onsemi MC33761SNT1-025G

Overview

MC33761SNT1-025G from onsemi is an ultra-low-noise, low-dropout linear regulator delivering 2.5 V output at up to 80 mA continuous current with 90 mV dropout at 30 mA, 40 µV_RMS integrated noise (100 Hz–100 kHz), and 1.5% output accuracy at 25°C - designed for RF-sensitive portable systems requiring fast wake-up and stable biasing of VCOs and LNA stages.

For engineers reviewing the MC33761SNT1-025G datasheet, pinout, applications, or equivalent options, key selection criteria include its 40 µs ON-to-ON response time at 200 Hz repetition, 1.0 V logic-compatible ON/OFF control, absence of external bypass capacitor requirement, and thermal shutdown protection at 125°C.

Technical Context

The MC33761SNT1-025G employs a proprietary PNP pass transistor architecture with internal bandgap reference and adaptive load-transient improvement circuitry that actively suppresses undershoot during burst-mode load transitions - critical in TDMA-based RF transceivers. Its noise performance is achieved without external bypass capacitance due to optimized internal compensation and low-noise reference design.

It features 1.0 V logic-level ON/OFF control (900 mV threshold), operates from −40°C to +85°C, supports input voltages up to 12 V, and maintains stability with 1.0 µF ceramic or tantalum output capacitors across ESR range 0–3 Ω - eliminating ESR dependency typical of conventional LDOs.

Key Specifications

Pinout & Package

Housed in a Pb-free Thin SOT-23-5 (Case 483, SN suffix) package measuring 2.9 mm × 1.6 mm × 1.1 mm, the MC33761SNT1-025G uses a standard 5-pin layout with exposed pad not electrically connected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A2025PDQNR and NCP1117ST25T3G, the MC33761SNT1-025G uniquely combines 40 µs wake-up, 40 µV_RMS noise without bypass cap, and active load transient suppression - making it irreplaceable in burst-mode RF and portable precision analog systems where timing, noise, and dynamic response are co-constrained.

Availability

MC33761SNT1-025G is available at Aetrix Electronics and suitable for TDMA transceivers, VCO biasing, battery-powered IoT nodes, low-power audio codecs, and other applications requiring stable component supply with guaranteed long-term manufacturability and Pb-free compliance.

Supply support for MC33761SNT1-025G 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 IoT applications - with leadership in analog, power management, and sensing technologies.

The MC33761SNT1-025G belongs to onsemi's ultra-low-noise LDO family engineered specifically for RF and portable systems demanding simultaneous low noise, fast transient response, and minimal external components - targeting VCOs, LNAs, and precision analog signal chains.

FAQ

What is the maximum input voltage rating for the MC33761SNT1-025G?

The MC33761SNT1-025G supports a maximum input voltage of 12 V on the Vin pin, as specified in the Absolute Maximum Ratings table. Operation above this level risks permanent damage. For reliable long-term use, input voltage should remain within Vout + 1.0 V to 12 V - i.e., 3.5 V to 12 V for the 2.5 V output version. The device includes internal protection against overvoltage stress on the input rail.

Does the MC33761SNT1-025G require an external bypass capacitor for noise reduction?

No, the MC33761SNT1-025G does not require an external bypass capacitor. Its proprietary low-noise architecture achieves 40 µV_RMS (100 Hz–100 kHz) and 150 nV/√Hz spectral density without any external capacitor - unlike conventional LDOs that rely on 10–100 nF bypass caps. This eliminates associated start-up delay, board space, and component cost while maintaining RF-grade noise performance.

What is the function of Pin 4 (NC) on the MC33761SNT1-025G?

Pin 4 of the MC33761SNT1-025G is designated NC (No Connect) and is not internally bonded. It must remain unconnected and left floating - neither tied to GND, Vin, nor Vout. This pin exists for mechanical compatibility and potential future variants; connecting it may cause unpredictable behavior or violate the device's thermal and electrical specifications.

How does the MC33761SNT1-025G achieve fast 40 µs wake-up time?

The MC33761SNT1-025G achieves 40 µs typical wake-up time (at 200 Hz repetition rate) by eliminating the external bypass capacitor required by most LDOs. In conventional designs, charging that capacitor dominates start-up latency. The MC33761SNT1-025G's internal architecture delivers full regulation within 40 µs after the ON/OFF pin rises above 900 mV - verified under load conditions of 50 mA and 1.0 µF output capacitance.

Is the MC33761SNT1-025G compatible with ceramic output capacitors?

Yes, the MC33761SNT1-025G is fully compatible with ceramic output capacitors - including X5R and X7R types - and requires only 1.0 µF minimum capacitance. Its ESR-insensitive design accepts output capacitors with ESR ranging from near-zero up to 3 Ω, removing the need for specialized high-ESR tantalum or aluminum electrolytic capacitors traditionally mandated for LDO stability.