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ADP121: 150 mA, Low Quiescent Current, CMOS Linear Regulator Data Sheet (Rev. G)8/1/2008PDF979 kB
Alternative Parts
Overview
Features and Benefits
- Input voltage range: 2.3 V to 5.5 V
- Output voltage range: 1.2 V to 3.3 V
- Output current: 150 mA
- Low quiescent current
IGND = 11 μA with 0 μA load
IGND = 30 μA with 150 mA load - Low shutdown current: <1 μA
- Low dropout voltage
90 mV @ 150 mA load - High PSRR
70 dB @ 1 kHz at VOUT = 1.2 V
70 dB @ 10 kHz at VOUT = 1.2 V - Low noise: 40 μV rms at VOUT = 1.2 V
- See data sheet for additional features
Product Details
The ADP121 is a quiescent current, low dropout, linear regulator that operates from 2.3 V to 5.5 V and provides up to 150 mA of output current. The low 135 mV dropout voltage at 150 mA load improves efficiency and allows operation over a wide input voltage range. The low 30 μA of quiescent current at full load makes the ADP121 ideal for battery-operated portable equipment.
The ADP121 is available in output voltages ranging from 1.2 V to 3.3 V. The parts are optimized for stable operation with small 1 μF ceramic output capacitors. The ADP121 delivers good transient performance with minimal board area.
Short-circuit protection and thermal overload protection circuits prevent damage in adverse conditions. The ADP121 is available in a tiny 5-lead TSOT and 4-ball 0.4 mm pitch WLCSP pack-ages and utilizes the smallest footprint solution to meet a variety of portable applications.
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (3)
Documentation & Resources
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AN-1072: How to Successfully Apply Low Dropout Regulators4/27/2010PDF105 kB
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UG-052: RedyKit for the ADP121 LDO3/19/2010PDF118 kB
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FAQs7/26/2017
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Linear Low Dropout (LDO) Regulator Solutions4/17/2018PDF3 M
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CN0405: High Voltage Output DAC with Push-Button Control (Rev. 0)3/14/2017PDF500 K
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CN0280: Robust Completely Isolated Current Sense Circuit with Isolated Power Supply for Solar Photovoltaic Converters10/11/2013PDF468 kB
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CN-0185: A Novel Analog-to-Analog Isolator Using an Isolated Sigma-Delta Modulator, Isolated DC-to-DC Converter, and Active Filter10/1/2013PDF119 kB
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CN-0190: Robust, Multivoltage, High Efficiency, 25 W Universal Power Supply Module with 6 V to 14 V Input9/20/2011PDF357 kB
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CN-0187: Crest Factor, Peak, and RMS RF Power Measurement Circuit Optimized for High Speed, Low Power, and Single 3.3 V Supply7/26/2011PDF163 kB
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CN-0164: Low Power, Long Range, ISM Wireless Measuring Node11/30/2010PDF172 kB
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Power Management for Integrated RF ICs1/1/2015 Analog Dialogue
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How to Successfully Apply Low-Dropout Regulators9/1/2009 Analog Dialogue
Tools & Simulations
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Models for the following parts are available in LTspice:
Design Tools
Microsoft Excel download tool from ADIsimPower to generate a power supply design complete with a schematic, bill of materials, and performance specifications.
Reference Designs (6)
Design Resources
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PCN-PDN Information
Sample & Buy
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Evaluation Boards
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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.