Features Ultra low dropout voltage Stable with selected ceramic capacitors Low ground pin current Load regulation of 0.06% 10nA quiescent current in shutdown mode Guaranteed output current of 1.5A DC Available in TO-263, TO-220 and SOT-223 packages Overtemperature/overcurrent protection −40°C to +125°C junction temperature range Description The LP3855-ADJ fast ultra low-dropout linear regulators operate from a +2.5V to +7.0V input supply. These ultra low dropout linear regulators respond very quickly to step changes in load, which makes them suitable for low voltage microprocessor applications. The LP3855-ADJ is developed on a CMOS process which allows low quiescent current operation independent of output load current. This CMOS process also allows the LP3855-ADJ to operate under extremely low dropout conditions. Dropout Voltage: Ultra low dropout voltage; typically 24mV at 150mA load current and 240mV at 1.5A load current. Ground Pin Current: Typically 4mA at 1.5A load current. Shutdown Mode: Typically 10nA quiescent current when the shutdown pin is pulled low. Adjustable Output Voltage: The output voltage may be programmed via two external resistors. Applications Microprocessor power supplies GTL, GTL+, BTL, and SSTL bus terminators Power supplies for DSPs SCSI terminator Post regulators High efficiency linear regulators Battery chargers Other battery powered applications

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

Datasheets

Title		Size	Date	Other Language
	LP3855-ADJ 1.5A Fast Response Ultra Low Dropout Linear Regulators	349 Kbytes	9-Mar-11

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LP3855EMP-ADJ/NOPB LP3855EMP-ADJ RoHS Status	SOT-223	Full production Lead Time: 16 weeks	Distributor Region Qty DIGI-KEY Worldwide 2005 FARNELL Europe and Asia 1062 MOUSER Worldwide 1000 NEWARK Americas 682 RS COMPONENTS Worldwide 16	$1.85 each at 1K+ pcs	reel of 1000
LP3855EMPX-ADJ/NOPB LP3855EMPX-ADJ RoHS Status	SOT-223	Full production Lead Time: 16 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$1.85 each at 1K+ pcs	reel of 2000
LP3855ES-ADJ/NOPB LP3855ES-ADJ RoHS Status	TO-263	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 1183 AVNET-EM Worldwide 74 DIGI-KEY Worldwide 149 RS COMPONENTS Worldwide 30 TAYLOR Americas 1183	$1.85 each at 1K+ pcs	rail of 45
LP3855ESX-ADJ/NOPB LP3855ESX-ADJ RoHS Status	TO-263	Full production Lead Time: 6 weeks	Distributor Region Qty AVNET-EM Worldwide 500 DIGI-KEY Worldwide 0	$1.85 each at 1K+ pcs	reel of 500
LP3855ET-ADJ/NOPB RoHS Status	TO-220	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 180 AVNET-EM Worldwide 243 DIGI-KEY Worldwide 376 RS COMPONENTS Worldwide 5 TAYLOR Americas 180	$1.85 each at 1K+ pcs	rail of 45

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 LP3855-ADJ.

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 LP3855-ADJ 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
LP3855EMP-ADJ/NOPB LP3855EMP-ADJ	119.55 120.002	SOT-223	5	1 1	260 260	Detail	N/A	N/A	XYTT LJ3B
LP3855EMPX-ADJ/NOPB LP3855EMPX-ADJ	119.55 120.002	SOT-223	5	1 1	260 260	Detail	N/A	N/A	XYTT LJ3B
LP3855ES-ADJ/NOPB LP3855ES-ADJ	1448.647 1449.868	TO-263	5	3 3	245 235	Detail	N/A	N/A	NSUZXYTTE# LP3855ES -ADJ
LP3855ESX-ADJ/NOPB LP3855ESX-ADJ	1448.647 1449.868	TO-263	5	3 3	245 235	Detail	N/A	N/A	NSUZXYTTE# LP3855ES -ADJ
LP3855ET-ADJ/NOPB	1957.896	TO-220	5	1	NA	Detail	N/A	N/A	NSUZXYTTE# LP3855ET -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 LP3855-ADJ.

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 LP3855-ADJ is located at RoHS Status.

CAD Symbols and Models N/A

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LP3855EMP-ADJ	CS065	2	47473	43	0	5527000	1	1568301341
LP3855EMPX-ADJ	CS065	2	47473	43	0	5527000	1	1568301341
LP3855ES-ADJ	CS065	2	47473	43	0	5527000	1	1568301341
LP3855ESX-ADJ	CS065	2	47473	43	0	5527000	1	1568301341
LP3855ET-ADJ	CS065	2	47473	43	0	5527000	1	1568301341

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 LP3855-ADJ.

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 LP3855-ADJ is located at RoHS Status.