Features Input voltage range of 4.5V–24V Constant On-Time No compensation needed Maximum Load Current of 3A Switching frequency of 100 kHz–500 kHz Constant frequency across input range TTL compatible shutdown thresholds Low standby current of 12 µA 130 mΩ internal MOSFET switch Description The LM2696 is a pulse width modulation (PWM) buck regulator capable of delivering up to 3A into a load. The control loop utilizes a constant on-time control scheme with input voltage feed forward. This provides a topology that has excellent transient response without the need for compensation. The input voltage feed forward ensures that a constant switching frequency is maintained across the entire VIN range. The LM2696 is capable of switching frequencies in the range of 100 kHz to 500 kHz. Combined with an integrated 130 mΩ high side NMOS switch the LM2696 can utilize small sized external components and provide high efficiency. An internal soft-start and power-good flag are also provided to allow for simple sequencing between multiple regulators. The LM2696 is available with an adjustable output in an exposed pad TSSOP-16 package. Applications High efficiency step-down switching regulators LCD Monitors Set-Top Boxes

WEBENCH® LM2696     Min   Max   Range     VIN – V    4.50 – 24.00V     VOUT V    1.29 – 20.00V     IOUT A    ≤ 3.00A     Ambient Temp °C    ≤ 100°C   Footprint BOM Cost Efficiency What are WEBENCH® tools?

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

Parameters Values Output Current 3000 mA Input Min Voltage 4.5 Volt Input Max Voltage 24 Volt Output Min 1.254 Volt Output Max 20 Volt Frequency Min 100 kHz Frequency Max 500 kHz Efficiency (peak) 90 % On/Off Pin Yes PowerGood / Error Flag Yes SoftStart Yes Sync Pin No Inverting Yes Flyback No RegType Switching Regulator Temperature Min -40 deg C Temperature Max 125 deg C Adjustable Output Yes Adj Switch Frequency Yes PWM Mode Constant on-time Topology Buck Special Features No compensation required, ultra-fast transient response, thermal shutdown Step-Down Yes Multiple Output Capability No Output Power Undefined Watt Output Voltage Undefined Volt Output Range 1.254V to 20V Switching Frequency 500 kHz Feedback Voltage 1.254 Volt Regulator Family Undefined Synchronous Rectification No

Datasheets

Title		Size	Date	Other Language
	LM2696 3A, Constant On Time Buck Regulator	421 Kbytes	18-May-09	日本語

Application Notes

Title		Size	Date	Other Language
	AN-1410: Application Note 1410 LM2696 Demonstration Board	566 Kbytes	14-Aug-06	中文

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2696MXA/NOPB LM2696MXA RoHS Status	TSSOP EXP PAD	Full production Lead Time: 8 weeks	Distributor Region Qty ARROW Worldwide 188 DIGI-KEY Worldwide 1415 FARNELL Europe and Asia 659 MOUSER Worldwide 148 NEWARK Americas 185 TAYLOR Americas 188	$1.70 each at 1K+ pcs	rail of 92
LM2696MXAX/NOPB RoHS Status	TSSOP EXP PAD	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0 RSL MICRO Asia Pacific 2500 TECHMOSA Asia Pacific 7500	$1.70 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 LM2696.

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 LM2696 is located at RoHS Status.

Part Number(s) (NSID)	Description	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM2696EVAL	3A, Constant On Time Buck Regulator	Full production	Distributor Region Qty DIGI-KEY Worldwide 0	$56.30 each	1
Description: LM2696EVAL: 3A, Constant On Time Buck Regulator Features: Input voltage range of 4.5V-24V Constant On-Time No compensation needed Maximum load current of 3A Switching frequency of 100 kHz-500kHz Constant frequency across input range TTL compatible shutdown thresholds Low standy current of 12µA 130mΩ internal MOSFET switch Contents: A fully assembled LM2696 evaluation board LM2696 datasheet LM2696 evaluation board appnote

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
LM2696MXA/NOPB LM2696MXA	56.396 56.606	TSSOP EXP PAD	16	1 1	260 260	Detail	Download	N/A	NSZXYTT 2696 MXA
LM2696MXAX/NOPB	56.396	TSSOP EXP PAD	16	1	260	Detail	Download	N/A	NSZXYTT 2696 MXA

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 LM2696.

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 LM2696 is located at RoHS Status.

CAD Symbols and Models Download LM2696 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM2696MXA	ABCD150	0	42680	0	0	6394000	1	1814314958
LM2696MXAX	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 LM2696.

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 LM2696 is located at RoHS Status.