onsemi NCP603SN250T1G

Overview

NCP603SN250T1G from onsemi is a fixed-output 2.5 V, 300 mA low-dropout (LDO) linear regulator in TSOP-5 package, designed for portable battery-powered systems requiring low noise (50 µV_rms), fast enable response (15 µs), and high PSRR (62 dB at 120 Hz). It operates from 1.75 V to 6 V input and delivers stable regulation across −40 °C to 125 °C ambient.

For engineers reviewing the NCP603SN250T1G datasheet, pinout, applications, or equivalent options, key selection criteria include dropout voltage at 300 mA (max 175 mV @ 2.5 V), ±2% output tolerance over temperature, thermal shutdown (175 °C), ESD robustness (HBM 3.5 kV), and compatibility with low-ESR ceramic capacitors without stability constraints.

Technical Context

The NCP603SN250T1G implements a CMOS-based LDO architecture with internal PNP pass transistor, enabling ultra-low quiescent current (145 µA typical) and minimal dropout. Its enable input features logic-compatible thresholds (0.9 V high, 0.4 V low) and sub-100 nA bias current, supporting precise power sequencing.

It integrates thermal shutdown with 10 °C hysteresis and current limiting (650 mA typical), and achieves 50 µV_rms output noise without bypass capacitor-enabled by proprietary noise-suppression circuitry-not requiring external filtering for RF-sensitive loads like VCOs or ADCs.

Key Specifications

Pinout & Package

Package: TSOP-5 (Case 483), 3.00 mm × 1.50 mm × 0.95 mm, Pb-free, moisture sensitivity level MSL1/260.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP1700T-2502E/MB and TLS850B2TE/V1, the NCP603SN250T1G offers superior noise performance (50 µV_rms vs. 90 µV_rms) and faster enable (15 µs vs. 40 µs), making it optimal for portable RF and precision analog applications where size, noise, and speed outweigh ultra-low IQ or automotive qualification needs.

Availability

NCP603SN250T1G is available at Aetrix Electronics and suitable for SMPS post-regulation, noise-sensitive RF circuits, and portable computing core logic requiring stable component supply, consistent parametric performance, and long-term production continuity.

Supply support for NCP603SN250T1G 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 focused on energy-efficient electronics, delivering silicon solutions for automotive, industrial, cloud, and IoT applications.

The NCP603 series belongs to onsemi's high-performance analog power management portfolio, engineered specifically for portable and battery-constrained systems demanding low noise, fast enable, and robust thermal behavior in miniature packages.

FAQ

What is the maximum input voltage rating for the NCP603SN250T1G?

The NCP603SN250T1G has an absolute maximum input voltage rating of 6.5 V. However, its recommended operating input voltage range is 1.75 V to 6.0 V. Operation above 6.0 V risks exceeding safe power dissipation limits and may trigger thermal shutdown under load. The minimum input voltage depends on output load: for 300 mA at 2.5 V output, Vin must be ≥2.675 V (2.5 V + 175 mV dropout).

Does the NCP603SN250T1G require an external bypass capacitor for noise reduction?

No, the NCP603SN250T1G does not require an external bypass capacitor for noise reduction. Its internal design achieves 50 µV_rms output noise (10 Hz–100 kHz) without any additional capacitor. This eliminates layout complexity and potential resonance issues associated with external RC networks-particularly beneficial in RF and precision analog applications where the NCP603SN250T1G is commonly deployed.

What is the function of Pin 4 (ADJ/NC) on the NCP603SN250T1G?

Pin 4 on the NCP603SN250T1G is marked NC (No Connection) because it is a fixed-output variant. Unlike the adjustable versions (e.g., NCP603SNADJT1G), this pin has no internal connection and must remain unconnected on the PCB. It is not a floating node-no trace should terminate at or route to Pin 4, as confirmed in the datasheet's PIN FUNCTION DESCRIPTION table and MARKING DIAGRAM notes.

How does thermal shutdown operate in the NCP603SN250T1G?

The NCP603SN250T1G incorporates thermal shutdown that activates at approximately 175 °C junction temperature and includes 10 °C hysteresis. When triggered, the regulator disables output and draws only ≤1.0 µA (disable current). Recovery occurs automatically once the junction cools below ~165 °C. This protects against permanent damage during sustained overload, poor PCB heatsinking, or high ambient conditions-critical for sealed portable enclosures where the NCP603SN250T1G is often used.

Can the NCP603SN250T1G be used with ceramic output capacitors?

Yes, the NCP603SN250T1G is fully compatible with ceramic output capacitors and does not require a minimum ESR for stability. The datasheet explicitly states it works with "low cost ceramic capacitors" and provides stability data across 1.0 µF to 10 µF values. A 1.0 µF X7R ceramic capacitor placed close to Pins 2 (GND) and 5 (VOUT) meets all stability and transient response requirements-simplifying BOM and reducing footprint versus tantalum alternatives.