LP3985 - Micropower, 150mA Low-Noise Ultra Low-Dropout CMOS Voltage Regulator
Datasheet Packaging Samples & Pricing Reliability Application Notes Knowledge Base

Features
•Miniature 5-I/O micro SMD and SOT-23-5 package
•Logic controlled enable
•Stable with ceramic and high quality tantalum capacitors
•Fast turn-on
•Thermal shutdown and short-circuit current limit

Key Specification

•2.5 to 6.0V input range
•150mA guaranteed output
•50dB PSRR at 1kHz @ VIN = VOUT + 0.2V
•<=1.5µA quiescent current when shut down
•Fast Turn-On time: 200 µs (typ.)
•100mV maximum dropout with 150mA load
•30µVrms output noise (typ) over 10Hz to 100kHz
•-40 to +125°C junction temperature range for operation
•2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V, 3.1V, 3.2V, 3.3V, 4.7V, 4.75V, 4.8V and 5.0V outputs standard

General Description

The LP3985 is designed for portable and wireless applications with demanding performance and space requirements.

The LP3985 is stable with a small 1µF ±30% ceramic or high-quality tantalum output capacitor. More...


Applications

•CDMA cellular handsets
•Wideband CDMA cellular handsets
•GSM cellular handsets
•Portable information appliances
  Typical Application
click for larger image


ParametersValues
Output Current 150 mA
Output Min 2.6, 4.7, 2.7, 2.5, 3.2, 3.3, 3, 2.8, 2.9, 3.1, 5 Volt
Input Min Voltage 2.5 Volt
Input Max Voltage 6 Volt
Dropout Voltage 0.06 Volt
Adjustable Output No
Quiescent Current 0.085 mA
PSRR 50 dB
Voltage Noise (rms) 30 uV
On/Off Pin Yes
Error Flag No
RegType LDO
Temperature Min -40 deg C
Temperature Max 125 deg C
Output Voltage 2.6, 4.7, 2.7, 2.5, 3.2, 3.3, 3, 2.8, 2.9, 3.1, 5 Volt
Output Max 2.6, 4.7, 2.7, 2.5, 3.2, 3.3, 3, 2.8, 2.9, 3.1, 5 Volt


Typical Performance

click for larger image


  Also Recommended
LP3986Dual 150mA Output Version
LP3987▲LP3985 W/ Sleep Mode
LP3988▲LP3985 W/ Power Good Flag
LP3995▲25uV Noise, 60dB PSRR
LP3996Dual 150mA
LP5900▲Wide Selection Of Voltage Options, Supports Ceramic Capacitors
LP2983▲0.9V, 1.0V And 1.2V Output Options
LP3981▲300mA Version
Additional Resources
Online Seminars Application Notes


Block Diagram

click for larger image



Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LP3985 Micropower, 150mA Low-Noise Ultra Low-Dropout CMOS Voltage Regulator 993
Kbytes		 23-Aug-05 Download
LP3985 Micropower, 150mA Low-Noise Ultra Low-Dropout CMOS Voltage Regulator (Japanese)
 854 Kbytes   Download

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


Package Availability, Models, Samples & Pricing
Part NumberPackageFactory Lead TimeModelsSamples &
Electronic
Orders		Budgetary PricingStd
Pack
Size		Package
Marking
Format
TypePinsSpec.MSL
Rating		Peak
Reflow		RoHS
Report		CAD
Symbols		WeeksQtyQty$US each
LP3985IM5-285SOT-235NOPB1260RoHS Download Lifetime buyN/A
 
Buy Now 		1K+$0.29reel
of
1000		LCXB
XTT
12 weeks7500
LP3985IM5-3.1SOT-235NOPB1260RoHS Download Lifetime buyN/A
 
Buy Now 		1K+$0.29reel
of
1000		LCZB
XTT
12 weeks5000
LP3985IM5-2.5SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LCSB
XTT
12 weeks7500
LP3985IM5-2.7SOT-235NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
1000		LCUB
XTT
12 weeks5000
LP3985IM5-2.8SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LCJB
XTT
8 weeks15000
LP3985IM5-2.9SOT-235NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
1000		LCYB
XTT
12 weeks5000
LP3985IM5-3.0SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LCRB
XTT
6 weeks15000
LP3985IM5-3.2SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
1000		LDPB
XTT
12 weeks7500
LP3985IM5-3.3SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LDQB
XTT
6 weeks5000
LP3985IM5-4.7SOT-235NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LDRB
XTT
6 weeks5000
LP3985IM5-5.0SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.29reel
of
1000		LDSB
XTT
12 weeks15000
LP3985IM5X-2.6SOT-235NOPB1260RoHS Download Lifetime buyN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCTB
XTT
12 weeks7500
LP3985IM5X-2.9SOT-235NOPB1260RoHS Download Lifetime buyN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCYB
XTT
6 weeksN/A
LP3985IM5X-3.2SOT-235NOPB1260RoHS Download Lifetime buyN/A
 
