Diodes Incorporated AP7387-33Y-13

Overview

AP7387-33Y-13 from Diodes Incorporated is a 3.3V fixed-output, wide-input (5–60V), 150mA ultra-low-dropout linear regulator in SOT89 package with 700mV dropout at 100mA, 2μA quiescent current, and 70dB PSRR at 1kHz-designed for battery-powered smoke detectors and EV battery management systems where high input voltage tolerance and low standby power are critical.

For engineers reviewing the AP7387-33Y-13 datasheet, AP7387-33Y-13 pinout, AP7387-33Y-13 application, or AP7387-33Y-13 equivalent, key selection criteria include dropout voltage under load, thermal resistance (165°C/W for SOT89), output accuracy (±2%), transient response performance, and compatibility with 10μF ceramic output capacitance.

Technical Context

The AP7387-33Y-13 integrates a precision voltage reference, error amplifier, and current-limit circuit with thermal shutdown and short-circuit protection. Its architecture delivers fast line/load transient response due to optimized internal compensation and low-output-impedance regulation.

It operates across –40°C to +85°C ambient temperature with junction limit of +125°C, supports 1μF input and 10μF output ceramic capacitors (X7R/X5R), and maintains ±2% output accuracy over full load and input voltage range (5–60V).

Key Specifications

Pinout & Package

SOT89 package (AP7387-33Y-13) features 3 pins in standard configuration: Pin 1 = VIN, Pin 2 = GND, Pin 3 = VOUT. The exposed tab is internally connected to GND and must be soldered to a large copper pour for thermal dissipation (θJA = 165°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP7387-33Y-13, AP7361-33Y-13 trades 20V input headroom for lower cost, while TPS7B8733QKVURQ1 adds automotive qualification and diagnostics at expense of reduced input range and higher price-making AP7387-33Y-13 optimal for industrial and consumer 48–60V applications needing maximum voltage margin and minimal IQ.

Availability

AP7387-33Y-13 is available at Aetrix Electronics and suitable for battery-powered equipment, smoke detectors and sensors, and EV/HEV battery management systems requiring stable component supply across extended temperature and voltage ranges.

Supply support for AP7387-33Y-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 devices for industrial, automotive, computing, and consumer markets.

The AP7387 belongs to Diodes' ultra-low-IQ, wide-input LDO family engineered for battery longevity and high-voltage resilience in safety-critical and energy-constrained applications.

FAQ

What is the minimum input voltage required for regulation at 3.3V output?

The AP7387-33Y-13 requires VIN ≥ VOUT + VDROP. With typical dropout of 700mV at 100mA, minimum input is 4.0V. At full 150mA load, dropout rises to 1100mV, so VIN must be ≥4.4V to maintain regulation. Input below 5V is not recommended per absolute maximum ratings.

Can AP7387-33Y-13 replace AP7387-33SA-7 in an existing SOT23 design?

No-AP7387-33Y-13 uses SOT89 package (larger footprint, higher thermal mass, θJA = 165°C/W), while AP7387-33SA-7 uses SOT23 (θJA = 248.5°C/W). Direct replacement requires PCB pad redesign, thermal validation, and requalification of transient response due to different parasitic inductance and capacitance.

Is an external bypass capacitor required on the VREF or ADJ pin?

No-AP7387-33Y-13 is a fixed-output LDO with no adjustable feedback pins. It has no VREF or ADJ terminal; only VIN, GND, and VOUT pins exist. The internal voltage reference is trimmed and stabilized; no external capacitor is needed or supported.

Does AP7387-33Y-13 support reverse-polarity input protection?

No-the device lacks integrated reverse-voltage protection. Applying negative voltage to VIN relative to GND violates Absolute Maximum Rating (–0.3V), risking permanent damage. External series diode or MOSFET-based protection must be added if reverse polarity is possible in the system.