Diodes Incorporated AP7340D-285FS4-7

Overview

AP7340D-285FS4-7 from Diodes Incorporated is a 2.85V fixed-output, 150mA low-dropout linear regulator with ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). Built on CMOS process, it features enable control, thermal shutdown, short-circuit protection, and operates from 1.7V to 5.25V input. It powers RF supply rails in portable wireless communication devices requiring stable, low-noise bias.

For engineers reviewing the AP7340D-285FS4-7 datasheet, AP7340D-285FS4-7 pinout, AP7340D-285FS4-7 application, or AP7340D-285FS4-7 equivalent, key selection criteria include dropout voltage at 150mA (0.21–0.27V), quiescent current (35µA typ), EN logic thresholds (0.5V low / 1.3V high), and X2-DFN1010-4 package thermal performance.

Technical Context

The AP7340D integrates a precision voltage reference, error amplifier, current-limit circuit, and NMOS pass transistor with auto-discharge functionality-distinguishing it from the non-discharge AP7340 variant. Its CMOS architecture enables ultra-low quiescent current and fast load transient response.

It delivers regulated 2.85V output with guaranteed ±1% accuracy over -40°C to +85°C, supports 150mA continuous load, and maintains stability with 0.47µF ceramic input/output capacitors. The EN pin provides active-high logic control with defined turn-on/turn-off voltage thresholds and sub-1µA standby leakage.

Key Specifications

Pinout & Package

X2-DFN1010-4 (1.0mm × 1.0mm, 0.4mm pitch, thermal pad) - ultra-compact footprint optimized for space-constrained mobile PCBs; thermal pad must be connected to GND plane for effective heat dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-285E/TT and XC6219B285MR-G, AP7340D-285FS4-7 uniquely combines 150mA capability, 75dB PSRR, 60µV_rms noise, EN control, and auto-discharge in a 1.0mm² DFN-making it optimal for compact, noise-sensitive, sequenced RF and imaging power domains.

Availability

AP7340D-285FS4-7 is available at Aetrix Electronics and suitable for RF power amplifier bias, camera module core supply, wireless adapter SoC core, and portable media player audio codec applications requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for AP7340D-285FS4-7 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 solutions for power management, signal integrity, and connectivity applications.

The AP7340 series targets portable electronics requiring ultra-low-noise, high-PSRR LDOs with enable and discharge functions-designed specifically for RF, imaging, and battery-sensitive subsystems in smartphones, tablets, and wireless peripherals.

FAQ

What is the purpose of the thermal pad on the AP7340D-285FS4-7 package?

The exposed thermal pad on the X2-DFN1010-4 package serves as the primary heat dissipation path. It must be soldered to a large copper area connected to the PCB ground plane to maintain junction temperature within safe limits under 150mA load. Leaving it unconnected reduces thermal performance by >40%, risking thermal shutdown during sustained operation.

Does AP7340D-285FS4-7 require external capacitors, and what values are recommended?

Yes: a minimum 0.47µF ceramic capacitor is required between VIN and GND, and another 0.47µF ceramic capacitor between VOUT and GND. These must be placed within 2mm of their respective pins. Larger bulk capacitors (e.g., 10µF tantalum) may be added in parallel for high-dV/dt loads, but the 0.47µF ceramics are mandatory for stability and transient response.

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

The auto-discharge FET activates only when the EN pin is driven low (≤0.5V), connecting VOUT to GND through a ~30Ω path. This rapidly discharges output capacitance to prevent residual voltage from interfering with power sequencing or causing back-powering of upstream circuits. It remains inactive during normal operation or when EN is floating (which is prohibited).

Can AP7340D-285FS4-7 be used with input voltages below 1.7V?

No. The absolute minimum input voltage is 1.7V per datasheet specifications. Operation below this threshold results in loss of regulation, increased dropout, and potential instability. For sub-1.7V applications, consider alternative LDOs with lower V_IN(min) such as the AP2210 (1.0V min), but note that output accuracy and PSRR degrade significantly near V_IN(min).