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The AP3503 is a 340kHz fixed frequency, current mode, PWM synchronous buck (step-down) DC-DC converter, capable of driving a 3A load with high efficiency, excellent line and load regulation. The device integrates N-channel power MOSFET switches with low on-resistance. Current mode control provides fast transient response and cycle-by-cycle current limit. The AP3503 employs complete protection to ensure system security. Including output Over Voltage Protection, input Under Voltage LockOut, programmable soft-start, Over Temperature Protection to safeguard the circuit. This IC is available in PSOP-8 package.


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Product Specifications

Product Parameters

Type Buck
Efficiency (%) 95 %
HS RDS(ON) (mΩ) 100 mΩ
LS RDS(ON) (mΩ) 100 mΩ
Frequency Typ (Hz) 340 kHz
MinimumInput Voltage (V) 4.5 V
MaximumInput Voltage (V) 18 V
Output Current (A) 3 A
Output Voltage (V) ADJ V
Quiescent Current Typ (mA) 1.2 mA
Shutdown Current Typ (µA) 0.1 µA

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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-2555 2021-11-11 2022-05-11 Device End of Life (EOL)
PCN-2427 2019-10-15 2020-04-15 Device End of Life (EOL)