Diodes Incorporated AP7353D-36CV4-7

Overview

AP7353D-36CV4-7 from Diodes Incorporated is a 250mA low-dropout linear regulator with fixed 3.6V output, ±1% accuracy, 90dB PSRR at 1kHz, 10µV_rms output noise (10Hz–100kHz), and 18µA typical quiescent current. It features enable control, thermal shutdown, short-circuit protection, and integrated auto-discharge functionality. Designed for RF supply rails in portable communication devices requiring ultra-low noise and high power-supply rejection.

For engineers reviewing the AP7353D-36CV4-7 datasheet, AP7353D-36CV4-7 pinout, AP7353D-36CV4-7 application, or AP7353D-36CV4-7 equivalent, key selection criteria include dropout voltage at 250mA (60mV typ. @ 3.6V), EN logic thresholds (0.4V_IL/1.2V_IH), thermal resistance (150°C/W), and compatibility with 1µF ceramic output capacitors in space-constrained layouts.

Technical Context

The AP7353D-36CV4-7 implements a CMOS-based LDO architecture with a precision voltage reference, error amplifier, current-limit circuit, and NMOS pass transistor with built-in discharge path. Its auto-discharge function actively pulls the output to ground when disabled, preventing residual voltage hold-up in battery-sensitive systems.

It operates across 2.0V–5.5V input range and maintains regulation down to 60mV dropout at 250mA load for V_OUT = 3.6V. Fast load transient response (<20µs settling) and high PSRR (70dB @ 10kHz, 250mA) make it suitable for powering noise-sensitive analog and RF circuitry adjacent to digital switching domains.

Key Specifications

Pinout & Package

X1-WLB0707-4 (Type A1) wafer-level chip-scale package (0.64mm × 0.64mm, 0.4mm height) with 4 solder bumps and exposed thermal pad (EP). Optimized for ultra-dense PCB layouts in smartphones and wearables.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1703T-3602E/MB and XC6210B362MR-G, the AP7353D-36CV4-7 uniquely combines 250mA output, 90dB PSRR at 1kHz, auto-discharge, and 0.64mm × 0.64mm WLCSP-making it optimal for miniaturized, battery-sensitive RF and imaging subsystems where size, noise, and fast shutdown are co-constrained.

Availability

AP7353D-36CV4-7 is available at Aetrix Electronics and suitable for smartphone camera modules, Bluetooth LE audio transceivers, and wearable biosensor systems requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for AP7353D-36CV4-7 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 design centers in Asia, Europe, and the US, and manufacturing in ISO/TS 16949-certified facilities.

The AP7353 series belongs to Diodes' high-performance LDO portfolio targeting portable and wireless applications-designed specifically for ultra-low noise, high PSRR, and minimal footprint in battery-powered RF and imaging systems.

FAQ

What is the minimum input voltage required for AP7353D-36CV4-7 to maintain regulation at 250mA?

The minimum input voltage is calculated as V_OUT + V_DO = 3.6V + 0.060V = 3.66V (typical dropout). At worst-case 237mV (max), VIN must be ≥3.837V. This allows reliable operation from fully charged single-cell Li-ion (4.2V) or regulated 3.9V buck outputs.

Does AP7353D-36CV4-7 require an external discharge resistor?

No. The "D" suffix indicates integrated auto-discharge functionality via a 35Ω NMOS switch between OUT and GND. When EN is low, this path actively discharges the output capacitor-eliminating need for external resistors and reducing BOM count and board area.

Can AP7353D-36CV4-7 be used with ceramic capacitors smaller than 1µF?

The datasheet specifies 0.7µF minimum effective capacitance accounting for temperature, DC bias, and tolerance derating. A 1µF X7R capacitor typically retains >0.85µF at 3.6V bias and 85°C, satisfying stability requirements. Capacitors below 0.7µF risk oscillation or poor transient response.

How does the exposed thermal pad (EP) affect thermal performance?

The EP is electrically isolated but thermally coupled to the die. Connecting it to ≥25mm² of internal/external GND copper reduces θ_JA from 150°C/W to ~65°C/W in multi-layer boards. Leaving it unconnected degrades thermal resistance by >40%, risking thermal shutdown above 150mA continuous load.