LP3985

ACTIVE

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

A newer version of this product is available

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NEW TLV771 ACTIVE 150mA small-size high-PSRR low-dropout (LDO) linear regulator 150-mA, standard-LDO for cost-sensitive applications

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.

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Technical documentation

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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

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Package Pins CAD symbols, footprints & 3D models
DSBGA (YZR) 5 Ultra Librarian
SOT-23 (DBV) 5 Ultra Librarian

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