onsemi NUS2045MNT1

Overview

NUS2045MNT1 from onsemi is an overvoltage protection IC with integrated −20 V P-channel MOSFET, designed for input-side fault protection in portable power systems. It features a nominal 6.85 V overvoltage threshold, 71 mΩ R_DS(on) at −4.5 V, undervoltage lockout at 2.8 V, and logic-compatible control input-enabling robust battery and system protection in single-cell Li-ion and 3/4-cell NiMH/NiCd applications.

For engineers reviewing the NUS2045MNT1 datasheet, pinout, applications, or equivalent options, this page delivers verified electrical parameters, DFN8 package layout, truth-table–driven control behavior, thermal limits (T_J = 150°C), and real-world alternative options for overvoltage-protected power path design.

Technical Context

The NUS2045MNT1 integrates an NCP345-based OVP controller with a monolithic −20 V P-channel MOSFET in a single DFN8 package. Its dual-input protection logic responds independently to overvoltage on IN (6.85 V threshold) and undervoltage on VCC (2.8 V lockout), driving OUT to disconnect the FET within ≤1.0 µs under overvoltage conditions.

Control is implemented via CNTRL pin compatibility with 1.8 V logic, while internal gate driver ensures fast turn-on/off delays (TON IN ≤10 µs, TOFF IN ≤1.0 µs at C_L = 12 nF). The device operates across −40°C to +85°C ambient and supports Pb-free reflow up to 235°C.

Key Specifications

Pinout & Package

Package: 3.3 × 3.3 mm, 0.9 mm height, 8-pin DFN (Case 506AL), exposed thermal pad, Pb-free MNT1 suffix rated for 235°C reflow.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overvoltage protection applications.

Compared with TPS259211DRCT and NCP345MUTAG, the NUS2045MNT1 provides the smallest footprint and lowest component count for fixed-threshold, ≤1 A overvoltage protection-making it optimal for ultra-compact portable devices where board area and supply-chain simplicity are critical.

Availability

NUS2045MNT1 is available at Aetrix Electronics and suitable for portable computers and PDAs, cell phones and handheld products, and digital cameras requiring stable component supply with guaranteed long-term sourcing and consistent DFN8 packaging.

Supply support for NUS2045MNT1 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, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The NUS2045MNT1 belongs to onsemi's Overvoltage Protection IC product line, engineered specifically to simplify input-stage safety in portable electronics powered by unregulated AC-DC adapters or automotive chargers.

FAQ

What is the maximum continuous drain current supported by the NUS2045MNT1?

The NUS2045MNT1 supports a continuous drain current of −1.0 A at T_A = 25°C, as specified in its Absolute Maximum Ratings table. This rating assumes proper PCB thermal design with a 1-inch² copper pad. At elevated ambient temperatures or reduced copper area, derating is required per the 104.3°C/W R_θJA value. The NUS2045MNT1 is not rated for pulsed or surge currents beyond this steady-state limit.

Does the NUS2045MNT1 require an external capacitor on the VCC pin?

Yes, the NUS2045MNT1 requires a minimum 1 µF ceramic capacitor placed as close as possible to the VCC (pin 8) and GND pins. This capacitor stabilizes the internal regulator and ensures reliable UVLO operation and fast OVP response. The datasheet specifies this as mandatory for all operating conditions, and omission may cause erratic turn-on behavior or delayed fault response in the NUS2045MNT1.

Can the overvoltage threshold of the NUS2045MNT1 be adjusted above 6.85 V?

Yes, the NUS2045MNT1's overvoltage threshold can be increased using an external resistor divider between IN (pin 1) and VCC (pin 8). The internal reference is fixed, but the external network scales the sensed voltage. The datasheet provides design equations and examples for setting thresholds up to ~12 V. However, the NUS2045MNT1's absolute maximum IN voltage remains 30 V, limiting practical adjustment range.

Is the NUS2045MNT1 pin-compatible with the NUS3045MNT1?

No, the NUS2045MNT1 and NUS3045MNT1 share identical pinout and package (DFN8, Case 506AL), but they are not functionally interchangeable without validation. While both have the same footprint and control logic, the NUS3045MNT1 integrates a −30 V MOSFET with 66 mΩ R_DS(on), whereas the NUS2045MNT1 uses a −20 V MOSFET with 71 mΩ R_DS(on). Substitution requires confirming voltage stress margins and thermal performance in the target application.

What is the purpose of the exposed thermal pad on the NUS2045MNT1 DFN8 package?

The exposed thermal pad on the bottom of the NUS2045MNT1 DFN8 package must be soldered to a PCB thermal pad to achieve the specified 104.3°C/W junction-to-air thermal resistance. It serves as the primary heat conduction path from the integrated MOSFET die to the board. Leaving it unconnected or floating degrades thermal performance significantly, risking thermal shutdown or premature failure under sustained 1 A load in the NUS2045MNT1.