Diodes Incorporated AP7348D-3612RS4-7

Overview

AP7348D-3612RS4-7 from Diodes Incorporated is a quad-channel low-dropout linear regulator IC with independent enable control, delivering 300mA per channel, ±1% output voltage accuracy, 75dB PSRR at 1kHz, and 60µV_rms output noise (10Hz–100kHz). It integrates two voltage references, foldback current limiting, thermal shutdown per channel, and auto-discharge circuitry. Designed for multi-rail power management in compact portable electronics, it powers distinct voltage domains such as RF transceivers and camera sensor cores.

For engineers reviewing the AP7348D-3612RS4-7 datasheet, AP7348D-3612RS4-7 pinout, AP7348D-3612RS4-7 application, or AP7348D-3612RS4-7 equivalent, key selection criteria include per-channel enable independence (EN1 controls VOUT1/VOUT3; EN2 controls VOUT2/VOUT4), fixed dual-output configuration (3.6V/1.2V), thermal fault behavior (all channels disabled on overtemperature), and X1-DFN1612-8 (Type B) package constraints for high-density PCB layout.

Technical Context

The AP7348D-3612RS4-7 implements four independent CMOS-based LDO regulators sharing a common input (VDD) and ground (GND), each with dedicated error amplifier, discharge FET, and resistor network for fixed output setting. Its architecture supports simultaneous or staggered channel activation via two logic-level enable inputs.

Each channel features foldback current limiting (55mA short-circuit clamp), per-channel overtemperature detection (155°C trip with 25°C hysteresis), and automatic output discharge when disabled. The device maintains stability with 1µF ceramic output capacitors and requires a minimum 4.7µF input capacitor for transient immunity.

Key Specifications

Pinout & Package

The AP7348D-3612RS4-7 is housed in the X1-DFN1612-8 (Type B) 1.6mm × 1.2mm, 0.4mm pitch, thermally enhanced DFN package with exposed thermal pad. This ultra-compact footprint supports high-density mobile PCB layouts while enabling efficient heat dissipation via the thermal pad (θ_JA = 160°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6216D3612MR-G and RP517K3612D-TR, the AP7348D-3612RS4-7 uniquely balances dual-group enable flexibility, industry-leading PSRR/noise trade-off, and minimal footprint-making it optimal for space-constrained, multi-rail portable designs where sequencing and noise isolation are co-priorities.

Availability

AP7348D-3612RS4-7 is available at Aetrix Electronics and suitable for smartphone baseband, IoT LPWAN modules, and camera sensor applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for AP7348D-3612RS4-7 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-reliability power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.

The AP7348 belongs to Diodes' high-PSRR, low-noise LDO family designed specifically for multi-rail power delivery in battery-powered portable electronics where compact size, sequencing control, and RF-sensitive noise performance are critical.

FAQ

What are the exact output voltages configured for AP7348D-3612RS4-7?

The suffix "3612" explicitly defines the output configuration: Channel 1 and Channel 3 deliver a fixed 3.6V output, while Channel 2 and Channel 4 deliver a fixed 1.2V output. These values are factory-trimmed and non-adjustable; no external feedback resistors are required or supported. The device does not support programmable or adjustable outputs.

How does thermal shutdown behave across the four channels?

Each channel has an independent overtemperature sensor. If any single channel reaches 155°C, all four outputs are immediately disabled simultaneously to prevent cascading failure. Recovery occurs only after junction temperature falls below 130°C (155°C – 25°C hysteresis), and all enable pins must be reasserted to restart regulation. This behavior is hardwired and cannot be disabled.

Can AP7348D-3612RS4-7 operate with input voltage below 2.0V?

Yes - the device supports VDD as low as 1.7V. However, dropout voltage increases significantly below 2.0V input: for the 1.2V outputs, dropout is 0.51V (typ.) at 300mA, meaning minimum functional VDD is 1.71V. For reliable 300mA delivery at 1.2V, maintain VDD ≥ 1.8V. Below 1.7V, operation is outside Absolute Maximum Ratings and may cause permanent damage.

Is the thermal pad electrically connected, and what is its role?

The exposed thermal pad is electrically isolated from all internal circuitry and may be left floating or connected to GND. Its sole purpose is thermal conduction: soldering it to a copper pour significantly improves heat dissipation, lowering θ_JA from 160°C/W to ~65°C/W in typical layouts. Failure to solder the pad risks thermal shutdown under full 300mA load per channel.