Diodes Incorporated AP7375-18Y-13

Overview

AP7375-18Y-13 from Diodes Incorporated is a 1.8V fixed-output, wide-input (3–45V), 300mA ultra-low-dropout linear regulator in SOT89 package with 2.1μA quiescent current, 35mV dropout at 10mA, and integrated enable pin rated to 45V - designed for battery-powered smoke detectors requiring stable low-power rail generation under wide input transients.

For engineers reviewing the AP7375-18Y-13 datasheet, AP7375-18Y-13 pinout, AP7375-18Y-13 application, or AP7375-18Y-13 equivalent, this page delivers verified electrical specs, thermal performance data, SOT89 pin mapping, real-world transient response behavior, and validated alternative LDOs for industrial sensor and microcontroller power domains.

Technical Context

The AP7375-18Y-13 implements a PMOS pass transistor architecture enabling 35mV dropout at light load and 350mV at 100mA, with internal compensation ensuring stability with 1–10μF ceramic output capacitors. Its EN pin accepts up to 45V directly, eliminating level-shifting circuitry in high-voltage enable paths.

It features fast line/load transient response (undershoot/overshoot suppressed per startup and short-circuit recovery), ±2% output voltage accuracy over -40°C to +125°C junction temperature, and dual protection: thermal shutdown at +150°C with +20°C hysteresis and current limiting at 500mA.

Key Specifications

Pinout & Package

SOT89-3 (Package Code: Y) package with exposed pad (EP) for enhanced thermal dissipation; recommended PCB layout uses ≥25 mm² copper area connected to GND under EP.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-low-IQ, wide-VIN LDO applications.

Compared with AP7375-18Y-13, AP7361-18Y-13 trades 150mA output headroom for identical footprint and cost, while TPS7A16A-18DRBR offers lower IQ but demands layout revision and sacrifices current capability - making AP7375-18Y-13 optimal for 300mA, SOT89-constrained designs needing balanced performance.

Availability

AP7375-18Y-13 is available at Aetrix Electronics and suitable for battery-powered equipment, smoke detectors and sensors, microcontroller applications, and home appliances requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for AP7375-18Y-13 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 solutions, with design centers in Asia, Europe, and the U.S., serving industrial, computing, consumer, and automotive markets.

The AP7375 series belongs to Diodes' high-reliability LDO portfolio targeting wide-input, ultra-low-power applications - engineered specifically for battery longevity, transient robustness, and simplified enable control in safety-critical sensing systems.

FAQ

What is the minimum input voltage required for AP7375-18Y-13 to regulate 1.8V output?

The AP7375-18Y-13 requires VIN ≥ VOUT + VDROP(MAX). At 100mA load, VDROP is 360mV max, so minimum VIN is 2.16V. However, the datasheet specifies 3.0V as absolute minimum operating input due to internal biasing constraints - below 3V, regulation is not guaranteed even if dropout voltage appears sufficient.

Can the EN pin be left floating, or does it require a pull-up/down resistor?

The EN pin must not be left floating. It has no internal pull-up/down; floating state causes undefined output behavior. For always-on operation, connect EN directly to VIN. For controlled enable, use a resistor divider or direct GPIO drive - EN threshold is 1V (min) for high, 0.4V (max) for low, with 45V absolute max rating.

Is the exposed pad (EP) on the SOT89 package electrically connected internally?

No - the exposed pad is thermally conductive only and not electrically tied to any internal node. It must be soldered to a GND-connected copper pour for thermal performance, but should never be used as the sole GND connection point; the dedicated Pin 2 (GND) remains the primary signal ground return path.

Does AP7375-18Y-13 require an input capacitor, and what type is recommended?

Yes - a 1μF ceramic capacitor (X7R or X5R dielectric) is mandatory between VIN and GND, placed within 3mm of the pins. This stabilizes input impedance, suppresses high-frequency noise, and prevents oscillation during fast load transients; larger values improve immunity but are not required for basic functionality.