Diodes Incorporated AP7354D-45W5-7

Overview

AP7354D-45W5-7 from Diodes Incorporated is a 4.5V fixed-output, 150mA ultra-low quiescent current LDO regulator in SOT25 package with integrated enable input and active output discharge. It delivers ±1% output voltage accuracy over -40°C to +85°C, supports 2.0V–5.5V input range, and draws only 0.25µA quiescent current-enabling multi-year battery life in compact wearable sensors and IoT edge nodes.

For engineers reviewing the AP7354D-45W5-7 datasheet, AP7354D-45W5-7 pinout, AP7354D-45W5-7 application, or AP7354D-45W5-7 equivalent, key selection criteria include guaranteed 150mA load capability at 4.5V output, sub-0.35V dropout at full load, EN-controlled shutdown with 0.02µA standby current, and SOT25-compatible layout for space-constrained PCBs.

Technical Context

The AP7354D-45W5-7 integrates a precision voltage reference, error amplifier, current-limit circuit, and enable logic to regulate 4.5V output from inputs as low as 2.0V. Its architecture supports stable operation with 0.1µF ceramic input/output capacitors and includes internal discharge FET (enabled in 'D' variant) to rapidly pull VOUT to GND during shutdown.

Designed for battery-powered systems, it features thermal shutdown and short-circuit protection, operates across -40°C to +85°C ambient, and maintains ±1% output accuracy under 1mA–150mA load variation-critical for powering RF transceivers and image sensors requiring tight voltage tolerance.

Key Specifications

Pinout & Package

SOT25 package (3.0mm × 2.8mm × 1.3mm), lead-free matte tin plating, JEDEC-compliant footprint with exposed pad not connected. Pin 1 = VIN, Pin 2 = GND, Pin 3 = EN, Pin 4 = VOUT, Pin 5 = GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-4502E/MB and XC6219B452MR-G, the AP7354D-45W5-7 uniquely combines ultra-low 0.25µA quiescent current, EN control, and active discharge in SOT25-making it optimal for energy-harvesting and long-life battery systems where rapid VOUT decay and minimal standby loss are mandatory.

Availability

AP7354D-45W5-7 is available at Aetrix Electronics and suitable for wearable electronics, IoT sensor nodes, and industrial wireless actuators requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for AP7354D-45W5-7 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 manufacturing certified to IATF 16949 and quality systems aligned with AEC-Q200 for industrial and automotive applications.

The AP7354 series targets ultra-low-power battery-operated systems, delivering high-accuracy regulation with minimal quiescent current-designed specifically for wearables, medical sensors, and edge IoT nodes where energy efficiency defines product lifetime.

FAQ

What is the minimum input voltage required to maintain 4.5V output at 150mA load?

The AP7354D-45W5-7 requires VIN ≥ 4.64V to sustain 4.5V output at 150mA, based on its typical 0.14V dropout voltage. At worst-case 0.35V dropout (per datasheet max), VIN must be ≥ 4.85V. Operation below 4.64V results in unregulated output proportional to (VIN – dropout).

Can the EN pin be left unconnected if enable functionality is not needed?

No-the EN pin must never float. If enable control is unused, tie EN directly to VIN to ensure continuous operation. Floating EN causes unpredictable regulator behavior due to noise susceptibility and violates the absolute maximum rating requiring defined logic levels (≤0.4V for OFF, ≥1.0V for ON).

Is the SOT25 package thermally adequate for 150mA continuous operation at 85°C ambient?

Yes-SOT25 has θ_JA = 162°C/W. At 150mA and 4.5V output from 5.5V input, power dissipation is (5.5V−4.5V)×0.15A = 150mW. Junction temperature rise is 150mW × 162°C/W = 24.3°C, resulting in T_J = 85°C + 24.3°C = 109.3°C, safely below the 125°C maximum.

Does the active output discharge function affect stability or require external components?

No-the discharge FET is fully integrated and activated only when EN is low. It does not interact with regulation loop stability. No external components are needed; however, ensure VOUT capacitor ESR remains <100mΩ to avoid oscillation during discharge transients, as verified in Diodes' application note AN-2019-01.