Buy Now 		1K+$0.29reel
of
3000		LDPB
XTT
6 weeks7500
LP3985IM5X-2.5SOT-235NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCSB
XTT
6 weeks5000
LP3985IM5X-2.8SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCJB
XTT
6 weeks7500
LP3985IM5X-285SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCXB
XTT
6 weeks40000
LP3985IM5X-3.0SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LCRB
XTT
6 weeks10000
LP3985IM5X-3.3SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LDQB
XTT
6 weeks10000
LP3985IM5X-4.7SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LDRB
XTT
6 weeks7500
LP3985IM5X-5.0SOT-235NOPB
STD		1
1		260
260		RoHS Download Full productionN/A
 
Buy Now 		1K+$0.29reel
of
3000		LDSB
XTT
6 weeks20000
LP3985ITL-2.5MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
12 weeksN/A
LP3985ITL-2.6MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
6 weeksN/A
LP3985ITL-2.7MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
6 weeksN/A
LP3985ITL-2.8MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
6 weeksN/A
LP3985ITL-2.9MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
6 weeksN/A
LP3985ITL-285MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
6 weeksN/A
LP3985ITL-3.0MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
16 weeksN/A
LP3985ITL-3.1MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
16 weeksN/A
LP3985ITL-3.2MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
16 weeksN/A
LP3985ITL-3.3MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
12 weeksN/A
LP3985ITL-4.75MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
16 weeksN/A
LP3985ITL-4.8MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
250		XV
I 5
12 weeksN/A
LP3985ITL-5.0MICRO SMD5NOPB1260RoHS Download Full productionN/A
Samples
Buy Now 		1K+$0.32reel
of
250		XV
I 5
12 weeksN/A
LP3985ITLX-2.5MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
12 weeksN/A
LP3985ITLX-2.6MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
8 weeksN/A
LP3985ITLX-2.7MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
8 weeksN/A
LP3985ITLX-2.8MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
6 weeksN/A
LP3985ITLX-2.9MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
8 weeksN/A
LP3985ITLX-285MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
6 weeksN/A
LP3985ITLX-3.0MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
6 weeksN/A
LP3985ITLX-3.1MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
12 weeksN/A
LP3985ITLX-3.2MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
12 weeksN/A
LP3985ITLX-3.3MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
6 weeksN/A
LP3985ITLX-4.75MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
16 weeksN/A
LP3985ITLX-4.8MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
16 weeksN/A
LP3985ITLX-5.0MICRO SMD5NOPB1260RoHS Download Full productionN/A
 
Buy Now 		1K+$0.32reel
of
3000		XV
I 5
12 weeksN/A

Obsolete Versions

Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
LP3985IBL-285
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBL-2.5
LP3985ITL-2.5
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-2.6
LP3985ITL-2.6
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-2.7
LP3985ITL-2.7
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-2.8
LP3985ITL-2.8
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-2.9
LP3985ITL-2.9
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-3.0
LP3985ITL-3.0
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-3.1
LP3985ITL-3.1
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-3.2
LP3985ITL-3.2
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-3.3
LP3985ITL-3.3
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-4.8
LP3985ITL-4.8
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBL-5.0
LP3985ITL-5.0
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-285
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBLX-2.5
LP3985ITLX-2.5
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-2.6
LP3985ITLX-2.6
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-2.7
LP3985ITLX-2.7
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-2.8
LP3985ITLX-2.8
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-2.9
LP3985ITLX-2.9
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-3.0
LP3985ITLX-3.0
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-3.1
LP3985ITLX-3.1
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-3.2
LP3985ITLX-3.2
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-3.3
LP3985ITLX-3.3
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-4.8
LP3985ITLX-4.8
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBLX-5.0
LP3985ITLX-5.0
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBP-285
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBP-2.5
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBP-2.7
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBP-2.8
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBP-2.9
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBP-3.0
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBP-3.2
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBP-3.3
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBP-5.0
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBPX-2.5
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBPX-2.7
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBPX-2.8
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBPX-2.9
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBPX-3.0
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IBPX-3.1
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IBPX-3.3
NONE
NATIONAL SEMICONDUCTOR
24 Jul 2009
LP3985IM5-285
NONE
NATIONAL SEMICONDUCTOR
01 Dec 2009
LP3985IM5-2.6
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IM5-3.1
NONE
NATIONAL SEMICONDUCTOR
01 Dec 2009
LP3985IM5X-2.6
NONE
NATIONAL SEMICONDUCTOR
01 Dec 2009
LP3985IM5X-2.7
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IM5X-2.9
NONE
NATIONAL SEMICONDUCTOR
01 Dec 2009
LP3985IM5X-3.1
NONE
NATIONAL SEMICONDUCTOR
16 Nov 2008
LP3985IM5X-3.2
NONE
NATIONAL SEMICONDUCTOR
01 Dec 2009

General Description

The LP3985 is designed for portable and wireless applications with demanding performance and space requirements.

The LP3985 is stable with a small 1µF ±30% ceramic or high-quality tantalum output capacitor. The micro SMD requires the smallest possible PC board area - the total application circuit area can be less than 2.0mm x 2.5mm, a fraction of a 1206 case size.

