NXP Semiconductors LD6816CX4/28H,315

Overview

LD6816CX4/28H,315 from NXP Semiconductors is a 2.8 V fixed-output, 150 mA ultra-low-dropout linear regulator in WLCSP4 package, featuring 45 mV dropout at full load, 30 µV_RMS output noise (10 Hz–100 kHz), and high-ohmic (3-state) output during disable. It operates from 2.3 V to 5.5 V input and delivers stable power for noise-sensitive analog rails in mobile SoC subsystems.

For engineers reviewing the LD6816CX4/28H,315 datasheet, LD6816CX4/28H,315 pinout, LD6816CX4/28H,315 application, or LD6816CX4/28H,315 equivalent, this page provides verified electrical specs, thermal behavior, enable timing, PSRR performance at 1 kHz (−55 dB), and design-critical package dimensions for high-density portable PCB layouts.

Technical Context

The LD6816CX4/28H,315 uses a PMOS pass transistor architecture enabling ultra-low dropout and fast start-up (<150 µs). Its internal voltage reference and error amplifier maintain ±0.5% output accuracy at 25 °C with ±3% variation over −40 °C to +85 °C ambient.

It integrates over-temperature shutdown (160 °C trigger, 20 K hysteresis), current limiting (600 mA short-circuit), and ESD protection (±10 kV HBM). The active-HIGH enable pin (VIH ≥1.1 V, VIL ≤0.4 V) controls a high-impedance output state-no pull-down transistor-making it suitable for systems requiring floating-rail sequencing.

Key Specifications

Pinout & Package

LD6816CX4/28H,315 is housed in a 0.76 mm × 0.76 mm × 0.47 mm Wafer-Level Chip-Scale Package (WLCSP4) with 0.4 mm pitch and 4 solder bumps in 2×2 array. Package is Pb-free, 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 XC6219B282MR-G and RT9013-28GB, LD6816CX4/28H,315 offers superior noise performance (30 µV_RMS vs. ≥40 µV), lowest dropout (45 mV), and smallest footprint (0.76 mm²), making it optimal for space-constrained, battery-powered analog-intensive designs where power integrity is critical.

Availability

LD6816CX4/28H,315 is available at Aetrix Electronics and suitable for smartphone application processors, digital camera image sensors, portable media player audio codecs, and GPS RF front-ends requiring stable component supply with tight voltage tolerance and ultra-low noise.

Supply support for LD6816CX4/28H,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 electronics, with leadership in power management and RF technologies.

The LD6816 series was designed specifically for ultra-miniaturized, battery-powered portable devices demanding ultra-low dropout, low noise, and high reliability in wafer-level packaging - targeting next-generation smartphones, wearables, and IoT edge sensors.

FAQ

What is the nominal output voltage and tolerance of LD6816CX4/28H,315?

The LD6816CX4/28H,315 delivers a fixed 2.8 V output with ±2% tolerance at +25 °C and ±3% over the full operating temperature range (−40 °C to +85 °C). This accuracy is guaranteed across 1 mA to 150 mA load currents and input voltages from 2.845 V to 5.5 V, ensuring reliable operation in precision analog and digital I/O domains without external trimming.

Does LD6816CX4/28H,315 include an auto-discharge function?

No, LD6816CX4/28H,315 does not include an auto-discharge function. As indicated by the "H" suffix, it features a high-ohmic (3-state) output during disable - meaning the OUT pin floats rather than being actively pulled to GND. This behavior is confirmed in Section 1.1 and Table 3 of the datasheet, distinguishing it from "P" and "CxxP" variants that integrate a pull-down transistor.

What is the recommended output capacitor for LD6816CX4/28H,315?

The LD6816CX4/28H,315 requires a minimum 1.0 µF X7R ceramic capacitor at the OUT pin, with ESR between 5 mΩ and 500 mΩ. The datasheet specifies 1.0 µF as the typical value (Table 10), and recommends X7R dielectric to maintain capacitance stability across −40 °C to +125 °C. Using less than 0.7 µF risks instability and degraded transient response.

How does the PSRR of LD6816CX4/28H,315 perform at high frequencies?

LD6816CX4/28H,315 achieves −55 dB PSRR at 1 kHz (Table 9), but its PSRR degrades above 10 kHz - dropping to approximately −25 dB at 100 kHz per Figure 4. This frequency-dependent rejection is inherent to its internal error amplifier bandwidth and makes it most effective against low-frequency ripple from DC-DC converters, not high-frequency switching noise.

What is the thermal resistance and maximum junction temperature of LD6816CX4/28H,315?

LD6816CX4/28H,315 has a typical junction-to-ambient thermal resistance (R_th(j-a)) of 130 K/W under standard two-layer PCB conditions (Table 8). Its absolute maximum junction temperature is +125 °C (Table 6), with thermal shutdown activating at +160 °C (T_sd) and 20 K hysteresis (T_sd(hys)). Proper copper pour under the WLCSP4 package is essential to maintain safe operating temperatures at 150 mA load.