onsemi NCP500SN28T1G

Overview

NCP500SN28T1G from onsemi is a fixed-output, low-noise, low-dropout linear regulator delivering 2.8 V at up to 150 mA. It features an ultra-low dropout voltage of 170 mV at full load, 50 µV RMS noise (10 Hz–100 kHz) without bypass capacitor, and fast 20 µs enable turn-on time. Designed for noise-sensitive RF and portable battery-powered systems, it operates from 1.8 V to 6.0 V input and supports ceramic output capacitors as small as 1.0 µF.

For engineers reviewing the NCP500SN28T1G datasheet, pinout, applications, or equivalent options, key selection criteria include dropout performance under 150 mA load, enable logic compatibility with 1.0 V microcontrollers, thermal shutdown behavior at 160 °C, RMS noise specification in RF post-regulation contexts, and DFN 2×2.2 mm package footprint constraints.

Technical Context

The NCP500SN28T1G uses a PMOS pass transistor architecture enabling ultra-low dropout and eliminating the need for external noise-bypass capacitors. Its internal reference, error amplifier, and protection circuits (current limit and thermal shutdown) are integrated into a single die optimized for stable operation with low-ESR ceramic output capacitors.

It supports direct 1.0 V logic-level enable control with sub-100 nA bias current and a defined threshold (0.9 V high, 0.15 V low), making it compatible with modern low-voltage I/O domains. The device maintains ±2.5% output accuracy across −40 °C to +85 °C and load currents from 1 mA to 150 mA.

Key Specifications

Pinout & Package

Package: DFN 2×2.2 mm, 6-pin, Pb-free, moisture-sensitive level 1 (MSL1).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2802E/TT and TLS850B2TE/V33, the NCP500SN28T1G uniquely balances ultra-low noise (50 µV), 1.0 V enable compatibility, and 170 mV dropout in a 2×2.2 mm DFN - making it optimal for space-constrained, battery-powered RF and precision analog applications where startup speed and noise floor are critical.

Availability

NCP500SN28T1G is available at Aetrix Electronics and suitable for RF front-end biasing, VCO supply regulation, and portable medical sensor powering requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for NCP500SN28T1G 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 is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

The NCP500 series is designed specifically for portable, battery-powered systems demanding low quiescent current, ultra-low noise, and fast enable response - targeting RF, audio, and precision analog subsystems where supply integrity directly impacts signal fidelity.

FAQ

What is the minimum input voltage required for NCP500SN28T1G to maintain regulation at 150 mA load?

The NCP500SN28T1G requires a minimum input voltage of 2.97 V to maintain 2.8 V output regulation at 150 mA, based on its 170 mV dropout voltage (V_in = V_out + V_dropout = 2.8 V + 0.17 V). This allows reliable operation down to end-of-discharge voltage of single-cell Li-ion batteries. The device remains functional but unregulated below this threshold.

Does NCP500SN28T1G require an external noise-bypass capacitor?

No, the NCP500SN28T1G does not require an external noise-bypass capacitor. Its internal low-noise architecture achieves 50 µV RMS output noise (10 Hz–100 kHz) without one - confirmed in the datasheet's "Typical RMS Noise Voltage" specification. Adding a bypass capacitor may degrade the 20 µs enable turn-on time and is unnecessary for noise compliance.

Can NCP500SN28T1G be used with a 1.0 V microcontroller GPIO to control enable?

Yes, NCP500SN28T1G is explicitly designed for 1.0 V logic compatibility: its enable threshold is guaranteed at ≥0.9 V for turn-on and ≤0.15 V for turn-off, with input bias current as low as 3.0 nA typical. This allows direct connection to 1.0 V I/O pins without level-shifting circuitry - a key differentiator versus most competing LDOs.

What is the thermal shutdown temperature of NCP500SN28T1G?

The NCP500SN28T1G incorporates internal thermal shutdown that activates at approximately 160 °C junction temperature, as stated in the datasheet's "Definitions" section. Once triggered, the regulator disables output until junction temperature falls below the hysteresis threshold (~140 °C), protecting against permanent damage during sustained overload or poor PCB thermal design.

Is NCP500SN28T1G compatible with ceramic output capacitors smaller than 1.0 µF?

No - the NCP500SN28T1G requires a minimum output capacitance of 1.0 µF, as specified in the datasheet's "Typical Applications" and "Applications Information" sections. Using smaller values risks instability, excessive load transient overshoot, and degraded ripple rejection. Ceramic capacitors are fully supported and recommended due to their low ESR and stability.