Diodes Incorporated AP7345D-3328RH4-7

Overview

AP7345D-3328RH4-7 from Diodes Incorporated is a dual-channel, CMOS-based low-dropout linear regulator delivering fixed 3.3V and 2.8V outputs with ±1% accuracy, 300mA per channel, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). It operates from 1.7V to 5.25V input, features independent enable pins (EN1/EN2), and targets power-sensitive dual-rail systems in portable RF and imaging subsystems.

For engineers reviewing the AP7345D-3328RH4-7 datasheet, AP7345D-3328RH4-7 pinout, AP7345D-3328RH4-7 application, or AP7345D-3328RH4-7 equivalent, this device supports precise dual-voltage sequencing in space-constrained mobile designs where low quiescent current (50µA per active channel), thermal robustness (150°C shutdown), and stable ceramic-capacitor operation are critical selection criteria.

Technical Context

The AP7345D-3328RH4-7 integrates two independent LDO regulators on a single X2-DFN1612-8 die, each with dedicated error amplifier, voltage reference, current-limit circuit, and NMOS pass transistor. Its CMOS architecture enables ultra-low quiescent current and fast load transient response (e.g., <20µs recovery for 50mA→300mA step at V_OUT=3.3V).

Each channel supports independent enable control with defined logic thresholds (EN high ≥1.3V, EN low ≤0.5V) and built-in auto-discharge via 30Ω internal N-channel switch when disabled. Thermal shutdown (150°C) with 20°C hysteresis and short-circuit foldback (~55mA) provide system-level protection without external components.

Key Specifications

Pinout & Package

The AP7345D-3328RH4-7 is housed in an X2-DFN1612-8 package (1.6mm × 1.2mm, 0.4mm height) with exposed thermal pad for enhanced heat dissipation. PCB layout requires connection of the thermal pad to GND plane for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A202833DQNR and NCP114AMX3328TBG, the AP7345D-3328RH4-7 uniquely combines wide-input operation (1.7V), auto-discharge, and industry-leading PSRR/noise trade-off in a 1.6mm×1.2mm footprint - making it optimal for next-gen compact battery-powered RF and imaging systems.

Availability

AP7345D-3328RH4-7 is available at Aetrix Electronics and suitable for smartphone baseband power, RF transceiver supply, and mobile camera module applications requiring stable component supply, consistent parametric performance across temperature, and long-term production continuity.

Supply support for AP7345D-3328RH4-7 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 manufacturer of discrete semiconductors and analog ICs, specializing in high-performance power management, signal integrity, and protection solutions for consumer, industrial, and communications markets.

The AP7345D belongs to Diodes' high-PSRR, low-noise LDO family designed specifically for battery-powered portable electronics where dual-rail efficiency, small footprint, and immunity to switching noise are essential design constraints.

FAQ

What are the recommended input and output capacitors for AP7345D-3328RH4-7?

A minimum 1.0µF ceramic capacitor is required between each VIN pin and GND, placed as close as possible to the device to suppress input supply glitches. Each VOUT pin requires a 1.0µF ceramic capacitor to ground for stability and transient response; low-ESR types are mandatory. Layout best practice mandates short, wide traces to both capacitors and direct connection of GND pins to a solid ground plane.

How does the auto-discharge feature operate, and when is it active?

The auto-discharge function activates automatically when either EN1 or EN2 is pulled low, connecting the corresponding VOUT pin to GND through an internal 30Ω NMOS transistor. This discharges residual output capacitance within ~1ms (for 1µF COUT), preventing floating voltages that could cause latch-up in downstream logic. The feature is inactive when the enable pin is high or floating (though floating is prohibited per datasheet).

Can AP7345D-3328RH4-7 operate with input voltage below 2.0V?

Yes - the AP7345D-3328RH4-7 is specified to operate from 1.7V to 5.25V input. At 3.3V output, its dropout voltage is 0.22V (max) at 300mA, meaning it regulates down to 3.52V input. For 2.8V output, dropout is 0.25V (max), allowing regulation from 3.05V input. Below those points, the device enters dropout but remains functional until VIN drops below absolute minimum 1.7V.

What thermal considerations apply to the X2-DFN1612-8 package in high-load conditions?

The X2-DFN1612-8 package relies on the exposed thermal pad for heat dissipation. To maintain junction temperature below 125°C at 300mA per channel, the thermal pad must be soldered to a ≥25mm² copper area connected to GND. With 2-layer PCB and 1oz copper, θ_JA is ~190°C/W; adding thermal vias reduces this to ~120°C/W. Thermal shutdown triggers at 150°C with 20°C hysteresis, ensuring safe recovery after transient overload.