LP38856 - 3A Fast-Response High-Accuracy LDO Linear Regulator with Enable

LP38856 - 3A Fast-Response High-Accuracy LDO Linear Regulator with Enable from the PowerWise® Family

Datasheet	Packaging	Samples & Pricing	Eval. Boards	Reliability	Design Tools	Application Notes	Knowledge Base

Features

•	Standard V_OUT values of 0.8V and 1.2V
•	Wide V_BIAS Supply operating range of 3.0V to 5.5V
•	Stable with 10 µF ceramic capacitors
•	Dropout voltage of 240 mV (typical) at 3A load current
•	Precision Output Voltage across all line and load conditions:
•	±1.0% for T_J = 25°C
•	±2.0% for 0°C ≤ T_J ≤ +125°C
•	±3.0% for -40°C ≤ T_J ≤ +125°C
•	Over-Temperature and Over-Current protection
•	Available in 5 lead TO-220 and TO-263 packages
•	Custom V_OUT values between 0.8V and 1.2V are available
•	-40°C to +125°C Operating Temperature Range

General Description

The LP38856 is a high-current, fast-response regulator which can maintain output voltage regulation with an extremely low input to output voltage drop. More...

Applications

•	ASIC Power Supplies In: - Desktops, Notebooks, and Graphics Cards, Servers - Gaming Set Top Boxes, Printers and Copiers
•	Server Core and I/O Supplies
•	DSP and FPGA Power Supplies
•	SMPS Post-Regulator

Typical Application

*click for larger image

Parameters Values

Output Current 3000 mA

Output Min 1.2, 0.8 Volt

Input Min Voltage 1.55, 1.15 Volt

Input Max Voltage 5.5 Volt

Dropout Voltage 0.240 Volt

Adjustable Output No

Quiescent Current 10 mA

On/Off Pin Yes

Error Flag No

RegType LDO

Temperature Min -40 deg C

Temperature Max 125 deg C

Output Voltage 1.2, 0.8 Volt

Output Max 1.2, 0.8 Volt

PowerWise Yes

Typical Performance

*click for larger image

Also Recommended

LP38852▲	1.5A Adjustable Version
LP38853▲	3A Adjustable Version
LP38859▲	Fixed 0.8V & 1.2V With Soft-start

Additional Resources

Design Tools

Application Notes

Block Diagram

*click for larger image

Block Diagram

Datasheet

RoHS Compliance Information	Size in Kbytes	Date
LP38856 3A Fast-Response High-Accuracy LDO Linear Regulator with Enable	360 Kbytes	10-Mar-07	Download
LP38856 3A Fast-Response High-Accuracy LDO Linear Regulator with Enable (Japanese)	409 Kbytes

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Package Availability, Models, Samples & Pricing

Part Number

Package

Factory Lead Time

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking
Format

Type

Pins

Spec.

MSL
Rating

Peak
Reflow

RoHS
Report

CAD
Symbols

Weeks

Qty

$US each

LP38856-1.2EVAL

3A Fast-Response High-Accuracy LDO Linear Regulator with Enable

Full production

N/A

$30.00

8 weeks

N/A

LP38856T-0.8

TO-220

NOPB

RoHS

Download

Full production

N/A

1K+

$2.00

rail
of
45

NSUZXYTTE#
LP38856T
0.8

6 weeks

500

LP38856T-1.2

TO-220

NOPB

RoHS

Download

Full production

N/A

1K+

$2.00

rail
of
45

NSUZXYTTE#
LP38856T
1.2

6 weeks

500

LP38856S-0.8

TO-263

NOPB

245

RoHS

Download

Full production

N/A

1K+

$2.00

rail
of
45

NSUZXYTTE#
LP38856S
0.8

8 weeks

N/A

LP38856S-1.2

TO-263

NOPB

245

RoHS

Download

Full production

N/A

1K+

$2.00

rail
of
45

NSUZXYTTE#
LP38856S
1.2

6 weeks

500

LP38856SX-0.8

TO-263

NOPB

245

RoHS

Download

Full production

N/A

1K+

$2.00

reel
of
500

NSUZXYTTE#
LP38856S
0.8

6 weeks

N/A

LP38856SX-1.2

TO-263

NOPB

245

RoHS

Download

Full production

N/A

1K+

$2.00

reel
of
500

NSUZXYTTE#
LP38856S
1.2

6 weeks

5000

General Description

The LP38856 is a high-current, fast-response regulator which can maintain output voltage regulation with an extremely low input to output voltage drop. Fabricated on a CMOS process, the device operates from two input voltages: V_BIAS provides power for the internal bias and control circuits, as well as drive for the gate of the N-MOS power transistor, while V_IN supplies power to the load. The use of an external bias rail allows the part to operate from ultra low V_IN voltages. Unlike bipolar regulators, the CMOS architecture consumes extremely low quiescent current at any output load current. The use of an N-MOS power transistor results in wide bandwidth, yet minimum external capacitance is required to maintain loop stability.

The fast transient response of this device makes it suitable for use in powering DSP, Microcontroller Core voltages and Switch Mode Power Supply post regulators. The LP38856 is available in TO-220 and TO-263 5-Lead packages.

Dropout Voltage: 240 mV (typical) at 3A load current.

Low Ground Pin Current: 14 mA (typical) at 3A load current.

Shutdown Current: 1 µA (typical) I_IN(GND) when EN pin is low.

Precision Output Voltage: ±1.0% for T_J = 25°C and ±2.0% for 0°C ≤ T_J ≤ +125°C, across all line and load conditions

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Device Hours	FITS	MTTF (Hours)
LP38856S-0.8	CS065	2	38968	52	4402000	1	1249079519
LP38856S-1.2	CS065	2	38968	52	4402000	1	1249079519
LP38856SX-0.8	CS065	2	38968	52	4402000	1	1249079519
LP38856SX-1.2	CS065	2	38968	52	4402000	1	1249079519
LP38856T-0.8	CS065	2	38968	52	4402000	1	1249079519
LP38856T-1.2	CS065	2	38968	52	4402000	1	1249079519

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.

Design Tools

Title	Size in Kbytes	Date
Article - How to Power Sub-Micron CMOS Loads with an Efficient LDO			View

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Application Notes

Title	Size in Kbytes	Date
AN-1479: Application Note 1479 LP38856S-1.2 Evaluation Board	468 Kbytes	3-Nov-06	Download
AN-1479 (Chinese): Application Note 1479 LP38856S-1.2 Evaluation Board	230 Kbytes

If you have trouble printing or viewing PDF file(s), see Printing Problems.

More Application Notes

Title	Size in Kbytes	Date
AN-1560: Application Note 1560 LP38852MR-ADJ Evaluation Board	280 Kbytes	17-Mar-07	Download
AN-1560 (Chinese): Application Note 1560 LP38852MR-ADJ Evaluation Board	397 Kbytes
AN-1504: Application Note 1504 LP38853S-ADJ Evaluation Board	573 Kbytes	13-Mar-07	Download
AN-1504 (Chinese): Application Note 1504 LP38853S-ADJ Evaluation Board	285 Kbytes
AN-1480: Application Note 1480 LP38859S-1.2 Evaluation Board	522 Kbytes	3-Nov-06	Download
AN-1480 (Chinese): Application Note 1480 LP38859S-1.2 Evaluation Board	228 Kbytes
AN-1815: Application Note 1815 LDOs Ease the Stress of Start-Up	149 Kbytes	23-Sep-08	Download

If you have trouble printing or viewing PDF file(s), see Printing Problems.

[Information as of 8-Nov-2009]