Home Power management Linear & low-dropout (LDO) regulators
Home
Power management
Linear & low-dropout (LDO) regulators

LP3985

ACTIVE

150-mA, low-dropout voltage regulator with bypass & enable

Order now
Data sheet

A newer version of this product is available

open-in-new Compare alternates
Pin-for-pin with same functionality to the compared device
NEW TLV771 ACTIVE 150mA small-size high-PSRR low-dropout (LDO) linear regulator 150-mA, standard-LDO for cost-sensitive applications

LP3985

ACTIVE
Data sheet Order now

Product details

Output options Fixed Output Iout (max) (A) 0.15 Vin (max) (V) 6 Vin (min) (V) 2.5 Vout (max) (V) 5 Vout (min) (V) 2.5 Fixed output options (V) 2.5, 2.6, 2.7, 2.8, 2.85, 2.9, 3, 3.1, 3.2, 3.3, 4.7, 4.75, 4.8, 5 Rating Catalog Noise (µVrms) 30 PSRR at 100 KHz (dB) 42 Iq (typ) (mA) 0.085 Thermal resistance θJA (°C/W) 220 Load capacitance (min) (µF) 1 Regulated outputs (#) 1 Features Enable Accuracy (%) 2 Dropout voltage (Vdo) (typ) (mV) 60 Operating temperature range (°C) -40 to 125
Output options Fixed Output Iout (max) (A) 0.15 Vin (max) (V) 6 Vin (min) (V) 2.5 Vout (max) (V) 5 Vout (min) (V) 2.5 Fixed output options (V) 2.5, 2.6, 2.7, 2.8, 2.85, 2.9, 3, 3.1, 3.2, 3.3, 4.7, 4.75, 4.8, 5 Rating Catalog Noise (µVrms) 30 PSRR at 100 KHz (dB) 42 Iq (typ) (mA) 0.085 Thermal resistance θJA (°C/W) 220 Load capacitance (min) (µF) 1 Regulated outputs (#) 1 Features Enable Accuracy (%) 2 Dropout voltage (Vdo) (typ) (mV) 60 Operating temperature range (°C) -40 to 125
DSBGA (YZR) 5 2.02 mm² 1.616 x 1.25 SOT-23 (DBV) 5 8.12 mm² 2.9 x 2.8
  • Input Voltage: 2.5 V to 6 V
  • 100-mV Maximum Dropout with 150-mA Load
  • 150-mA Verified Output
  • 50-dB PSRR at 1 kHz at VIN = VOUT + 0.2 V
  • ≤ 1.5-µA Quiescent Current when Shut Down
  • Fast Turn-On time: 200 µs (typ.)
  • 30-µVRMS Output Noise (typical) over 10 Hz to 100
    kHz
  • −40°C to 125°C Junction Temperature Range for
    Operation
  • 2.5-V, 2.6-V, 2.7-V, 2.8-V, 2.85-V, 2.9-V, 3-V, 3.1-
    V, 3.2-V, 3.3-V, 4.7-V, 4.75-V, 4.8-V and 5-V
    Outputs Standard
  • Logic Controlled Enable
  • Stable with Ceramic and High-Quality Tantalum
    Capacitors
  • Fast Turnon
  • Thermal Shutdown and Short-Circuit Current Limit
  • Input Voltage: 2.5 V to 6 V
  • 100-mV Maximum Dropout with 150-mA Load
  • 150-mA Verified Output
  • 50-dB PSRR at 1 kHz at VIN = VOUT + 0.2 V
  • ≤ 1.5-µA Quiescent Current when Shut Down
  • Fast Turn-On time: 200 µs (typ.)
  • 30-µVRMS Output Noise (typical) over 10 Hz to 100
    kHz
  • −40°C to 125°C Junction Temperature Range for
    Operation
  • 2.5-V, 2.6-V, 2.7-V, 2.8-V, 2.85-V, 2.9-V, 3-V, 3.1-
    V, 3.2-V, 3.3-V, 4.7-V, 4.75-V, 4.8-V and 5-V
    Outputs Standard
  • Logic Controlled Enable
  • Stable with Ceramic and High-Quality Tantalum
    Capacitors
  • Fast Turnon
  • Thermal Shutdown and Short-Circuit Current Limit

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

The LP3985 is stable with a small 1-µF ±30% ceramic or high-quality tantalum output capacitor. The DSBGA requires the smallest possible PC board area – the total application circuit area can be less than 2 mm × 2.5 mm, a fraction of a 1206 case size.

An optional external bypass capacitor reduces the output noise without slowing down the load transient response. Fast startup 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 1 kHz. 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 2.5-V to 6-V input. The LP3985 consumes less than 1.5 µA in disable mode and has fast turn-on time less than 200 µs.

The LP3985 is available with fixed output voltages from 2.5 V to 5 V. Contact Texas Instruments Sales for specific voltage option needs.

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

The LP3985 is stable with a small 1-µF ±30% ceramic or high-quality tantalum output capacitor. The DSBGA requires the smallest possible PC board area – the total application circuit area can be less than 2 mm × 2.5 mm, a fraction of a 1206 case size.

An optional external bypass capacitor reduces the output noise without slowing down the load transient response. Fast startup 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 1 kHz. 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 2.5-V to 6-V input. The LP3985 consumes less than 1.5 µA in disable mode and has fast turn-on time less than 200 µs.

