3548AIDD#PBF	Positive	2.25 MHz	400 mA 800 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	125 ¯C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-DFN (3x3)	2.5 V	5 V	2	Surface Mount
Analog Devices LTC3548EMSE#PBF	Positive	2.25 MHz	400 mA 800 mA	10-MSOP 10-TFSOP Exposed Pad	Buck Buck-Boost	85 °C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-MSOP-EP	2.5 V	5 V	2	Surface Mount			0.118 in 3 Lead
Analog Devices LTC3548EDD#TRPBF	Positive	2.25 MHz	400 mA 800 mA	10-WFDFN Exposed Pad	Buck Buck-Boost	85 °C	-40 °C	Step-Down Step-Up/Step-Down	0.6 V	Adjustable	5.5 V	10-DFN (3x3)	2.5 V	5 V	2	Surface Mount

Catalog

Dual Synchronous, Fixed/Adjustable Output, 2.25MHz Step-Down DC/DC Regulator

Key Features

• High Efficiency: Up to 95%

• Low Ripple (<35mVP-P) Burst Mode Operation; IQ= 40μA

• 2.25MHz Constant Frequency Operation

• High Switch Current: 0.7A and 1.2A

• No Schottky Diodes Required

• Low RDS(ON)Internal Switches: 0.35Ω

• Current Mode Operation for Excellent Line and Load Transient Response

• Short-Circuit Protected

• Low Dropout Operation: 100% Duty Cycle

• Ultralow Shutdown Current: IQ<1μA

• Output Voltages from 5V down to 0.6V

• Power-On Reset Output

• Externally Synchronizable Oscillator

• Optional External Soft-Start

• Small Thermally Enhanced MSOP and 3mm × 3mm DFN Packages

Description

The LTC3548-2 is a dual, constant frequency, synchronous step down DC/DC converter. Intended for low power applications, it operates from 2.5V to 5.5V input voltage range and has a constant 2.25MHz switching frequency, allowing the use of tiny, low cost capacitors and inductors with a profile ≤1.2mm. For channel 1, the output voltage is fixed at 1.8V/800mA; for channel 2, the output voltage is adjustable from 0.6V to VIN. Internal synchronous 0.35Ω, 1.2A/0.7A 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 noise ripple for low power efficiency. Burst Mode®operation provides high efficiency at light loads, while Pulse-Skip Mode provides low noise ripple at light loads.To further maximize battery run time, the P-channel MOSFETs are turned on continuously in dropout (100% duty cycle), and both channels draw a total quiescent current of only 40μA. In shutdown, the device draws <1μA.FeaturesLTC3548AImproved Burst Mode, Improved ESD, 2 Adjustable OutputsLTC3548-2One Fixed 1.8V Output, 1 AdjustableLTC3548-1Fixed 1.8V and 1.575V OutputsLTC35482 Adjustable OutputsApplicationsPDAs/Palmtop PCsDigital CamerasCellular PhonesPortable Media PlayersPC CardsWireless and DSL Modems