Renesas IW3658-21F

Overview

The IW3658-21F from Renesas Electronics is a single-stage, phase-cut dimmable SSL LED driver IC with integrated 650V/2A high-voltage MOSFET, designed for 230VAC input retrofit lamps up to 15W. It delivers closed-loop constant current regulation in buck-boost topology, supports leading- and trailing-edge dimmers, and features PrimAccurate™ primary-side sensing for accurate output current control without optocoupler or secondary feedback.

For engineers reviewing the IW3658-21F datasheet, IW3658-21F pinout, IW3658-21F application, or IW3658-21F equivalent, key selection considerations include its 650V HV drain rating, SO-7 package with enhanced creepage, VCC regulation across dimmer phase angles, thermal derating behavior, and compatibility with A/BR/GU/PAR lamp form factors.

Technical Context

The IW3658-21F implements boundary conduction mode (BCM) control with resonant switching to achieve >85% typical efficiency and low EMI. Its patented PrimAccurate™ technology enables precise primary-side current regulation by sampling transformer auxiliary winding voltage and demagnetization timing.

It integrates a 650V/2A MOSFET and proprietary VCC regulation circuit that maintains stable logic supply regardless of LED string voltage or dimmer conduction angle-directly addressing low-end flicker in 230VAC dimming systems. The device operates across 45–66Hz line frequency and includes built-in OVP, OTP, LED open/short protection, and fast start-up (<0.5s).

Key Specifications

Pinout & Package

Package: 7-lead SO (SO-7) with extended creepage between HV drain and low-voltage pins for reinforced isolation in 230VAC applications.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dimmable LED driver applications.

Compared with MP4008GQ-Z and NCP1075P, the IW3658-21F provides superior dimmer interoperability, integrated 650V/2A switching, and flicker-free operation at low dim levels-making it optimal for premium 230VAC retrofit lamps requiring high reliability and minimal bill-of-materials.

Availability

IW3658-21F is available at Aetrix Electronics and suitable for A-style LED bulbs, BR30 retrofit lamps, GU10 spotlights, and PAR30/38 floodlights requiring stable component supply in high-volume 230VAC lighting programs.

Supply support for IW3658-21F 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

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, infrastructure, and IoT applications.

The IW3658-21F belongs to Renesas' Dialog-branded LED driver portfolio, engineered specifically for high-efficiency, flicker-free, single-stage dimmable LED lighting in 230VAC markets.

FAQ

What is the maximum output power supported by the IW3658-21F?

The IW3658-21F supports up to 15W output power in dimmable retrofit lamp designs. However, for outputs above 12W, thermal validation is required to ensure junction temperature remains below 120°C. The device includes built-in thermal derating and over-temperature shutdown to protect against sustained overheating during operation.

Does the IW3658-21F require an external MOSFET?

No, the IW3658-21F integrates a 650V/2A high-voltage MOSFET in its SO-7 package, eliminating the need for an external switch. This integration reduces component count, simplifies PCB layout, and improves reliability in compact 230VAC LED lamp designs-unlike controllers such as NCP1075P that require discrete MOSFETs.

How does the IW3658-21F prevent low-end flicker with TRIAC dimmers?

The IW3658-21F uses a proprietary VCC regulation circuit that maintains stable internal supply voltage across all dimmer phase angles-including near-zero conduction. This prevents logic brown-out and ensures consistent gate drive and current regulation, directly eliminating low-end flicker common in 230VAC dimming systems.

What dimmer types are compatible with the IW3658-21F?

The IW3658-21F supports both leading-edge (R-type and R-L type) and trailing-edge (R-C type) wall dimmers. Its advanced dimming control algorithm adapts to varying dimmer characteristics and line frequencies (45–66Hz), enabling broad compatibility across European and Asian 230VAC residential dimming infrastructures.

What protection features are built into the IW3658-21F?

The IW3658-21F includes LED open-circuit and short-circuit protection, overvoltage protection (OVP) configurable via the CFG pin, over-temperature shutdown, and thermal current derating. These protections operate autonomously without external circuitry, enhancing system safety and field reliability in enclosed lamp housings.