The LP3985 is available with fixed output voltages from 2.5 V to 5 V. Contact Texas Instruments Sales for specific voltage option needs.
filter Find other Linear & low-dropout (LDO) regulators
Download View video with transcript Video

Similar products you might be interested in

open-in-new Compare alternates
Drop-in replacement with upgraded functionality to the compared device
TPS7A20 ACTIVE 300mA ultra-low-noise low-IQ low-dropout (LDO) linear regulator with high PSRR 300-mA LDO with low-noise (7 uVrms), low-IQ (6.5 uA) with high-PSRR in small package

Technical documentation

star =Top documentation for this product selected by TI
No results found. Please clear your search and try again.
View all 4
Type Title Date
* Data sheet LP3985 Micropower, 150-mA Low-Noise Ultra-Low-Dropout CMOS Voltage Regulator datasheet (Rev. AE) PDF | HTML 08 May 2015
EVM User's guide AN-1219 LP3985 DSBGA-5 Evaluation Board Instruction (Rev. C) 30 Apr 2013
EVM User's guide AN-1223 LP3985 SOT23-5 Evaluation Board (Rev. C) 30 Apr 2013
Application note Understanding Portable Applications Requirements to Improve System Performance 22 Mar 2007

Design & development

For additional terms or required resources, click any title below to view the detail page where available.

Evaluation board

MULTIPKGLDOEVM-823 — Universal LDO linear voltage regulator evaluation module for DBV, DRB, DRV and DQN packages

The MULTIPKGLDOEVM-823 evaluation module (EVM) helps you evaluate the operation and performance of several common packages of linear regulators for possible use in circuit applications. This particular EVM configuration has a DRB, DRV, DQN and DBV footprint for you to solder and (...)

User guide: PDF
Not available on TI.com
Development kit

EVMK2GX — 66AK2Gx 1GHz evaluation module

The EVMK2GX (also known as "K2G") 1GHz evaluation module (EVM) enables developers to immediately start evaluating the 66AK2Gx processor family, and to accelerate the development of audio, industrial motor control, smart grid protection and other high reliability, real-time compute intensive (...)

User guide: PDF
Not available on TI.com
Development kit

EVMK2GXS — 66AK2Gx (K2G) 1GHz High-Secure Evaluation Module

The K2G 1GHz High Secure Evaluation Module (EVM) enables developers to start  evaluating and testing the programming of the  high secure developmental version of the  66AK2Gx processor, and to accelerate the next stage of secure boot product development of audio and industrial real (...)

User guide: PDF
Request
Reference designs

PMP22220 — 1500-W AC switch bridgeless PFC reference design

This reference design is an AC switch bridgeless power factor correction (PFC) that operates with continuous conduction mode (CCM). It takes universal AC-input voltage (90 VAC to 264 VAC), provides 390-V, 1000-W low-line output and 1500-W high-line output. This design uses the UCD3138 digital (...)
Test report: PDF
Schematic: PDF
Reference designs

TIDA-01487 — Isolated CAN Flexible Data (FD) Rate Repeater Reference Design

CAN and CANopen are legacy Fieldbus protocols used in many applications in factory automation. Whenever high voltage can damage the end equipment, there is need for isolation. This isolated CAN flexible data (FD) rate repeater reference design adds electrical isolation between two CAN (...)
Design guide: PDF
Schematic: PDF
Reference designs

PMP20978 — High Efficiency and Power Density 1kW Resonant Converter Reference Design with High Voltage GaN FET

The PMP20978 reference design is a high efficiency, high power density and light weight resonant converter reference design. It converts a 390V input to a 48V/1kW output. The PMP20978 power stage has over 140W/in^3 power density. The whole board weight is less than 230g. With fixed 950kHz (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP21309 — 24-V/500-W resonant converter reference design with HV GaN FET

This reference design is a high-frequency resonant converter reference design. The output voltage is regulated to 24 V with input voltage ranges from 380 V to 400 V using a resonant tank with 500 kHz resonant frequency. A 97.9% peak efficiency is achieved with this design using TI’s (...)
Test report: PDF
Schematic: PDF
Reference designs

PMP21842 — 12-V/500-W resonant converter reference design with HV GaN FET

This high-frequency resonant converter reference design regulates a 12-V output from a 380-V to 400-V input voltage range using a resonant tank with 500 kHz resonant frequency. A peak efficiency of 96.0% (bias supply included) is achieved with this design using our high-voltage GaN device along (...)
Test report: PDF
Schematic: PDF
Package Pins CAD symbols, footprints & 3D models
DSBGA (YZR) 5 Ultra Librarian
SOT-23 (DBV) 5 Ultra Librarian
TI's Standard Terms and Conditions for Evaluation Items apply.

Ordering & quality

Information included:
  • RoHS
  • REACH
  • Device marking
  • Lead finish/Ball material
  • MSL rating/Peak reflow
  • MTBF/FIT estimates
  • Material content
  • Qualification summary
  • Ongoing reliability monitoring
Information included:
  • Fab location
  • Assembly location

Recommended products may have parameters, evaluation modules or reference designs related to this TI product.

Support & training

TI E2E™ forums with technical support from TI engineers

View all forum topics

Content is provided "as is" by TI and community contributors and does not constitute TI specifications. See terms of use.

If you have questions about quality, packaging or ordering TI products, see TI support. ​​​​​​​​​​​​​​

Videos