Diodes Incorporated AP7348D-2833RS4-7

Overview

AP7348D-2833RS4-7 from Diodes Incorporated is a quad-channel, 300mA low-dropout linear regulator with independent enable control (EN1 for VOUT1/VOUT3; EN2 for VOUT2/VOUT4), ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). It delivers fixed 2.8V on channels 1 & 2 and 3.3V on channels 3 & 4, in an X1-DFN1612-8 (Type B) package, targeting multi-rail power management in compact RF and imaging subsystems.

For engineers reviewing the AP7348D-2833RS4-7 datasheet, AP7348D-2833RS4-7 pinout, AP7348D-2833RS4-7 application, or AP7348D-2833RS4-7 equivalent, this page provides verified electrical parameters, thermal shutdown behavior per channel, discharge circuit operation during disable, and layout-critical ESR vs. load current guidance - all confirmed from Diodes' DS42124 Rev. 3-2.

Technical Context

The AP7348D-2833RS4-7 integrates two independent CMOS-based LDO regulators per enable input: EN1 controls two 2.8V outputs (VOUT1, VOUT3), while EN2 controls two 3.3V outputs (VOUT2, VOUT4). Each channel features foldback current limiting (55mA short-circuit clamp), individual overtemperature sensing (155°C shutdown with 25°C hysteresis), and auto-discharge via 10Ω N-channel switch when disabled.

It operates across 1.7V–5.25V input range with total quiescent current of 160µA (typ.) when both enables are high, and achieves 0.26V dropout (typ.) at 300mA for 2.8V outputs and 0.25V for 3.3V outputs - enabling stable regulation even under tight input-output margins in battery-powered systems.

Key Specifications

Pinout & Package

The AP7348D-2833RS4-7 is housed in an X1-DFN1612-8 (Type B) 1.6mm × 1.2mm, 0.4mm pitch, thermally enhanced package with exposed thermal pad. The pad must be soldered to PCB ground plane for thermal dissipation but is electrically optional.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AP7349D-2833RS4-7, the AP7348D-2833RS4-7 trades soft-start capability for lower unit cost and identical core regulation performance; versus TPL7407LDR, it delivers 25dB higher PSRR, half the output noise, and true quad-channel independence - making it the only option meeting stringent RF and imaging power integrity requirements.

Availability

AP7348D-2833RS4-7 is available at Aetrix Electronics and suitable for smartphone baseband power, Wi-Fi 6 transceiver bias, IoT camera modules, and LPWAN sensor nodes requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for AP7348D-2833RS4-7 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, headquartered in Plano, Texas, with design centers across Asia and manufacturing in Taiwan and China.

The AP7348 belongs to Diodes' high-PSRR, low-noise LDO family designed specifically for multi-rail power management in portable wireless and imaging devices where board space, thermal density, and signal integrity are critical constraints.

FAQ

What is the maximum allowable power dissipation for AP7348D-2833RS4-7?

The absolute maximum power dissipation is 600mW, as specified in the Absolute Maximum Ratings table. Exceeding this limit triggers thermal shutdown at +155°C. To stay within this limit, ensure the sum of (VDD − VOUT) × IOUT across all active channels remains ≤600mW - for example, at VDD = 4.2V, 2.8V/300mA + 3.3V/300mA yields 420mW, leaving margin for ambient temperature rise.

Can EN1 and EN2 be tied together for single-enable operation?

Yes, EN1 and EN2 may be connected to a common control signal, enabling all four channels simultaneously. However, doing so eliminates independent sequencing capability and forces identical power states for both 2.8V and 3.3V domains - which may conflict with system boot requirements where staggered rail activation is needed to prevent inrush current peaks.

Is the thermal pad electrically connected to GND internally?

No, the thermal pad is electrically isolated from all internal circuitry. It must be soldered to the PCB ground plane solely for thermal conduction. While it may be left floating electrically, Diodes recommends connecting it to GND to improve thermal performance and reduce EMI coupling - but this connection does not replace the mandatory GND pin (Pin 1) connection.

How does the foldback current limiting behave during short-circuit events?

When any VOUT pin is shorted to GND, the corresponding channel limits output current to approximately 55mA (typ.), preventing thermal runaway. This foldback behavior reduces power dissipation during fault conditions and allows safe recovery once the short is removed - unlike constant-current limiters that sustain full 300mA into a short, risking device damage.