NXP Semiconductors LD6815TD/15H,125

Overview

LD6815TD/15H from NXP Semiconductors is a fixed-output 1.5 V, 150 mA low-dropout linear regulator with ultra-high PSRR (75 dB at 1 kHz), 250 mV dropout at full load, and high-ohmic (3-state) output in shutdown mode. It operates from 2.3 V to 5.5 V input and delivers ultra-low RMS noise (40 µV, 10 Hz–100 kHz), making it suitable for powering noise-sensitive analog and RF circuitry in portable consumer devices.

For engineers reviewing the LD6815TD/15H datasheet, LD6815TD/15H pinout, LD6815TD/15H application, or LD6815TD/15H equivalent, key selection criteria include its 1.5 V fixed output, TSOP5 (SOT753) package, 0.1 µA shutdown quiescent current, auto-discharge absence (high-ohmic disable), and compatibility with 0.7–1.0 µF X7R ceramic output capacitors.

Technical Context

The LD6815TD/15H employs a PMOS pass transistor architecture enabling ultra-low dropout and high PSRR without requiring an external bias supply. Its enable input (active HIGH) controls a precision internal reference and error amplifier, delivering tight output voltage accuracy (±0.5% typ. at 25 °C, ±3% over −40 °C to +85 °C).

Unlike pull-down variants (e.g., LD6815TD/15P), the /15H suffix denotes high-ohmic output disable-no internal discharge path-requiring external circuitry for rapid output discharge. Thermal performance is characterized by R_th(j-a) = 125 K/W on a standard two-layer PCB.

Key Specifications

Pinout & Package

SOT753 (TSOP5) plastic surface-mount package: 2.9 × 1.5 × 1.0 mm, 5-lead, lead pitch 0.95 mm. RoHS-compliant, moisture sensitivity level (MSL) 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LD6815TD/15P, the /15H offers superior isolation in shutdown but requires external discharge; versus XC6215D152MR-G, it delivers 10 dB higher PSRR and 20 µV lower noise at identical load, justifying use in premium audio and imaging subsystems.

Availability

LD6815TD/15H is available at Aetrix Electronics and suitable for smartphones, tablet PCs, and digital still cameras requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LD6815TD/15H 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 headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and consumer markets.

The LD6815 series was designed specifically for ultra-low-noise, high-PSRR power management in portable consumer electronics, targeting noise-sensitive analog and RF subsystems where traditional LDOs fail to meet stringent ripple rejection requirements.

FAQ

What is the output voltage tolerance of the LD6815TD/15H over temperature?

The LD6815TD/15H guarantees output voltage variation of ±3% over the full operating ambient temperature range (−40 °C to +85 °C) at 1 mA load. At 25 °C, the tolerance tightens to ±0.5% typical, ensuring reliable operation for precision analog circuits powered by LD6815TD/15H.

Does the LD6815TD/15H require an external capacitor on the EN pin?

No, the LD6815TD/15H does not require an external capacitor on the EN pin. The enable input is CMOS-compatible with VIH ≥ 1.1 V and VIL ≤ 0.4 V; it draws negligible current and may be driven directly from GPIO or logic outputs. Capacitive filtering is unnecessary unless noise immunity in harsh EMI environments is required-LD6815TD/15H itself provides no internal EN pin filtering.

Can the LD6815TD/15H be used with ceramic output capacitors smaller than 1 µF?

Yes-the LD6815TD/15H is stable with output capacitance as low as 0.7 µF (X7R, ±30% tolerance). While 1 µF is recommended for optimal transient response and PSRR, the minimum 0.7 µF value allows design flexibility in space-constrained layouts. Using capacitors below 0.7 µF risks instability and degraded regulation-LD6815TD/15H must not operate outside this limit.

What is the maximum allowable input voltage for the LD6815TD/15H?

The absolute maximum input voltage for the LD6815TD/15H is +6.0 V for transients up to 4 ms. For continuous operation, the recommended input voltage range is 2.3 V to 5.5 V. Exceeding 5.5 V continuously risks thermal overstress and accelerated parametric drift; operation above 6.0 V-even briefly-may cause permanent damage. Always verify input rail margins before deploying LD6815TD/15H.

How does the high-ohmic disable mode of the LD6815TD/15H affect system power sequencing?

The LD6815TD/15H enters true high-ohmic (3-state) output disable when EN is pulled LOW, disconnecting the output from both the pass transistor and ground. This prevents backfeeding into the LDO and allows independent control of downstream circuitry-critical for safe multi-rail sequencing. Unlike pull-down variants, LD6815TD/15H requires external discharge paths if rapid VOUT decay is needed, preserving isolation integrity.