Features Ultra high efficiencies (95% possible) High efficiency over a 3A to milliamperes load range Synchronous switching of internal NMOS power FETs Wide input voltage range (4.5V to 18V) Output voltage adjustable from 1.5V to 16V Automatic low-power sleep mode Logic-controlled micropower shutdown (IQSD < 25 µA) Frequency adjustable up to 300 kHz Frequency synchronization with external signal Programmable soft-start Short-circuit current limiting Thermal shutdown Available in 24-lead Small-Outline package Description The LM2650 is a step-down DC/DC converter featuring high efficiency over a 3A to milliamperes load range. This feature makes the LM2650 an ideal fit in battery-powered applications that demand long battery life in both run and standby modes. The LM2650 also features a logic-controlled shutdown mode in which it draws at most 25µA from the input power supply. The LM2650 employs a fixed-frequency pulse-width modulation (PWM) and synchronous rectification to achieve very high efficiencies. In many applications, efficiencies reach 95%+ for loads around 1A and exceed 90% for moderate to heavy loads from 0.2A to 2A. A low-power hysteretic or "sleep" mode keeps efficiencies high at light loads. The LM2650 enters and exits sleep mode automatically as the load crosses "sleep in" and "sleep out" thresholds. The LM2650 provides nodes for programming both thresholds via external resistors. A logic input allows the user to override the automatic sleep feature and keep the LM2650 in PWM mode regardless of the load level. An optional soft-start feature limits current surges from the input power supply at start up and provides a simple means of sequencing multiple power supplies. Applications Notebook and palmtop personal computers Portable data terminals Modems Portable Instruments Global positioning devices (GPSs) Battery-powered digital devices

Also Recommended LM25576▲ 3A Integrated Switching Converter With 42V Max Input Voltage LM2679▲ 5A 40V Integrated Buck Regulator LM2853▲ 3A Integrated Synchronous Buck For Low Voltage Applications LM3100▲ 36V 1.5A Integrated Synchronous Buck Regulator LM5576▲ 3A Integrated Buck Regulator With 75V Input Capability

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

Datasheets

Title		Size	Date	Other Language
	LM2650 Synchronous Step-Down DC/DC Converter	215 Kbytes	1-Nov-00	日本語

Application Notes

Title		Size	Date	Other Language
	AN-1071: Application Note 1071 Information About the LM2650 Evaluation Board Rev. 1	105 Kbytes	4-Oct-04	日本語

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2650M-ADJ/NOPB LM2650M-ADJ RoHS Status	SOIC WIDE	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 50 AVNET-EM Worldwide 687 DIGI-KEY Worldwide 298 FARNELL Europe and Asia 122 MOUSER Worldwide 88 TAYLOR Americas 50	$3.93 each at 1K+ pcs	rail of 30
LM2650MX-ADJ/NOPB LM2650MX-ADJ RoHS Status	SOIC WIDE	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 4000 AVNET-EM Worldwide 1000 DIGI-KEY Worldwide 0 TAYLOR Americas 4000	$3.93 each at 1K+ pcs	reel of 1000

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 LM2650.

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 LM2650 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
LM2650M-ADJ/NOPB LM2650M-ADJ	628.76 630.001	SOIC WIDE	24	3 3	260 260	Detail	Download	N/A	NSUZXYTTE# LM2650M -ADJ
LM2650MX-ADJ/NOPB LM2650MX-ADJ	628.76 630.001	SOIC WIDE	24	3 3	260 260	Detail	Download	N/A	NSUZXYTTE# LM2650M -ADJ

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 LM2650.

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 LM2650 is located at RoHS Status.

CAD Symbols and Models Download LM2650 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM2650M-ADJ	LMDMOS	0	18295	0	0	2650000	2	751944735
LM2650MX-ADJ	LMDMOS	0	18295	0	0	2650000	2	751944735

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 LM2650.

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 LM2650 is located at RoHS Status.