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250MA Ultra Low Quiescent Current CMOS LDO

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The AP2138/2139 series are CMOS-based positive voltage regulator ICs. Each of these ICs consists of a voltage reference, an error amplifier, a resistor network for setting output voltage and a current limit circuit for current protection. The difference between AP2138 and AP2139 is the AP2139 has an enable circuit with a quick discharge function. These ICs feature high output voltage accuracy, extremely low quiescent current and low dropout voltage which make them ideal for use in various power sources for portable applications. The AP2138/2139 series have 1.2V, 1.4V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V, 3.3V, 3.6V and 4.0V fixed output voltage versions.


· Ultra-low Quiescent Current: 1.0μA Typical · Output Voltages: 1.2V, 1.4V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V, 3.3V, 3.6V and 4.0V · High Output Voltage Accuracy: ±2% · Output Current: 250mA · Low Dropout Voltage: - 25mV Typical at IOUT=10mA and VOUT=3V - 200mV Typical at IOUT=100mA and VOUT=3V · Line Regulation: 6mV Typical · Load Regulation: 25mV Typical · Low Output Voltage Temperature Coefficient: ±100ppm/C · Low Standby Current: 0.1μA Typical (AP2139) · Active Quick Output Discharge (AP2139) · Logic-control°C Enable (AP2139)


· Battery Powered Equipment · Reference Voltage Sources · Cameras, Video Cameras · Portable AV Systems · Mobile Phones · Communication Tools · Portable Games

Product Specifications

Product Parameters

Compliance (Only Automotive supports PPAP) Standard
Output options Fixed
Iout (A) 0.25
Vin (Max) (V) 6
Vin (Min) (V) 2.5
Vout (min) 1.2
Vout (max) 4
Fixed Vout (V) 1.2, 1.4, 1.5, 1.8, 2.1, 2.5, 2.8, 3.0, 3.3, 3.6, 4.0
Iq (typ) (µA) 1
Accuracy 25C 2%
VDROPOUT (Max) (V) at Max Current and Max Ouput Voltage 0.6
PSRR (dB) 1kHz 55
Operating Temperature (Ambient) (°C) -40 to 85 (°C)
Enable Active H
Channels 1
Output Discharge yes
Iq (max)(µA) 1.5
VCTL function no

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Product Change Notices (PCNs)

A PCN may only apply to specific orderable part numbers in this datasheet. Please refer to the corresponding PCN to see the exact orderable part number(s) affected.

PCN # Issue Date Implementation Date Subject
PCN-2343 2018-05-15 2018-08-15 Qualification of Additional Bill of Materials (BOM), Fab Source for Select Products with Top Marking Change on Select Product