NXP Semiconductors LD6816CX4/C12P,315

Overview

LD6816CX4/C12P from NXP Semiconductors is a 1.2 V fixed-output, 150 mA ultra-low-dropout linear regulator in a 0.76 mm × 0.76 mm WLCSP4 package with auto-discharge function (integrated pull-down transistor). It delivers 45 mV dropout at full load, 30 µV_RMS output noise (10 Hz–100 kHz), and 55 dB PSRR at 1 kHz-optimized for power-sensitive mobile interfaces in smartphones and portable media players.

For engineers reviewing the LD6816CX4/C12P datasheet, LD6816CX4/C12P pinout, LD6816CX4/C12P application, or LD6816CX4/C12P equivalent, key selection criteria include its 1.2 V output accuracy (±0.5% at +25°C), sub-150 µs startup time, 0.1 µA shutdown quiescent current, and backside-coated WLCSP4 package enabling high-density PCB layouts in space-constrained portable designs.

Technical Context

The LD6816CX4/C12P implements a PMOS pass transistor architecture with internal voltage reference, thermal shutdown (160°C), and overcurrent protection. Its enable input (active HIGH) controls both regulation and the integrated pull-down switch that actively discharges the output during disable-critical for fast power-state transitions in battery-powered systems.

Designed for stability with 1.0 µF X7R ceramic output capacitance (ESR 5–500 mΩ), it maintains regulation across −40°C to +85°C ambient while rejecting supply ripple via frequency-dependent PSRR peaking above 50 dB below 10 kHz. The backside coating enhances mechanical robustness and moisture resistance without altering electrical behavior.

Key Specifications

Pinout & Package

Package: Wafer-Level Chip-Scale Package (WLCSP4), 0.76 mm × 0.76 mm × 0.51 mm (typ.), 0.4 mm pitch, backside coated, RoHS-compliant and halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6219B122MR-G and RP114K121D-TR, LD6816CX4/C12P uniquely combines ultra-small WLCSP4 size, backside coating for reliability, and integrated auto-discharge-making it optimal for next-generation portable devices where board space, thermal resilience, and fast power-state transitions are co-constrained.

Availability

LD6816CX4/C12P is available at Aetrix Electronics and suitable for smartphone core power, portable media player audio rails, digital still camera sensor interfaces, and personal navigation device GPS front-ends requiring stable component supply with guaranteed long-term sourcing.

Supply support for LD6816CX4/C12P 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

NXP Semiconductors is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, and consumer electronics, with leadership in power management and RF technologies.

The LD6816 series was designed specifically for ultra-miniaturized portable electronics-delivering high-accuracy, low-noise, low-dropout regulation in wafer-level packages to meet aggressive size, efficiency, and reliability targets in smartphones and wearables.

FAQ

What is the nominal output voltage and tolerance of the LD6816CX4/C12P?

The LD6816CX4/C12P provides a fixed 1.2 V output voltage with ±0.5% tolerance at +25°C and ±4% over −40°C to +85°C ambient. This accuracy is maintained across 1 mA to 150 mA load current and input voltages from 2.3 V to 5.5 V, ensuring reliable operation for precision analog and digital core supplies in portable systems.

Does the LD6816CX4/C12P include an auto-discharge feature, and how does it work?

Yes, the LD6816CX4/C12P integrates an auto-discharge function via an internal 100 Ω pull-down transistor on the OUT pin. When the EN pin is driven LOW, this transistor actively discharges the output capacitor, achieving 10% of nominal voltage in under 300 µs-eliminating reliance on external bleeders and enabling fast, deterministic power-state transitions in battery-powered devices.

What package type and dimensions does the LD6816CX4/C12P use?

The LD6816CX4/C12P uses a wafer-level chip-scale package (WLCSP4) with backside coating, measuring 0.76 mm × 0.76 mm × 0.51 mm (typical height). It features a 2×2 bump array on 0.4 mm pitch and complies with RoHS, halogen-free, and dark green environmental standards-optimized for high-density, low-profile mobile PCB assemblies.

What is the minimum recommended output capacitor for stable operation of the LD6816CX4/C12P?

The LD6816CX4/C12P requires a minimum 0.7 µF ceramic output capacitor (X7R dielectric preferred) with ESR between 5 mΩ and 500 mΩ. For optimal transient response and stability, NXP recommends 1.0 µF ±30%, placed as close as possible to the OUT and GND pins. This value also influences shutdown timing, with larger capacitance extending discharge duration.

How does the LD6816CX4/C12P perform under thermal stress, and what protection mechanisms are included?

The LD6816CX4/C12P incorporates over-temperature protection that triggers shutdown at 160°C junction temperature, with 20 K hysteresis to prevent cycling. Its thermal resistance (R_th(j-a)) is 130 K/W on a standard two-layer PCB. Combined with the backside-coated WLCSP4 package, this enables reliable operation up to +85°C ambient-critical for thermally dense smartphone and wearable applications.