Asahi Kasei Microdevices/AKM AP1152ADU18

Overview

AP1152ADU18 from Diodes Incorporated is a 1.8 V, 300 mA low-dropout linear regulator with high-accuracy output voltage (±1.5% or ±50 mV), 105 mV dropout at 100 mA, and integrated on/off control (high-active). It operates from 2.1 V to 14.5 V input and supports ultra-low-noise applications using a 0.1 µF ceramic output capacitor - commonly deployed in RF power supplies and precision analog signal chains.

For engineers reviewing the AP1152ADU18 datasheet, AP1152ADU18 pinout, AP1152ADU18 application, or AP1152ADU18 equivalent, this page delivers verified technical context, package-specific pin functions, real-world application mappings, and two validated alternative parts for low-noise LDO selection in automotive infotainment, image sensor biasing, and post-regulation of switching supplies.

Technical Context

The AP1152ADU18 implements a bandgap-referenced NPN pass transistor architecture with internal current limiting and thermal shutdown. Its noise-bypass terminal (NP) enables configurable ripple rejection-80 dB at 1 kHz-with external capacitor tuning, while the built-in 500 kΩ pull-down resistor on VCONT simplifies CMOS-level on/off control without external biasing.

Stability is ensured with ≥0.1 µF ceramic output capacitance (for VOUT ≥ 2.5 V), and the SOT89-5 package provides 138°C/W junction-to-ambient thermal resistance on a 4-layer JEDEC51-3 board. The device maintains regulation across –40°C to +85°C ambient, with load regulation ≤24 mV (IOUT = 5–100 mA) and line regulation ≤8 mV.

Key Specifications

Pinout & Package

SOT89-5 package: 5-pin surface-mount plastic package with exposed pad not present; thermal performance rated at θ_JA = 138°C/W on 4-layer JEDEC51-3 board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP1152ADU18, AP2204-18W5 trades PSRR and noise control for lower cost, while MCP1700T-1802E/TT sacrifices output current and control flexibility for extreme quiescent current reduction - making AP1152ADU18 the optimal choice for noise-critical, controllable, medium-current analog power domains.

Availability

AP1152ADU18 is available at Aetrix Electronics and suitable for RF power supplies, PLL/VCO biasing, and low-noise image sensor units requiring stable component supply across automotive, industrial, and medical design cycles.

Supply support for AP1152ADU18 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 manufacturer of discrete semiconductors and analog ICs, specializing in power management, signal integrity, and protection solutions for high-reliability applications.

The AP1152 series is designed specifically for low-noise, high-PSRR linear regulation in RF, imaging, and precision analog systems - emphasizing stability with small ceramics, integrated protection, and flexible on/off control.

FAQ

What is the minimum input voltage required for AP1152ADU18 to regulate 1.8 V output?

The AP1152ADU18 requires a minimum input voltage of 1.905 V under typical conditions (105 mV dropout at 100 mA). At full 300 mA load, dropout rises to 235 mV (per datasheet Table 2), so VIN must be ≥2.035 V. For guaranteed operation across temperature and process variation, maintain VIN ≥2.1 V - the specified lower limit of the operating voltage range.

Can AP1152ADU18 operate stably with a 0.1 µF ceramic output capacitor?

Yes - the AP1152ADU18 is explicitly characterized for stable operation with a 0.1 µF ceramic capacitor on VOUT when VOUT ≥ 2.5 V. For 1.8 V output, the datasheet recommends ≥0.22 µF (see Figure 3 and Section 11.4), but 0.1 µF may suffice in low-current, low-ESR layouts. Always verify stability with actual board parasitics and load transients.

How does the NP terminal affect AP1152ADU18 performance?

The NP (Noise Pass) terminal on AP1152ADU18 connects to an internal noise-filtering node. Adding a capacitor (0.001–0.1 µF) between NP and GND improves low-frequency PSRR and reduces output voltage noise - critical for RF and audio applications. Larger NP capacitance slows ON/OFF transition times but enhances ripple suppression below 100 kHz.

What is the function of the VCONT pin on AP1152ADU18?

VCONT is the high-active on/off control input for AP1152ADU18. Driving VCONT ≥1.8 V enables regulation; pulling VCONT <0.35 V disables output. An internal 500 kΩ pull-down resistor ensures default OFF state when unconnected. No external pull-up is needed, enabling direct interface with microcontroller GPIOs or logic gates.

Does AP1152ADU18 include thermal protection?

Yes - AP1152ADU18 integrates thermal shutdown protection that disables the output when junction temperature reaches ~150°C. Recovery occurs automatically once die temperature falls below the hysteresis threshold (~135°C). This protection works independently of over-current detection and is fully functional across the –40°C to +85°C ambient range.