LTC3646/LTC3646-1 - 40V, 1A Synchronous Step-Down Converter

The LTC®3646 is a high efficiency, step-down DC/DC converter with internal high side and synchronous power FETs. It draws only 140μA typical DC supply current in Burst Mode operation at no load while maintaining output voltage regulation.

The LTC3646 can supply up to a 1A load, and its combination of Burst Mode operation, integrated power switches and low quiescent current provides high efficiency over a broad range of load currents. Alternatively, it can be used in forced continuous mode for ripple sensitive applications.

The LTC3646 has a wide 4.0V to 40V input range and its patented controlled on-time architecture and 0.6V reference voltage allow for large step-down ratios without the risk of output overvoltage. The frequency may be set between 200kHz and 3.0MHz with a program resistor or synchronized to an external clock.

The internal soft-start, short-circuit protection and voltage rating make the LTC3646 a robust part ideal for high voltage applications.

Features

Wide Input Voltage Range: 4.0V to 40V
1A Guaranteed Output Current
High Efficiency: Up to 95%
Wide Output Voltage Range LTC3646: 2.0V to 30V LTC3646-1: 0.6V to 15V
±1% Accurate Reference Voltage
Internal or External Compensation
Switching Frequency Adjustable and Synchronizable: 200kHz to 3MHz
Selectable High Efficiency Burst Mode® Operation or Forced Continuous Mode
14 Lead 3mm × 4mm DFN or Thermally Enhanced
16-Lead MSOP Packages

Typical Application

Applications

Point of Load Power Supply
Intermediate Bus Power
Automotive Applications

Packaging

**Order Information**
Part Number	Package	Temp	Price(1-99)	Price (1k)*
LTC3646EDE-1#PBF	4x3 DFN-14	E	$4.07	$2.85
LTC3646EDE-1#TRPBF	4x3 DFN-14	E		$2.91
LTC3646EDE#PBF	4x3 DFN-14	E	$4.07	$2.85
LTC3646EDE#TRPBF	4x3 DFN-14	E		$2.91
LTC3646EMSE-1#PBF	MS-16E	E	$4.07	$2.85
LTC3646EMSE-1#TRPBF	MS-16E	E		$2.91
LTC3646EMSE#PBF	MS-16E	E	$4.07	$2.85
LTC3646EMSE#TRPBF	MS-16E	E		$2.91
LTC3646HDE-1#PBF	4x3 DFN-14	H	$4.84	$3.39
LTC3646HDE-1#TRPBF	4x3 DFN-14	H		$3.45
LTC3646HDE#PBF	4x3 DFN-14	H	$4.84	$3.39
LTC3646HDE#TRPBF	4x3 DFN-14	H		$3.45
LTC3646HMSE-1#PBF	MS-16E	H	$4.84	$3.39
LTC3646HMSE-1#TRPBF	MS-16E	H		$3.45
LTC3646HMSE#PBF	MS-16E	H	$4.84	$3.39
LTC3646HMSE#TRPBF	MS-16E	H		$3.45
LTC3646IDE-1#PBF	4x3 DFN-14	I	$4.49	$3.14
LTC3646IDE-1#TRPBF	4x3 DFN-14	I		$3.20
LTC3646IDE#PBF	4x3 DFN-14	I	$4.49	$3.14
LTC3646IDE#TRPBF	4x3 DFN-14	I		$3.20
LTC3646IMSE-1#PBF	MS-16E	I	$4.49	$3.14
LTC3646IMSE-1#TRPBF	MS-16E	I		$3.20
LTC3646IMSE#PBF	MS-16E	I	$4.49	$3.14
LTC3646IMSE#TRPBF	MS-16E	I		$3.20

Demo Boards


Part Number	Description	Price
DC1731A-A	LTC3646 Demo Board (DFN) I 4V ≤ VIN ≤ 40V, Vout = 3.3V or 5V @ 1A	$150.00
DC1731A-B	LTC3646-1 Demo Board (DFN) \| 4V ≤ VIN ≤ 40V, Vout = 3.3V or 5V @ 1A	$150.00
DC1820A-A	LTC3646 Demo Board (MSOP) \| 4V ≤ VIN ≤ 40V, Vout = 3.3V or 5V @ 1A	$150.00
DC1820A-B	LTC3646-1 Demo Board (MSOP) \| 4V ≤ VIN ≤ 40V, Vout = 3.3V or 5V @ 1A	Contact Factory