onsemi FR015L3EZ

Overview

FR015L3EZ from onsemi is a low-side reverse polarity protection switch designed to block −20 V reverse bias events while delivering 15 mΩ typical on-resistance at 3.0 V, nano-second response time, and integrated TVS clamping - deployed in USB VBUS, battery-powered medical devices, and mobile electronics for fault-tolerant power path control.

For engineers reviewing the FR015L3EZ datasheet, pinout, applications, or equivalent options, this page delivers verified specifications, validated package mapping (WDFN6 2×2 mm), confirmed circuit role as a controlled-series MOSFET switch with startup diode and inrush reduction, and two field-validated alternative parts for reverse-bias protection design-in.

Technical Context

The FR015L3EZ implements a controlled low-side N-channel MOSFET switch with integrated startup diode, inrush current limiter, and bidirectional TVS between CTL and POS pins. It operates only when CTL is biased positively relative to NEG, enabling turn-on at ≥1.5 V and blocking reverse voltage within ≤50 ns.

Its thermal design relies on the WDFN6 2×2 mm package's 60 °C/W junction-to-ambient resistance (on 1 in² 2-oz copper), and its protection behavior is defined by three distinct operating states: normal forward conduction (low R_ON), reverse-bias high-impedance blocking (≤1 µA leakage at −16 V), and integrated TVS clamping (12–14.5 V breakdown, ≤15 V clamping).

Key Specifications

Pinout & Package

FR015L3EZ is housed in a WDFN6 2×2 mm, 0.65 mm pitch, dual-row molded leadless package (Case 511CZ), with exposed thermal pad for enhanced heat transfer and no leadframe plating requirements.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar reverse-bias protection applications.

Compared with TPD3S014TDSR and MAX16050ATA+, the FR015L3EZ offers the fastest response (≤50 ns), smallest footprint (2×2 mm), and lowest turn-on voltage (1.0 V typ), making it optimal for space-constrained, low-voltage battery systems where inrush reduction and minimal voltage drop are critical.

Availability

FR015L3EZ is available at Aetrix Electronics and suitable for USB charging circuits, reverse battery protection, and mobile medical devices requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for FR015L3EZ 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 (Semiconductor Components Industries, LLC) is a global supplier of energy-efficient semiconductor solutions, specializing in power management, protection, and sensing technologies for automotive, industrial, and consumer markets.

The FR015L3EZ belongs to onsemi's FR family of reverse-bias protectors - engineered specifically to replace bulky diode-based solutions with monolithic, low-R_ON, fast-response switches for battery-powered and USB-connected electronics.

FAQ

What is the minimum input voltage required to turn on the FR015L3EZ?

The FR015L3EZ has a typical turn-on threshold (V_ON) of 1.0 V at 100 mA load, with guaranteed operation down to 0.7 V minimum. This allows reliable activation from single-cell alkaline (1.5 V), NiMH (1.2 V), or depleted Li-ion (≥2.5 V) sources. The FR015L3EZ achieves this using an internal charge pump and startup diode, eliminating external bias components.

How does the FR015L3EZ handle reverse polarity events compared to a standard Schottky diode?

Unlike a Schottky diode, which conducts reverse current until destroyed, the FR015L3EZ actively blocks reverse voltage with ≤1 µA leakage at −16 V and responds in ≤50 ns. It also avoids the 0.3–0.4 V forward drop of diodes - delivering only 1.5 mV drop at 0.1 A - and integrates TVS clamping, eliminating four external components typically needed in diode-based designs.

Can the FR015L3EZ be used in USB 3.0 VBUS applications?

Yes - the FR015L3EZ is explicitly rated for USB VBUS compatibility in its datasheet, supporting 5 V nominal operation, ±20 V reverse transients, and IEC61000-4-2 ESD (±7 kV air, ±5 kV contact). Its 15 mΩ R_ON ensures <25 mV drop at 1.5 A, well within USB 3.0 voltage tolerance limits, and its 2×2 mm WDFN6 package fits tight layout constraints near connectors.

What is the role of the CTL pin in the FR015L3EZ?

The CTL pin is the control gate input of the FR015L3EZ's internal MOSFET. When biased positively relative to NEG (e.g., CTL = +3 V, NEG = 0 V), the switch turns ON; when CTL ≤ NEG, the device enters high-impedance blocking mode. This enables system-level control - such as disabling power during firmware updates - and eliminates the need for external gate drivers or level shifters in the FR015L3EZ design.

Does the FR015L3EZ require external capacitors or resistors for basic operation?

No - the FR015L3EZ operates stand-alone with only three connections: POS, NEG, and CTL. Its integrated startup diode, inrush reducer, and TVS eliminate the need for external bypass caps, gate resistors, or clamping diodes. Layout best practices recommend keeping traces short and using the recommended 2×2 mm land pattern (Option 1 or 2 per datasheet), but no active external components are required for functional reverse-bias protection.