Diodes Incorporated AP7350-18CF4-7

Overview

AP7350-18CF4-7 from Diodes Incorporated is a 1.8V fixed-output, 150mA ultra-low quiescent current LDO regulator in a wafer-level chip-scale X2-WLB0606-4 package. It delivers ±1% output voltage accuracy over temperature, features 0.25µA typical quiescent current and 0.02µA standby current, and operates across 2.0V–5.25V input range - optimized for battery-powered wearable electronics and IoT sensor modules where board space and energy efficiency are critical.

For engineers reviewing the AP7350-18CF4-7 datasheet, AP7350-18CF4-7 pinout, AP7350-18CF4-7 application, or AP7350-18CF4-7 equivalent, key selection criteria include dropout voltage at 150mA (0.33V typ. @1.8V), EN-controlled shutdown capability, thermal resistance (267°C/W), and compatibility with 0.1µF ceramic input/output capacitors in space-constrained layouts.

Technical Context

The AP7350-18CF4-7 integrates a precision voltage reference, error amplifier, current-limit circuit, and enable logic to deliver stable 1.8V regulation with minimal external components. Its architecture supports fast load transient response (e.g., 1→50mA step at VOUT=1.2V/3.3V) and maintains stability with low-ESR ceramic capacitors as small as 0.1µF.

It operates without internal active discharge (non-D variant), relies on external capacitor discharge paths, and uses SnAgCu solderable micro-balls for reliable reflow attachment. The device meets JESD 22 ESD standards (4kV HBM, 400V MM) and JESD 78 latch-up immunity (>400mA), ensuring robustness in portable end-equipment.

Key Specifications

Pinout & Package

The AP7350-18CF4-7 uses the X2-WLB0606-4 wafer-level chip-scale package with four SnAgCu solder balls. Dimensions: 0.64mm × 0.64mm × 0.34mm; weight ≈0.01g. Pin 1 (EN) is located at bottom-left corner when viewed from top (marking side); ball layout matches JEDEC MO-254 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-1802E/TO and XC6206P182MR-G, the AP7350-18CF4-7 offers the smallest footprint, lowest quiescent current, and tightest dropout - making it optimal for next-generation wearables and miniaturized IoT endpoints where size and battery life are primary constraints.

Availability

AP7350-18CF4-7 is available at Aetrix Electronics and suitable for wearable electronics, IoT sensor modules, and compact camera power systems requiring stable component supply, long-term lifecycle support, and consistent wafer-level packaging performance.

Supply support for AP7350-18CF4-7 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-efficiency power management, signal integrity, and protection solutions for consumer, industrial, and automotive markets.

The AP7350 series belongs to Diodes' ultra-low-IQ LDO portfolio, designed specifically for energy-constrained portable and wireless devices where extended battery life and minimal PCB area are essential design goals.

FAQ

What is the minimum input voltage required to maintain 1.8V output at 150mA load?

The AP7350-18CF4-7 requires VIN ≥ 2.13V to sustain 1.8V output at 150mA, based on its maximum dropout voltage of 0.33V at that load and temperature. Below this threshold, regulation is lost and VOUT drops linearly with VIN. This enables use with partially discharged single-cell lithium batteries.

Can the EN pin be left unconnected if always-on operation is needed?

No - the EN pin must never be left floating. For continuous operation, tie EN directly to VIN using a short trace. Leaving it open risks undefined behavior due to leakage currents, potentially causing intermittent shutdown or excessive ground current. A pull-up resistor is unnecessary and adds parasitic leakage.

Is an output capacitor mandatory, and what type is recommended?

Yes - a minimum 0.1µF ceramic capacitor (X5R/X7R) is mandatory at VOUT for stability and transient response. Place it within 1mm of the VOUT and GND balls. Larger values (e.g., 1–10µF) improve load-step immunity but are not required for basic regulation. Avoid tantalum or aluminum electrolytic types due to ESR and reliability concerns.

Does AP7350-18CF4-7 include internal reverse-current protection?

No - the AP7350-18CF4-7 does not integrate reverse-current blocking. If VIN can fall below VOUT (e.g., during hot-swap or backup battery switchover), external protection (e.g., series Schottky diode or ideal diode controller) is required to prevent backfeed from VOUT into VIN, which may damage upstream sources or cause system instability.