onsemi NCP511SN25T1G

Overview

NCP511SN25T1G from onsemi is a fixed-output, CMOS low-dropout linear regulator delivering 2.5 V at up to 150 mA with ultra-low 40 µA quiescent current and 100 mV dropout voltage at 100 mA. It integrates PMOS pass transistor, thermal shutdown, current limit, and enable control - designed for battery-powered portable electronics requiring stable low-voltage supply under light-load conditions.

For engineers reviewing the NCP511SN25T1G datasheet, pinout, applications, or equivalent options, key selection criteria include its 2.5 V ±2.0% output accuracy, TSOP-5 package compatibility with ceramic capacitors ≥1.0 µF, industrial temperature range (−40°C to +85°C), and enable-controlled standby mode with 0.3 V logic-low disable threshold.

Technical Context

The NCP511SN25T1G employs a PMOS pass transistor architecture enabling low dropout and near-zero ground current increase under load. Its internal error amplifier compares feedback against a precision voltage reference, while protection circuits enforce current limit (200–800 mA depending on input) and thermal shutdown at ~160°C.

Enable functionality provides active-high control with 1.3 V turn-on threshold; unused Enable must be tied to Vin. The device achieves 50 dB ripple rejection at 1 kHz and 110 µV_RMS output noise (20 Hz–100 kHz), supporting noise-sensitive analog and RF subsystems in compact portable designs.

Key Specifications

Pinout & Package

The NCP511SN25T1G is housed in a Pb-free TSOP-5 surface-mount package (3.00 × 1.50 × 0.95 mm, 0.95 mm pitch), optimized for space-constrained portable PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2502E/TT and TCS2115-2.5V, the NCP511SN25T1G offers tighter output accuracy and lower dropout in the same TSOP-5 footprint - making it optimal for space- and precision-constrained portable instrumentation where battery headroom and ADC reference stability are critical.

Availability

NCP511SN25T1G is available at Aetrix Electronics and suitable for wearable health monitors, industrial handheld scanners, smart home sensor nodes, portable test instruments, and battery-powered instrumentation requiring stable component supply with long-lifecycle support.

Supply support for NCP511SN25T1G 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 power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The NCP511SN25T1G belongs to the NCP511 series of ultra-low-I_Q LDO regulators engineered specifically for battery-powered portable equipment where extended runtime and small form factor are essential design constraints.

FAQ

What is the maximum input voltage rating for the NCP511SN25T1G?

The NCP511SN25T1G has an absolute maximum input voltage of 6.0 V. Exceeding this rating risks permanent damage. For inputs above 6.0 V, a pre-regulator stage (e.g., resistive divider with Zener clamp or upstream buck converter) is required - as documented in Figure 22 of the NCP511 datasheet. Operation within 0–6.0 V ensures compliance with all electrical specifications for the NCP511SN25T1G.

Does the NCP511SN25T1G require an external output capacitor, and what type is recommended?

Yes, the NCP511SN25T1G requires a minimum 1.0 µF output capacitor. Ceramic capacitors are fully supported and preferred due to low ESR and size efficiency; tantalum types are also acceptable. The device remains stable with ESR values from a few mΩ up to 3.0 Ω. Larger capacitance improves load transient response and noise filtering - critical for powering sensitive analog circuitry in the NCP511SN25T1G application.

How does the Enable pin function on the NCP511SN25T1G, and what happens when it's left unconnected?

The Enable pin on the NCP511SN25T1G is active-high: output regulates when voltage ≥1.3 V, and disables (high-impedance output, IQ ≤0.1 µA) when ≤0.3 V. If unused, the pin must be connected directly to Vin - floating or open-circuit operation is undefined and may cause erratic regulation or increased quiescent current. This requirement is explicitly stated in the Pin Function Description section for the NCP511SN25T1G.

What is the thermal shutdown behavior of the NCP511SN25T1G, and how does it recover?

The NCP511SN25T1G activates thermal shutdown at approximately 160°C junction temperature, turning off the output until die temperature falls below the hysteresis threshold (~140°C). Recovery is automatic and does not require cycling Enable or input power. During shutdown, ground current drops to near-zero, minimizing further heating. This protection mechanism prevents irreversible damage during sustained overload or inadequate PCB copper area - a key reliability feature of the NCP511SN25T1G.

Is the NCP511SN25T1G suitable for automotive applications, and what qualification does it hold?

The NCP511SN25T1G is not AEC-Q100 qualified. For automotive use, the pin-compatible NCV511SN25T1G variant is specified - it carries the "NCV" prefix, meets AEC-Q100 Grade 1 (−40°C to +125°C), and supports PPAP documentation. The NCP511SN25T1G is rated for industrial temperature (−40°C to +85°C) and intended for consumer, medical, and industrial portable equipment - not under-hood automotive systems. Select NCV511SN25T1G instead for qualified automotive deployment.