Renesas IW3636-31

Overview

The IW3636-31 from Renesas Electronics is a single-stage AC/DC LED driver IC with integrated power factor correction (PFC), designed for PWM-dimmable lighting systems. It delivers ±3% output current regulation via primary-side sensing, supports 1–100% dimming range, operates in quasi-resonant mode at 72 kHz or 90 kHz, and accepts analog dimming on the NTC/DIM2 pin-specifically configured with internal OTP disabled per ordering code.

For engineers reviewing the IW3636-31 datasheet, IW3636-31 pinout, IW3636-31 application, or IW3636-31 equivalent, key selection considerations include its SOIC-8 package, dual-dimming interface support (PWM + analog), active start-up scheme, built-in fault protections (OVP, OCP, UVP, OTP), and compatibility with Renesas iW339 for optocoupler-free 0–10V dimming.

Technical Context

The IW3636-31 implements constant-on-time control with PrimAccurate™ primary-side regulation to achieve >0.9 PF and <20% THD across wide load ranges without secondary feedback. Its adaptive frequency control eliminates audible noise while maintaining efficiency across dimming levels.

It integrates multi-function pins (NTC/DIM2 and VSENSE) for configuration of dimming curve (linear/logarithmic), minimum dimming level (dim-to-off, 1%, 5%, or 10%), and startup behavior. The IC supports both enhancement- and depletion-mode FETs for active start-up and features light-off mode with configurable voltage regulation.

Key Specifications

Pinout & Package

Package: 8-lead SOIC-8 (surface-mount, standard footprint, θ_JA = 170°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with NCL30086 and ICE2QS03G, the IW3636-31 uniquely integrates single-stage PFC, analog+PWM dimming, and primary-side regulation in SOIC-8-enabling smaller form factors, lower component count, and tighter dimming performance for mid-power (<90 W) commercial lighting.

Availability

IW3636-31 is available at Aetrix Electronics and suitable for intelligent wireless LED luminaires, commercial 0–10V dimmable ballasts, industrial tunable-white drivers, and architectural LED retrofit kits requiring stable component supply and long-term production continuity.

Supply support for IW3636-31 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 products for automotive, industrial, infrastructure, and IoT applications.

The IW3636-31 belongs to Renesas' Intelligent Lighting Solutions product line, engineered specifically for high-efficiency, digitally controllable LED drivers that eliminate secondary feedback while meeting global energy and dimming standards.

FAQ

What dimming interfaces does the IW3636-31 support?

The IW3636-31 supports dual dimming interfaces: a dedicated PWM input on DIM1 pin and analog voltage input (0–1.8 V) on the NTC/DIM2 pin. Unlike variants with OTP enabled, the IW3636-31 has internal OTP disabled-allowing field-programmable configuration of dimming curve and minimum dimming level via external resistor networks on VSENSE and NTC/DIM2 pins. This enables flexible integration with 0–10V controllers, MCUs, or wireless modules without firmware updates.

How does the IW3636-31 achieve power factor correction without a separate PFC controller?

The IW3636-31 implements single-stage PFC using constant-on-time quasi-resonant control, directly shaping input current to match the AC line voltage waveform. It achieves >0.9 PF and <20% THD across full load range by dynamically adjusting switching frequency and conduction timing based on line voltage (VIN pin) and output regulation error. This eliminates the need for a dedicated boost PFC stage, reducing component count, size, and cost versus two-stage solutions.

What protection features are integrated into the IW3636-31?

The IW3636-31 includes built-in single-point fault protections: output open-circuit, output short-circuit, output over-voltage, input under-voltage, and over-temperature (via internal sensor or external NTC on NTC/DIM2 pin). All protections trigger automatic latch-off or hiccup mode with auto-restart. These functions operate independently of external components, ensuring robust system reliability without added discrete protection circuitry.

Can the IW3636-31 be used with the iW339 interface controller?

Yes-the IW3636-31 is fully compatible with Renesas' iW339 secondary-side PWM signal generator. When paired, the IW3636-31 uses a proprietary technique to compensate for optocoupler non-idealities (e.g., CTR drift, delay), enabling accurate 0–10V dimming without secondary feedback. The iW339 drives the DIM1 pin of IW3636-31, while IW3636-31's NTC/DIM2 pin remains available for analog current scaling or temperature derating-preserving full dual-interface capability.

What is the significance of "Internal OTP Disabled" in the IW3636-31 ordering code?

"Internal OTP Disabled" means the one-time-programmable memory used to fix configuration parameters (e.g., dimming curve, min dim level, frequency) during factory programming is disabled in the IW3636-31. This allows end users to configure those settings dynamically via external resistor dividers on VSENSE and NTC/DIM2 pins-enabling field tuning, multiple SKU consolidation, and rapid prototyping without custom mask revisions. All other electrical and functional specs match the base iW3636 family.