Diodes Incorporated AP7351D-12FS4-7B

Overview

AP7351D-12FS4-7B from Diodes Incorporated is a 150mA ultra-low quiescent current LDO regulator with fixed 1.2V output, ±1% accuracy at +25°C, 0.5µA quiescent current, and X2-DFN1010-4 (Type B) package. It integrates enable control, active output discharge, and operates from 1.4V to 5.5V input, targeting power management in wearable electronics and IoT sensor modules.

For engineers reviewing the AP7351D-12FS4-7B datasheet, AP7351D-12FS4-7B pinout, AP7351D-12FS4-7B application, or AP7351D-12FS4-7B equivalent, key selection criteria include dropout voltage at 150mA (0.8V typ. for 1.2V VOUT), standby current (0.02µA), EN logic thresholds (0.4V low / 1.0V high), and thermal resistance (237°C/W).

Technical Context

The AP7351D-12FS4-7B implements a PMOS pass transistor architecture enabling ultra-low quiescent current and fast enable turn-on response (typ. 40µs). Its internal voltage reference and error amplifier maintain ±1% output accuracy across -40°C to +85°C ambient temperature.

It features active output discharge via integrated 35Ω pull-down resistor when EN is low, ensuring rapid VOUT decay. The device supports stable operation with 0.1µF ceramic input/output capacitors and exhibits 60dB PSRR at 1kHz under 20mA load.

Key Specifications

Pinout & Package

X2-DFN1010-4 (Type B) package: 1.0mm × 1.0mm, 0.4mm pitch, exposed thermal pad (EP), moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with MCP1700-1202E/TO and TPS7A0212PDBVR, the AP7351D-12FS4-7B uniquely balances ultra-low IQ (0.5µA), active discharge, and minimal 1.0mm² footprint - making it optimal for space- and energy-constrained wearables where rapid, controlled power sequencing is essential.

Availability

AP7351D-12FS4-7B is available at Aetrix Electronics and suitable for wearable electronics, IoT sensor nodes, medical edge devices, and miniature camera modules requiring stable component supply with guaranteed long-term availability.

Supply support for AP7351D-12FS4-7B includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal ICs, with design centers across Asia, Europe, and the US.

The AP7351D belongs to Diodes' ultra-low-IQ LDO family, engineered specifically for extended battery life in portable and energy-sensitive applications such as wearables and wireless sensors.

FAQ

What is the minimum input voltage required for AP7351D-12FS4-7B to regulate 1.2V output at 150mA?

The minimum input voltage is determined by dropout: at 150mA, typical dropout is 0.8V, so VIN must be ≥ 2.0V (1.2V + 0.8V) to sustain regulation. Absolute minimum VIN per spec is 1.4V, but regulation fails below 2.0V under full load.

Does AP7351D-12FS4-7B require an external discharge resistor?

No. The device integrates a 35Ω active discharge FET between VOUT and GND, activated automatically when EN is pulled low. This eliminates the need for external components while ensuring VOUT decays rapidly (typically <1ms) after shutdown.

Can AP7351D-12FS4-7B operate with ceramic capacitors smaller than 0.1µF?

No. The datasheet specifies stability with ≥0.1µF X5R/X7R ceramic capacitors on both input and output. Using smaller values risks instability and oscillation due to insufficient phase margin, especially under transient load conditions.

Is the exposed pad (EP) of the X2-DFN1010-4 package electrically connected to GND?

No. The EP is not internally connected to any pin. It serves solely as a thermal path and should be soldered to a PCB copper pour tied to GND for heat dissipation - but must not be used as the sole GND connection for the device's electrical reference.