Renesas IW3677-00

Overview

The iW3677-00 from Renesas Electronics is a single-stage, primary-side AC/DC PWM controller with integrated PFC for LED lighting drivers up to 100W. It delivers constant voltage (CV) and constant current (CC) regulation with <±3% CV line/load regulation, >0.9 power factor, <20% THD at ≥50% load, and <150mW standby loss at 230VAC - deployed in compact SOIC-7 for flyback/buck-boost topologies.

For engineers reviewing the iW3677-00 datasheet, iW3677-00 pinout, iW3677-00 application, or iW3677-00 equivalent, key selection criteria include primary-side regulation accuracy, integrated HV startup, audible-noise-free transient response, and compliance with universal AC input (90–305VAC) and safety-critical protection requirements.

Technical Context

The iW3677-00 implements digital control using Renesas' PrimAccurate™ architecture to eliminate external loop compensation while maintaining stability across line and load variations. Its PF-Boost™ technology enables active PFC without secondary sensing, achieving >0.9 PF and <20% THD across full AC line range at ≥50% load.

It supports both constant-power (e.g., second-stage DC/DC) and constant-resistance (e.g., LED strips) loads. Integrated high-voltage startup (up to 600V) reduces BOM count and enables sub-0.25s startup time without auxiliary winding or startup resistor.

Key Specifications

Pinout & Package

Package: 7-lead SOIC (Small Outline Integrated Circuit), surface-mount, RoHS-compliant, thermal resistance θ_JA = 100°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side AC/DC controller applications.

Compared with NCP1654 and ICE2PCS01, the iW3677-00 uniquely integrates digital primary-side regulation, HV startup, and comprehensive protection in SOIC-7 - enabling single-stage, low-noise, ultra-low-standby LED drivers without auxiliary components or secondary feedback.

Availability

iW3677-00 is available at Aetrix Electronics and suitable for smart residential lighting, commercial dimmable LED strips, and industrial high-bay drivers requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for iW3677-00 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, and IoT markets - headquartered in Tokyo, Japan.

The iW3677-00 belongs to Renesas' Intelligent Power IC product line, engineered specifically for highly integrated, high-efficiency AC/DC LED driver solutions that eliminate secondary-side feedback and reduce system-level BOM count.

FAQ

What is the primary function of the iW3677-00 in an LED lighting system?

The iW3677-00 serves as a single-stage, primary-side AC/DC controller with integrated PFC for LED drivers up to 100W. It performs simultaneous constant voltage and constant current regulation without secondary-side feedback, using PrimAccurate™ digital control. The iW3677-00 directly senses output voltage and current via transformer reset and current-sense signals, enabling compact, low-cost, and high-reliability LED power supplies compliant with global energy standards.

Does the iW3677-00 require an external startup resistor or auxiliary winding?

No, the iW3677-00 integrates a high-voltage startup circuit rated up to 600V on the HV pin (Pin 4), eliminating the need for an external startup resistor or auxiliary winding. This integration reduces BOM count, improves system reliability, and enables startup in less than 0.25 seconds. The iW3677-00 draws startup current directly from the rectified AC line, simplifying transformer design and lowering overall solution cost.

What protections does the iW3677-00 provide, and how are they implemented?

The iW3677-00 provides output over-voltage, output short-circuit, AC over-voltage, AC under-voltage (brown-out), cycle-by-cycle over-current, current-sense-resistor short, and over-temperature protection. These are implemented internally using dedicated analog comparators and digital logic - no external supervision IC is required. For example, AC UVP/OVP uses the VIN pin, while OTP relies on on-die thermal sensing with automatic latch-off at 150°C junction temperature. The iW3677-00 ensures safe, autonomous operation in unattended LED lighting systems.

Can the iW3677-00 support both constant-voltage and constant-current LED loads?

Yes, the iW3677-00 supports both constant-voltage (CV) and constant-current (CC) modes with independent regulation accuracy: CV regulation is <±3% across line and load, and CC regulation is <±5%. It adapts automatically based on load type - e.g., CV for LED drivers feeding downstream DC/DC converters, and CC for direct LED string driving. The iW3677-00 achieves this using dual-loop digital control and configurable CS/CFG pin settings, making it suitable for diverse LED topology implementations.

What package type and thermal performance does the iW3677-00 use?

The iW3677-00 is housed in a 7-lead SOIC package with θ_JA = 100°C/W, supporting surface-mount assembly and reflow soldering. Its thermal design accommodates continuous operation up to 150°C junction temperature, with derating guidance provided in the datasheet. The exposed pad-less SOIC-7 footprint allows standard PCB routing while maintaining isolation between primary and secondary sides. The iW3677-00's thermal performance enables 100W operation in compact form factors without forced air cooling.