NXP Semiconductors LD6816CX4/C14P,315

Overview

LD6816CX4/C14P,315 from NXP Semiconductors is a 1.4 V fixed-output, 150 mA ultra-low-dropout linear regulator in WLCSP4 package (0.76 mm × 0.76 mm × 0.47 mm), featuring 45 mV dropout at full load, 30 µV_RMS output noise (10 Hz–100 kHz), and auto-discharge functionality via integrated pull-down transistor. It operates from 2.3 V to 5.5 V input and targets power-sensitive portable applications requiring stable low-voltage rails.

For engineers reviewing the LD6816CX4/C14P,315 datasheet, LD6816CX4/C14P,315 pinout, LD6816CX4/C14P,315 application, or LD6816CX4/C14P,315 equivalent, key selection criteria include its 1.4 V fixed output, sub-100 mV dropout performance, enable-controlled shutdown with <300 µs discharge time, WLCSP miniaturization, and PSRR of −55 dB at 1 kHz - all critical for battery-powered mobile interface supplies.

Technical Context

The LD6816CX4/C14P,315 implements a PMOS pass transistor architecture enabling ultra-low dropout voltage and high PSRR across frequency. Its internal reference and error amplifier maintain tight output regulation over temperature (±3% max variation from −40 °C to +85 °C) and load (1 mA to 150 mA).

Unlike high-ohmic disable variants, this part integrates a dedicated pull-down switch (R_pd = 100 Ω typical) that actively discharges the output capacitor during shutdown, eliminating residual voltage hold-up in cascaded supply domains. Thermal shutdown (160 °C) and current limiting (600 mA short-circuit) provide robust fault protection.

Key Specifications

Pinout & Package

Package: Wafer-Level Chip-Scale Package (WLCSP4), 0.4 mm pitch, 0.76 mm × 0.76 mm × 0.47 mm footprint with backside coating (per ordering code "C" suffix). Compliant with RoHS, halogen-free, and MSL3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XC6210B142MR-G and RP111N141B-TR-F, LD6816CX4/C14P,315 uniquely combines ultra-low dropout (45 mV), integrated auto-discharge, and industry-standard WLCSP4 footprint - making it optimal for space-constrained, multi-rail portable systems requiring deterministic power sequencing.

Availability

LD6816CX4/C14P,315 is available at Aetrix Electronics and suitable for smartphone baseband supplies, digital camera sensor bias, portable media player audio codecs, and Bluetooth LE I/O domains requiring stable component supply with guaranteed long-term availability.

Supply support for LD6816CX4/C14P,315 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 applications, with leadership in power management and RF technologies.

The LD6816 series was designed specifically for ultra-miniaturized, battery-powered portable electronics demanding high efficiency, low noise, and fast dynamic response in sub-2 mm² footprints - targeting next-generation smartphones, wearables, and IoT edge devices.

FAQ

What is the nominal output voltage of the LD6816CX4/C14P,315?

The LD6816CX4/C14P,315 delivers a fixed 1.4 V output voltage with ±2% tolerance at +25 °C and ±3% over the full operating temperature range (−40 °C to +85 °C). This value is confirmed by Table 5 in the NXP datasheet, which maps the "C14P" suffix to 1.4 V nominal output in the WLCSP4 package with backside coating.

Does the LD6816CX4/C14P,315 include an auto-discharge function?

Yes, the LD6816CX4/C14P,315 integrates an active pull-down transistor that provides low-ohmic output discharge during shutdown. With a typical pull-down resistance of 100 Ω, it discharges a 1 µF output capacitor to 5% of V_OUT in under 300 µs - a feature explicitly defined for "CxxP" variants in Section 1.1 and Table 5 of the datasheet.

What package type and dimensions does the LD6816CX4/C14P,315 use?

The LD6816CX4/C14P,315 uses a Wafer-Level Chip-Scale Package (WLCSP4) with backside coating, measuring 0.76 mm × 0.76 mm × 0.47 mm and 0.4 mm bump pitch. Dimensions are specified in Table 15 and Figure 25 of the NXP datasheet, confirming the "C" prefix denotes the coated variant optimized for mechanical robustness in fine-pitch assembly.

What is the maximum input voltage rating for the LD6816CX4/C14P,315?

The LD6816CX4/C14P,315 supports an absolute maximum input voltage of +6.0 V for transient conditions up to 4 ms, with recommended continuous operation between 2.3 V and 5.5 V (Table 6 and Table 7). Exceeding 5.5 V continuously risks exceeding thermal limits or degrading long-term reliability.

How does the LD6816CX4/C14P,315 achieve its low output noise performance?

The LD6816CX4/C14P,315 achieves 30 µV_RMS output noise (10 Hz–100 kHz) through optimized internal bandgap reference design, low-noise error amplifier topology, and careful layout isolation within the monolithic silicon die. This value is measured with 1 µF output capacitance and zero load current, as specified in Table 9 of the datasheet.

Is the LD6816CX4/C14P,315 RoHS and halogen-free compliant?

Yes, the LD6816CX4/C14P,315 is Pb-free, RoHS compliant, and free of halogen and antimony per NXP's "dark green" compliance standard, as stated in Section 1.2 of the datasheet. This ensures environmental compliance for global consumer electronics markets including EU and China RoHS directives.