Diodes Incorporated AP7348D-1833RS4-7

Overview

AP7348D-1833RS4-7 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 1.8V on channels 1 & 2 and 3.3V on channels 3 & 4, operating from 1.7V to 5.25V input, and is optimized for RF supply in LPWAN/IoT modules where low noise and channel isolation are critical.

For engineers reviewing the AP7348D-1833RS4-7 datasheet, AP7348D-1833RS4-7 pinout, AP7348D-1833RS4-7 application, or AP7348D-1833RS4-7 equivalent, this device supports simultaneous dual-rail power delivery with thermal shutdown per channel, auto-discharge on disable, and stable operation with 1µF ceramic output capacitors - key for compact, battery-powered communication subsystems.

Technical Context

The AP7348D-1833RS4-7 integrates four independent CMOS-based LDO regulators sharing one VDD input and two enable inputs, each with dedicated error amplifiers, foldback current limiting, and thermal sensing. Its architecture enables selective powering of mixed-voltage subsystems - e.g., 1.8V sensor interface and 3.3V RF transceiver - without cross-talk.

Each channel features an internal discharge FET (R_ON ≈ 10Ω) activated during disable, ensuring rapid VOUT decay to prevent floating nodes. Over-temperature protection triggers at +155°C with +25°C hysteresis, disabling all four outputs simultaneously while preserving channel-level fault isolation during normal operation.

Key Specifications

Pinout & Package

X1-DFN1612-8 (Type B) package: 1.6mm × 1.2mm, 0.4mm pitch, exposed thermal pad (electrically isolated but thermally connected to GND for dissipation).

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6217D1833MR-G and RP517K1833-TR, the AP7348D-1833RS4-7 uniquely combines 300mA/channel capability, per-channel thermal shutdown, and integrated auto-discharge in a 1.6mm × 1.2mm footprint - making it optimal for space-constrained, thermally demanding LPWAN and camera modules.

Availability

AP7348D-1833RS4-7 is available at Aetrix Electronics and suitable for LPWAN modem power, IoT sensor hubs, camera module bias, and Wi-Fi 6 access point designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for AP7348D-1833RS4-7 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 power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.

The AP7348 series belongs to Diodes' high-PSRR, low-noise LDO portfolio, designed specifically for powering noise-sensitive RF and mixed-signal circuits in battery-operated wireless devices.

FAQ

What are the exact output voltages configured in AP7348D-1833RS4-7?

This part delivers fixed 1.8V on VOUT1 and VOUT2, and fixed 3.3V on VOUT3 and VOUT4. The suffix "1833" explicitly denotes this dual-rail configuration per the Diodes ordering matrix. No external resistors are required - output voltages are factory-trimmed and non-adjustable.

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 outputs simultaneously. However, doing so forfeits independent sequencing capability. When tied, ensure the driving source meets both pins' input thresholds (V_IL ≤ 0.5V, V_IH ≥ 1.3V) and can sink/source sufficient current for both inputs.

What is the maximum allowable power dissipation per the datasheet?

The absolute maximum power dissipation is 600mW, derived from the θ_JA = 160°C/W rating and T_JMAX = +155°C. Exceeding this causes thermal shutdown. At 300mA per channel and 0.26V dropout (3.3V output), worst-case dissipation is ~312mW - well within limit if ambient stays ≤ +85°C and thermal pad is properly soldered.

Is the thermal pad electrically connected internally?

No - the exposed thermal pad is electrically isolated from all internal circuitry. It may be left floating or connected to GND for improved thermal performance. Pin 1 (GND) remains the mandatory electrical ground connection; the pad serves only thermal conduction, not signal return.