onsemi NCP500SQL28T1G

Overview

NCP500SQL28T1G from onsemi is a fixed-output, low-noise, low-dropout linear regulator (LDO) designed for noise-sensitive portable applications. It delivers 150 mA output with 2.8 V nominal output voltage, ultra-low 170 mV dropout at full load, 50 µV_RMS output noise (10 Hz–100 kHz, no bypass capacitor), and fast 20 µs enable turn-on time. It operates from 1.8 V to 6.0 V input and supports direct 1.0 V logic enable - ideal for RF stages and post-regulation in battery-powered instrumentation.

For engineers reviewing the NCP500SQL28T1G datasheet, pinout, applications, or equivalent options, key selection criteria include its DFN 2×2.2 mm package, guaranteed ±2.5% output accuracy over −40°C to +85°C, thermal shutdown and current limit protection, and compatibility with low-ESR ceramic output capacitors ≥1.0 µF.

Technical Context

The NCP500SQL28T1G employs a PMOS pass transistor architecture enabling ultra-low dropout and eliminating the need for an external noise-bypass capacitor. Its internal reference, error amplifier, and protection circuits (current limit and thermal shutdown) are integrated into a single die optimized for stability with 1.0 µF ceramic output capacitance.

It features rail-to-rail enable functionality with logic-high threshold of 0.9 V and logic-low threshold of 0.15 V, allowing direct interfacing with low-voltage microcontrollers. The device maintains excellent line regulation (≤10 mV) and load regulation (≤45 mV) across its operating range, supporting precise voltage delivery in dynamic load environments.

Key Specifications

Pinout & Package

Package: DFN 2×2.2 mm (Case 506BA), thermally enhanced with exposed pad (pin 6 = GND). Compact footprint suits space-constrained portable designs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700-2802E/TO and XC6206P282MR-G, the NCP500SQL28T1G offers superior dropout performance in DFN form factor, integrated enable with 1.0 V logic compatibility, and comprehensive protection - making it optimal for compact, battery-efficient, and noise-critical designs.

Availability

NCP500SQL28T1G is available at Aetrix Electronics and suitable for RF power amplifiers, VCO biasing, portable medical sensors, and industrial handheld meters requiring stable component supply, long-term lifecycle support, and Pb-free compliance.

Supply support for NCP500SQL28T1G 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 part of onsemi's precision analog portfolio, engineered specifically for portable and noise-sensitive systems requiring ultra-low dropout, low quiescent current, and no-bypass low-noise regulation.

FAQ

What is the maximum input voltage rating for the NCP500SQL28T1G?

The NCP500SQL28T1G has an absolute maximum input voltage rating of 6.0 V. Operation above this level risks permanent damage. For inputs exceeding 6.0 V (e.g., 12 V rails), an external pre-regulator stage is required - as documented in Figure 34 of the official datasheet. The device is rated for continuous operation from 1.8 V to 6.0 V.

Does the NCP500SQL28T1G require an external bypass capacitor for low-noise performance?

No, the NCP500SQL28T1G does not require an external bypass capacitor. Its proprietary low-noise architecture achieves 50 µV_RMS output noise (10 Hz–100 kHz) without one - a key differentiator versus conventional LDOs. This simplifies layout, reduces BOM count, and avoids startup delays associated with bypass cap charging.

What is the thermal shutdown threshold of the NCP500SQL28T1G?

The NCP500SQL28T1G incorporates internal thermal shutdown that activates at approximately 160°C junction temperature. Once triggered, the regulator disables output until junction temperature falls below the hysteresis threshold (~140°C). This protects the device during sustained overload or poor PCB thermal design - critical for reliability in sealed or high-ambient environments.

Can the NCP500SQL28T1G be used with ceramic output capacitors?

Yes, the NCP500SQL28T1G is fully stable with ceramic output capacitors ≥1.0 µF and exhibits no minimum ESR requirement. This eliminates dependency on tantalum or aluminum electrolytic capacitors, enabling smaller footprints, longer lifetimes, and improved reliability - especially important in portable and automotive-grade designs.

What is the recommended PCB layout practice for the exposed thermal pad on the NCP500SQL28T1G DFN package?

The exposed pad (pin 6) of the NCP500SQL28T1G DFN package must be soldered to a dedicated PCB thermal pad connected to a solid GND plane. Use ≥4 thermal vias (0.3 mm diameter) under the pad to transfer heat to inner or bottom-layer copper. Insufficient thermal relief increases junction temperature rise - limiting max power dissipation to ~400 mW at 25°C ambient.