Features Input power from 1V to 16V Output voltage adjustable down to 0.6V Power Good flag, adjustable soft-start and output enable for easy power sequencing Reference Accuracy: 1.5% (0°C - 125°C) Current limit without sense resistor Soft start Switching frequency from 50 kHz to 2 MHz 40ns typical minimum on-time TSSOP-14 package Description The LM2742 is a high-speed, synchronous, switching regulator controller. It is intended to control currents of 0.7A to 20A with up to 95% conversion efficiencies. Power up and down sequencing is achieved with the power-good flag, adjustable soft-start and output enable features. The LM2742 operates from a low-current 5V bias and can convert from a 1V to 16V power rail. The part utilizes a fixed-frequency, voltage-mode, PWM control architecture and the switching frequency is adjustable from 50kHz to 2MHz by setting the value of an external resistor. Current limit is achieved by monitoring the voltage drop across the on-resistance of the low-side MOSFET, which enables on-times on the order of 40ns, one of the best in the industry. The wide range of operating frequencies gives the power supply designer the flexibility to fine-tune component size, cost, noise and efficiency. The adaptive, non-overlapping MOSFET gate-drivers and high-side bootstrap structure helps to further maximize efficiency. The high-side power FET drain voltage can be from 1V to 16V and the output voltage is adjustable down to 0.6V. Applications POL power supply modules Cable Modems Set-Top Boxes/ Home Gateways DDR Core Power High-Efficiency Distributed Power Local Regulation of Core Power

Also Recommended LM2737▲ Identical Except That The Low-side FET Is On During Shutdown LM2743▲ Vcc Down To 3.0V LM2745▲ Has Clock Syncronization (Sync Pin), Pre-Biased Load Startup And 3.0V Min Vcc LM5115 75V Max Vin Sync Buck Controller

Typical Application click for larger image	Block Diagram click for larger image
Typical Performance click for larger image

Datasheets

Title		Size	Date	Other Language
	LM2742 N-Channel FET Synchronous Buck Regulator Controller for Low Output Voltages	657 Kbytes	31-Oct-07	日本語

Application Notes

Title		Size	Date	Other Language
	AN-1325: Application Note 1325 LM2742 Evaluation Board	607 Kbytes	1-Apr-04
	AN-1603: Application Note 1603 LM274X Reference Designs	431 Kbytes	6-Dec-07	中文
	AN-1437: Application Note 1437 Current Limit Foldback Improves Short Circuit Protection in LM2743/44 Family	470 Kbytes	25-May-06	中文

Other Technical Documents

Title		Type	Date
	Power Management Considerations for FPGAs and ASICs	Power Designer	2007-03-22
	Optimizing Power Controller Designs through Effective Utilization of Performance Features (Adj Frequency & Sync, Ext Ref, Tracking, & Precision Enable)	Power Designer	2008-04-24

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2742MTC/NOPB LM2742MTC RoHS Status	TSSOP	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 93 DIGI-KEY Worldwide 839 MOUSER Worldwide 376 RS COMPONENTS Worldwide 25 TAYLOR Americas 93	$1.25 each at 1K+ pcs	rail of 94
LM2742MTCX/NOPB LM2742MTCX RoHS Status	TSSOP	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 5000 DIGI-KEY Worldwide 0 MOUSER Worldwide 2470 TAYLOR Americas 5000	$1.25 each at 1K+ pcs	reel of 2500

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2742.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2742 is located at RoHS Status.

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM2742MTC/NOPB LM2742MTC	53.783 54.004	TSSOP	14	1 1	260 260	Detail	Download	N/A	NSZXYTT 2742 MTC
LM2742MTCX/NOPB LM2742MTCX	53.783 54.004	TSSOP	14	1 1	260 260	Detail	Download	N/A	NSZXYTT 2742 MTC

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2742.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2742 is located at RoHS Status.

Design Tools

Title	Size	Date
Power Reference Design Library

CAD Symbols and Models Download LM2742 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM2742MTC	ABCD150	0	42680	0	0	6394000	1	1814314958
LM2742MTCX	ABCD150	0	42680	0	0	6394000	1	1814314958

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LM2742.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LM2742 is located at RoHS Status.