Features Internal start-up bias regulator 3A compound main gate driver Programmable line under-voltage lockout (UVLO) with adjustable hysteresis Voltage mode control with feed-forward Adjustable dual mode over-current protection Programmable overlap or deadtime between the main and active clamp outputs Volt x Second maximum duty cycle clamp Programmable soft-start Current sense leading edge blanking Single resistor programmable oscillator Oscillator up / down sync capability Precision 5V reference Thermal shutdown Description The LM5025B is a functional variant of the LM5025 active clamp PWM controller. The functional differences of the LM5025B are as follows: The maximum PWM duty cycle is limited to less than 75% to reduce voltage stress on the power MOSFETs. The CS2 hiccup mode threshold is increased to 0.5V The CS2 filter discharge device is disabled The VCC regulator continues to operate when the line UVLO is below the threshold of normal operation The VREF regulator is switched off when the line UVLO input falls below the operating threshold The internal 5k COMP pin pull-up resistor is removed The LM5025B PWM controller contains all of the features necessary to implement power converters utilizing the Active Clamp / Reset technique. With the active clamp technique, higher efficiencies and greater power densities can be realized compared to conventional catch winding or RDC clamp / reset techniques. Two control outputs are provided, the main power switch control (OUT_A) and the active clamp switch control (OUT_B). The two internal compound gate drivers parallel both MOS and Bipolar devices, providing superior gate drive characteristics. This controller is designed for high-speed operation including an oscillator frequency range up to 1MHz and total PWM and current sense propagation delays less than 100ns. The LM5025B includes a high-voltage start-up regulator that operates over a wide input range of 13V to 100V. Additional features include: Line Under Voltage Lockout (UVLO), softstart, oscillator UP/DOWN sync capability, precision reference and thermal shutdown.

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

Datasheets

Title		Size	Date	Other Language
	LM5025B Active Clamp Voltage Mode PWM Controller	710 Kbytes	3-Mar-06

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LM5025BMTC/NOPB RoHS Status	TSSOP	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0 MOUSER Worldwide 276	$1.30 each at 1K+ pcs	rail of 92
LM5025BMTCX/NOPB RoHS Status	TSSOP	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$1.30 each at 1K+ pcs	reel of 2500
LM5025BSD/NOPB LM5025BSD RoHS Status	LLP	Full production Lead Time: 6 weeks	Distributor Region Qty AVNET-EM Worldwide 1000 DIGI-KEY Worldwide 560 MOUSER Worldwide 1000	$1.30 each at 1K+ pcs	reel of 1000
LM5025BSDX RoHS Status	LLP	Full production Lead Time: 16 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$1.30 each at 1K+ pcs	reel of 4500

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 LM5025B.

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 LM5025B 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
LM5025BMTC/NOPB	56.74	TSSOP	16	1	260	Detail	Download	spice file	NSUZXYTT L5025B MTC
LM5025BMTCX/NOPB	56.74	TSSOP	16	1	260	Detail	Download	spice file	NSUZXYTT L5025B MTC
LM5025BSD/NOPB LM5025BSD	64.927 65.192	LLP	16	1 1	260 260	Detail	Download	spice file	NS UZXYTT 5025BSD
LM5025BSDX	65.192	LLP	16	1	260	Detail	Download	spice file	NS UZXYTT 5025BSD

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 LM5025B.

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 LM5025B is located at RoHS Status.

CAD Symbols and Models Download LM5025B CAD Symbols

Models spice file

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM5025BMTC	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM5025BMTCX	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM5025BSD	ABCD150XV1	0	3868	0	0	2595000	2	736338335
LM5025BSDX	ABCD150XV1	0	3868	0	0	2595000	2	736338335

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 LM5025B.

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 LM5025B is located at RoHS Status.