onsemi NCP120BMX120TCG

Overview

NCP120BMX120TCG from onsemi is a 150 mA very low dropout (VLDO) CMOS voltage regulator with NMOS pass transistor and separate VBIAS supply, delivering 1.20 V fixed output at ±1.5% accuracy over −40°C to +85°C, 75 mV max dropout at 150 mA, and ultra-low bias current (80 µA typ), designed for noise-sensitive, space-constrained portable applications such as smartphone I/O rails.

For engineers reviewing the NCP120BMX120TCG datasheet, pinout, applications, or equivalent options, key selection criteria include dual-rail operation (VIN/VBIAS), absence of active output discharge, XDFN6 thermal pad grounding requirement, and compatibility with 1 µF ceramic output capacitors in low-voltage post-regulation systems.

Technical Context

The NCP120BMX120TCG implements a dual-input NMOS-based LDO architecture where VIN supplies the pass element and VBIAS powers internal control circuitry independently-enabling stable regulation even when VIN approaches VOUT. Its UVLO monitors VBIAS with 1.6 V threshold and 0.2 V hysteresis, ensuring reliable startup under varying bias conditions.

Unlike PMOS LDOs, this topology decouples output capacitor ESR sensitivity from loop stability and supports monotonic start-up with controlled slew rate. The device lacks active output discharge (distinguishing it from 'A' variants), making it suitable for systems requiring hold-up or controlled power-down sequencing.

Key Specifications

Pinout & Package

The NCP120BMX120TCG is housed in an XDFN6 package (1.2 mm × 1.2 mm × 0.4 mm, Case 711AT) with an exposed thermal pad that must be soldered to the PCB ground plane for thermal performance. Pin 2 is not internally connected.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout voltage regulator applications.

Compared with NCP120AMX120TCG and TPL7407LDR, the NCP120BMX120TCG delivers the lowest dropout (75 mV), best PSRR (80 dB on VBIAS), and smallest footprint (1.2 mm²), making it optimal for space- and noise-constrained single-rail applications where active discharge is unnecessary.

Availability

NCP120BMX120TCG is available at Aetrix Electronics and suitable for smartphone I/O rail regulation, tablet memory interface power, and wearable sensor hub applications requiring stable component supply, consistent marking (J, 270° rotation), and RoHS-compliant XDFN6 packaging.

Supply support for NCP120BMX120TCG 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient silicon solutions for automotive, industrial, cloud, medical, and portable electronics.

The NCP120 product line delivers ultra-low-noise, dual-rail LDOs optimized for post-regulation in battery-powered portable devices where space, thermal limits, and power integrity are critical design constraints.

FAQ

What is the output voltage tolerance of the NCP120BMX120TCG over temperature?

The NCP120BMX120TCG provides a fixed 1.20 V output with ±1.5% accuracy across the full operating junction temperature range of −40°C to +85°C. At 25°C, output voltage accuracy tightens to ±0.5%, as specified in the Electrical Characteristics table. This tolerance ensures reliable operation for precision I/O and memory interface rails without external trimming.

Does the NCP120BMX120TCG include active output discharge functionality?

No, the NCP120BMX120TCG does not include active output discharge. It belongs to the 'B' variant family, which omits the internal discharge FET present in 'A' variants like NCP120AMX120TCG. When disabled via the EN pin, the output floats; external discharge circuitry must be added if rapid VOUT decay is required.

What is the minimum input voltage required for the NCP120BMX120TCG to maintain regulation at 150 mA?

The NCP120BMX120TCG requires a minimum input voltage of 1.275 V to maintain 1.20 V output at 150 mA load, based on its maximum dropout voltage of 75 mV. This allows operation from deeply discharged single-cell Li-ion batteries (down to ~2.6 V system rail) when used with appropriate upstream conversion.

Can the NCP120BMX120TCG operate with only the IN pin powered, without connecting VBIAS?

No, the NCP120BMX120TCG requires both IN and VBIAS to be powered within their respective ranges (VIN: 0.8–5.5 V; VBIAS: 2.4–5.5 V) for normal operation. The VBIAS pin supplies internal control circuitry including the voltage reference and error amplifier; omission or undervoltage on VBIAS triggers UVLO and disables regulation regardless of IN status.

What package type and thermal requirements apply to the NCP120BMX120TCG?

The NCP120BMX120TCG uses the XDFN6 package (1.2 mm × 1.2 mm × 0.4 mm, Case 711AT) with an exposed thermal pad. This pad must be soldered to a PCB ground plane to achieve the specified R_JA of 170 °C/W; failure to do so risks thermal shutdown under 150 mA continuous load due to excessive junction temperature rise.