Features Small Mini-SO8 Package (Half the Footprint of Standard 8-Pin SO Package) 1.09 mm Package Height Up to 2 MHz Switching Frequency 1.2V to 14V Input Voltage 1.24V - 14V Adjustable Output Voltage Up to 1A Load Current 0.17 Internal MOSFET Up to 90% Regulator Efficiency 80 µA Typical Operating Current <2.5µA Guaranteed Supply Current In Shutdown Description The LM2621 is a high efficiency, step-up DC-DC switching regulator for battery-powered and low input voltage systems. It accepts an input voltage between 1.2V and 14V and converts it into a regulated output voltage. The output voltage can be adjusted between 1.24V and 14V. It has an internal 0.17 N-Channel MOSFET power switch. Efficiencies up to 90% are achievable using the LM2621. The high switching frequency (adjustable up to 2MHz) of the LM2621 allows for tiny surface mount inductors and capacitors. Because of the unique constant-duty-cycle gated oscillator topology very high efficiencies are realized over a wide load range. The supply current is reduced to 80µA because of the BiCMOS process technology. In the shutdown mode, the supply current is less than 2.5µA. The LM2621 is available in a Mini-SO-8 package. This package uses half the board area of a standard 8-pin SO and has a height of just 1.09 mm. Applications PDAs, Cellular Phones 2-Cell and 3-Cell Battery-Operated Equipment PCMCIA Cards, Memory Cards Flash Memory Programming TFT/LCD Applications 3.3V to 5.0V Conversion GPS Devices Two-Way Pagers Palmtop Computers Hand-Held Instruments

Also Recommended LM2623▲ Operates With Input Voltages As Low As 0.8V LM2698▲ Wider Switch Voltage , Fixed Frequency LM27313▲ Fixed Frequency , Smaller Package LM2733▲ 1A 40V Switch Boost Regulator In SOT-23 LM3224▲ Wider Switch Voltage , Fixed Frequency LM2704 Low Power 500mA Switch Boost In SOT-23

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

Parameters / Values	LM2621	LM2623	LM2698	LM27313	LM2733	LM3224
Output Range	1.24V to 14V	1.24V to 14V	2.2V to 17V	4 to 28V	Vin to 40V	Vin to 20V
Switch Current	2.85 Amp	1.2, 2.2 Amp	1.35 Amp	1 Amp	1 Amp	2.6 Amp
Input Min Voltage	1.2 Volt	0.8 Volt	2.2 Volt	2.7 Volt	2.7 Volt	2.7 Volt
Input Max Voltage	14 Volt	14 Volt	12 Volt	14 Volt	14 Volt	7 Volt
Frequency Max	2000 kHz	2000 kHz	1250 kHz	1600 kHz	600, 1600 kHz	1250 kHz
Output Min	1.24 Volt	1.24 Volt	2.2 Volt	4 Volt	3 Volt	Undefined Volt
Output Max	14 Volt	14 Volt	17 Volt	28 Volt	40 Volt	20 Volt
Efficiency (peak)	90 %	90 %	Undefined %	90 %	Undefined %	90 %
Sync Pin	No	No	No	No	No	No
Adj Switch Frequency	Yes	Yes	Yes	No	No	Yes
Frequency Min	300 kHz	300 kHz	600 kHz	1600 kHz	600, 1600 kHz	615 kHz
On/Off Pin	Yes	Yes	Yes	Yes	Yes	Yes
PowerGood / Error Flag	No	No	No	No	No	No
SoftStart	No	No	No	No		Yes
Special Features	Constant duty cycle gated oscillator	Ratio-adaptive gated oscillator	2.5% output voltage accuracy	Undefined		Pin-selected switching frequency, External compensation, Ceramic cap stable, Flat panel display power, High current LED driver
PWM Mode	Gated Oscillator	Gated oscillator	Current	Undefined	Current	Current
Topology	Boost, Flyback	Boost, Flyback	Boost	CV boost	Boost	Boost
Step-Up	Yes	Yes	Yes	Yes	Yes	Yes
Inverting	No	No	No	No	No	No
Flyback	Yes	Yes	No	No	No	Yes
RegType	Switching Regulator	Switching Regulator	Switching Regulator	Switching Regulator	Switching Regulator	Switching Regulator
Adjustable Output	Yes	Yes	Yes	Yes	Yes	Yes
Output Power	Undefined Watt	Undefined Watt	Undefined Watt	2.5 Watt	Undefined Watt	Undefined Watt
Temperature Min	-40 deg C	-40 deg C	-40 deg C	-40 deg C	-40 deg C	-40 deg C
Temperature Max	85 deg C	85 deg C	125 deg C	125 deg C	125 deg C	125 deg C
Quiescent Current	0.08 mA	0.08 mA	1.3 mA	2.1 mA	1.1, 2.1 mA	1.3 mA

Datasheets

Title		Size	Date	Other Language
	LM2621 Low Input Voltage, Step-Up DC-DC	656 Kbytes	25-Mar-05	日本語

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2621MM/NOPB LM2621MM RoHS Status	MINI SOIC	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 1800 AVNET-EM Worldwide 1185 CEAC Asia Pacific 40000 DIGI-KEY Worldwide 2717 FARNELL Europe and Asia 1218 MOUSER Worldwide 412 NEWARK Americas 465 RS COMPONENTS Worldwide 275 TAYLOR Americas 15308	$0.71 each at 1K+ pcs	reel of 1000
LM2621MMX/NOPB LM2621MMX RoHS Status	MINI SOIC	Full production Lead Time: 8 weeks	Distributor Region Qty ARROW Worldwide 3500 AVNET-EM Worldwide 3500 DIGI-KEY Worldwide 0 MOUSER Worldwide 3455 TAYLOR Americas 3500	$0.71 each at 1K+ pcs	reel of 3500

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 LM2621.

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 LM2621 is located at RoHS Status.

Part Number(s) (NSID)	Description	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2621EVAL/NOPB	Low Input Voltage, Step-Up DC-DC	Full production Lead Free (RoHS)	Distributor Region Qty DIGI-KEY Worldwide 0	$30.00 each	1
Features: 1MHz Switching frequency minimizes board size 0.1uA shutdown current maximizes battery life Start-up at 1.1V; operational down to 0.65V Step-up or SEPIC applications MSOP-8 package - half the size of 8-Pin SO Contents: LM2621MM Evaluation Board Switch to National the Future of Power Management CD ROM LM2621 Datasheet

National Semiconductor follows the provisions of the Product Stewardship Guide for Customers (CSP-9-111C1) and Banned Substances and Materials of Interest Specification (CSP-9-111S2) for regulatory environmental compliance. Details may be found at: www.national.com/en/packaging/greennopb.html. Lead free products are RoHS compliant.

Lead Free product status is available through the search tool located here

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LM2621MM/NOPB LM2621MM	29.851 30.002	MINI SOIC	8	1 1	260 260	Detail	Download	N/A	ZXTT S06A
LM2621MMX/NOPB LM2621MMX	29.851 30.002	MINI SOIC	8	1 1	260 260	Detail	Download	N/A	ZXTT S06A

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 LM2621.

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 LM2621 is located at RoHS Status.

Design Tools

Title	Size	Date
Power Reference Design Library

Reference Design

LM2621 Reference Design - Sepic Converter for Battery Applications: 2.7-5.5V Input, 3.3V @ 0.65A Output

CAD Symbols and Models Download LM2621 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM2621MM	ABCD150	0	42680	0	0	6394000	1	1814314958
LM2621MMX	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 LM2621.

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 LM2621 is located at RoHS Status.