Specification	LM3668SD-2833/NOPB

Current - Output	1 A
Frequency - Switching	2.2 MHz
Function	Step-Up/Step-Down
Mounting Type	Surface Mount
Number of Outputs	1
Operating Temperature [Max]	85 °C
Operating Temperature [Min]	-40 °C
Output Configuration	Positive
Output Type	Programmable
Package / Case	12-WFDFN Exposed Pad
Supplier Device Package	12-WSON (3x3)
Synchronous Rectifier	True
Topology	Buck-Boost
Voltage - Input (Max) [Max]	5.5 V
Voltage - Input (Min) [Min]	2.5 V
Voltage - Output (Min/Fixed)	3.3 V, 2.8 V

LM3668 Series

Part	Topology	Number of Outputs	Voltage - Output (Min/Fixed)	Output Type	Voltage - Input (Max) [Max]	Function	Voltage - Input (Min) [Min]	Package / Case	Supplier Device Package	Mounting Type	Current - Output	Output Configuration	Operating Temperature [Max]	Operating Temperature [Min]	Frequency - Switching	Voltage - Output (Min/Fixed)	Qualification	Grade	Frequency - Switching [Min]	Frequency - Switching [Max]	Board Type	Voltage - Input [Min]	Voltage - Input [Max]	Regulator Topology	Outputs and Type	Outputs and Type	Supplied Contents	Utilized IC / Part	Main Purpose	Voltage - Output	Output Type
Texas Instruments LM3668SDX-2833/NOPB	Buck-Boost	1	2.8 V 3.3 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz
Texas Instruments LM3668SD-4550/NOPB	Buck-Boost	1	4.5 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz	5 V
Texas Instruments LM3668QDNTRQ1	Buck-Boost	1	4.5 V	Adjustable	5.5 V	Step-Up/Step-Down	2.7 V	12-WFDFN Exposed Pad	12-WSON (4x4)	Surface Mount	1 A	Positive	125 ¯C	-40 °C		5 V	AEC-Q100	Automotive	1.9 MHz	2.5 MHz
Texas Instruments LM3668SD-3034/NOPB	Buck-Boost	1	3 V 3.4 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz
Texas Instruments LM3668SD-2833/NOPB	Buck-Boost	1	2.8 V 3.3 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz
Texas Instruments LM3668SD-2833EV/NOPB											1 A				2.2 MHz						Fully Populated	2.5 V	5.5 V	Buck-Boost	Non-Isolated	1	Board(s)	LM3668	DC/DC Step Up or Down	2.8 V 3.3 V
Texas Instruments LM3668SD-4550EV											1 A				2.2 MHz						Fully Populated	2.5 V	5.5 V	Buck-Boost	Non-Isolated	1	Board(s)	LM3668	DC/DC Step Up or Down	4.5 V 5 V
Texas Instruments LM3668SDX-3034/NOPB	Buck-Boost	1	3 V 3.4 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz
Texas Instruments LM3668SDX-4550/NOPB	Buck-Boost	1	4.5 V	Programmable	5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz	5 V
Texas Instruments LM3668SD-3.3/NOPB	Buck-Boost	1	3.3 V		5.5 V	Step-Up/Step-Down	2.5 V	12-WFDFN Exposed Pad	12-WSON (3x3)	Surface Mount	1 A	Positive	85 °C	-40 °C	2.2 MHz																1.81 mOhm

Pricing

Prices provided here are for design reference only. For realtime values and availability, please visit the distributors directly

Distributor	Package	Quantity	$

Digikey	Cut Tape (CT)	1	$ 2.80
		10	$ 2.51
		25	$ 2.38
		100	$ 2.06
		250	$ 1.95
		500	$ 1.75
	Digi-Reel®	1	$ 2.80
		10	$ 2.51
		25	$ 2.38
		100	$ 2.06
		250	$ 1.95
		500	$ 1.75
	Tape & Reel (TR)	1000	$ 1.48
		2000	$ 1.41
		5000	$ 1.35
Texas Instruments	SMALL T&R	1	$ 2.33
		100	$ 2.04
		250	$ 1.43
		1000	$ 1.15

Description

General part information

LM3668 Series

The LM3668 is a synchronous buck-boost DC-DC converter optimized for powering low voltage circuits from a Li-Ion battery and input voltage rails between 2.5 V and 5.5 V. It has the capability to support up to 1-A output current over the output voltage range. The LM3668 regulates the output voltage over the complete input voltage range by automatically switching between buck or boost modes depending on the input voltage.

The LM3668 has 2 N-channel MOSFETS and 2 P-channel MOSFETS arranged in a topology that provides continuous operation through the buck and boost operating modes. There is a MODE pin that allows the user to choose between an intelligent automatic PFM-PWM mode operation and forced PWM operation. During PWM mode, a fixed-frequency 2.2 MHz (typical) is used. PWM mode drives load up to 1 A. Hysteretic PFM mode extends the battery life through reduction of the quiescent current to 45 µA (typical) at light loads during system standby. Internal synchronous rectification provides high efficiency. In shutdown mode (EN pin pulled low), the device turns off and reduces battery consumption to 0.01 µA (typical).

A high switching frequency of 2.2 MHz (typical) allows the use of tiny surface-mount components including a 2.2-µH inductor, a 10-µF input capacitor, and a 22-µF output capacitor.

Documents

Technical documentation and resources

LM3668 1-A, High-Efficiency Dual-Mode Single-Inductor Buck-Boost DC-DC Converter datasheet (Rev. O)

Data sheet