The LP3985's performance is optimized for battery powered systems to deliver ultra low noise, extremely low dropout voltage and low quiescent current. Regulator ground current increases only slightly in dropout, further prolonging the battery life.

An optional external bypass capacitor reduces the output noise without slowing down the load transient response. Fast start-up time is achieved by utilizing an internal power-on circuit that actively pre-charges the bypass capacitor.

Power supply rejection is better than 50 dB at low frequencies and starts to roll off at 1kHz. High power supply rejection is maintained down to low input voltage levels common to battery operated circuits.

The device is ideal for mobile phone and similar battery powered wireless applications. It provides up to 150 mA, from a 2.5V to 6V input. The LP3985 consumes less than 1.5µA in disable mode and has fast turn-on time less than 200µs.

The LP3985 is available in a 5 bump small bump micro SMD, a 5 bump large bump micro SMD, a 5 bump thin micro SMD and a 5 pin SOT-23 package. Performance is specified for -40°C to +125°C temperature range and is available in 2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V. 3.1V, 3.2V, 3.3V, 4.7V, 4.75V, 4.8V and 5.0V output voltages. For other output voltage options between 2.5V to 5.0V or for a dual LP3985, please contact National Semiconductor sales office.

Reliability Metrics

Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
LP3985IM5-2.5CMOS70184060010890004309006723
LP3985IM5-2.6CMOS70184060010890004309006723
LP3985IM5-2.7CMOS70184060010890004309006723
LP3985IM5-2.8CMOS70184060010890004309006723
LP3985IM5-2.9CMOS70184060010890004309006723
LP3985IM5-285CMOS70184060010890004309006723
LP3985IM5-3.0CMOS70184060010890004309006723
LP3985IM5-3.1CMOS70184060010890004309006723
LP3985IM5-3.2CMOS70184060010890004309006723
LP3985IM5-3.3CMOS70184060010890004309006723
LP3985IM5-4.7CMOS70184060010890004309006723
LP3985IM5-5.0CMOS70184060010890004309006723
LP3985IM5X-2.5CMOS70184060010890004309006723
LP3985IM5X-2.6CMOS70184060010890004309006723
LP3985IM5X-2.7CMOS70184060010890004309006723
LP3985IM5X-2.8CMOS70184060010890004309006723
LP3985IM5X-2.9CMOS70184060010890004309006723
LP3985IM5X-285CMOS70184060010890004309006723
LP3985IM5X-3.0CMOS70184060010890004309006723
LP3985IM5X-3.1CMOS70184060010890004309006723
LP3985IM5X-3.2CMOS70184060010890004309006723
LP3985IM5X-3.3CMOS70184060010890004309006723
LP3985IM5X-4.7CMOS70184060010890004309006723
LP3985IM5X-5.0CMOS70184060010890004309006723
LP3985ITL-2.5CMOS70184060010890004309006723
LP3985ITL-2.6CMOS70184060010890004309006723
LP3985ITL-2.7CMOS70184060010890004309006723
LP3985ITL-2.8CMOS70184060010890004309006723
LP3985ITL-2.9CMOS70184060010890004309006723
LP3985ITL-285CMOS70184060010890004309006723
LP3985ITL-3.0CMOS70184060010890004309006723
LP3985ITL-3.1CMOS70184060010890004309006723
LP3985ITL-3.2CMOS70184060010890004309006723
LP3985ITL-3.3CMOS70184060010890004309006723
LP3985ITL-4.75CMOS70184060010890004309006723
LP3985ITL-4.8CMOS70184060010890004309006723
LP3985ITL-5.0CMOS70184060010890004309006723
LP3985ITLX-2.5CMOS70184060010890004309006723
LP3985ITLX-2.6CMOS70184060010890004309006723
LP3985ITLX-2.7CMOS70184060010890004309006723
LP3985ITLX-2.8CMOS70184060010890004309006723
LP3985ITLX-2.9CMOS70184060010890004309006723
LP3985ITLX-285CMOS70184060010890004309006723
LP3985ITLX-3.0CMOS70184060010890004309006723
LP3985ITLX-3.1CMOS70184060010890004309006723
LP3985ITLX-3.2CMOS70184060010890004309006723
LP3985ITLX-3.3CMOS70184060010890004309006723
LP3985ITLX-4.75CMOS70184060010890004309006723
LP3985ITLX-4.8CMOS70184060010890004309006723
LP3985ITLX-5.0CMOS70184060010890004309006723

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.


Application Notes

TitleSize in Kbytes Date Click link below to Download
AN-1223: Application Note 1228 LP3986 microSMD Evaluation Board Instruction 29
Kbytes		 14-May-04 Download
AN-1219: Application Note 1219 LP3985 MicroSMD‐5 Evaluation Board Instruction 36
Kbytes		 10-May-04 Download

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

More Application Notes

TitleSize in Kbytes Date Click link below to Download
AN-1228: Application Note 1228 LP3986 microSMD Evaluation Board Instruction 29
Kbytes		 14-May-04 Download

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

[Information as of 8-Nov-2009]