Renesas IW1796-08

Overview

The IW1796-08 from Renesas Electronics is a high-performance AC/DC primary-side PWM controller for rapid charge adapters, supporting XM-Comm transformer-based communication with iW662-05/08 secondary-side controllers. It delivers multi-level constant voltage (up to 21V) and constant current regulation without optocoupler or secondary feedback, achieves <75mW no-load power at 230VAC/5VOUT, and operates in quasi-resonant mode for high efficiency in ≥45W designs.

For engineers reviewing the IW1796-08 datasheet, IW1796-08 pinout, IW1796-08 application, or IW1796-08 equivalent, key selection considerations include XM-Comm protocol compatibility with QC2.0/QC3.0, primary-side CV/CC regulation accuracy, no-load power performance, VCC pin voltage rating (−0.3 to 45.0 V), and SOT23-6 package thermal resistance (θ_JA = 208 °C/W).

Technical Context

The IW1796-08 implements proprietary XM-Comm technology to enable bidirectional transformer-coupled communication-transmitting output voltage requests, current limits, and OVP/undershoot data from iW662-05/08 to the primary side without optocouplers or auxiliary windings. Its quasi-resonant PWM architecture adapts switching frequency dynamically based on load and line conditions.

It integrates RC-charging VCC startup for ultra-low standby power and supports user-configurable 4-level cable drop compensation independent of output voltage. Built-in fault protection includes soft-short detection, half-short recovery, and over-temperature shutdown with internal OTP control-no latch required.

Key Specifications

Pinout & Package

The IW1796-08 is housed in a 6-lead SOT23-6 package with exposed pad for thermal enhancement. Pin 1 (VCC) accepts up to 45 V DC input; Pin 2 (VSENSE) serves dual role for auxiliary winding sensing and XM-Comm signal demodulation; Pin 4 (CS/CDC) provides cycle-by-cycle current sensing and cable drop compensation configuration; Pin 6 (GATE) drives external MOSFET with −0.3 V to 30 V swing.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar primary-side rapid charge controller applications.

Compared with MP6908A and INN3377C, the IW1796-08 uniquely enables optocoupler-free, transformer-coupled rapid charge control with full primary-side CV/CC regulation-reducing component count by ≥4 parts and eliminating loop compensation while maintaining <75mW no-load power and 21V output capability.

Availability

The IW1796-08 is available at Aetrix Electronics and suitable for smartphone rapid charging adapters, tablet wall chargers, and USB-C power delivery accessories requiring stable component supply, consistent XM-Comm protocol support, and compliance with global energy efficiency standards.

Supply support for IW1796-08 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 Corporation is a global semiconductor leader delivering microcontrollers, analog, power, and SoC products for automotive, industrial, infrastructure, and IoT applications.

The IW1796-08 belongs to Renesas' Rapid Charge™ controller family, engineered specifically for high-efficiency, optocoupler-free AC/DC adapters supporting Qualcomm Quick Charge 2.0/3.0 and other proprietary fast-charge protocols.

FAQ

What is the default constant-current gain (kCC) setting for IW1796-08 at startup?

The IW1796-08 has a factory-programmed default k_CC value of 0.422 at startup, as specified in the Ordering Information table. This value determines the current-sense-to-control-loop gain and is fixed for this variant-no external resistor or configuration is required to set it. The IW1796-08 maintains this k_CC across all operating conditions unless modified via XM-Comm command from the iW662-05/08 secondary controller.

Does IW1796-08 require an external MOSFET, and what gate drive capability does it provide?

Yes, the IW1796-08 requires an external high-voltage MOSFET, driven via its dedicated GATE pin (Pin 6). The IW1796-08 provides rail-to-rail gate drive output with −0.3 V to 30 V swing and sufficient peak current to drive typical 1 Ω gate impedance at switching frequencies up to 130 kHz. It does not integrate a power switch, enabling flexible selection of optimized MOSFETs for specific power and thermal targets.

How does IW1796-08 achieve <75mW no-load power without an active startup circuit?

The IW1796-08 achieves <75mW no-load power using an integrated RC-charging VCC circuit that draws minimal current from the auxiliary winding during light/no-load conditions. This architecture eliminates the need for a dedicated active start-up circuit in basic implementations. The IW1796-08 datasheet confirms this performance at 230VAC/5VOUT with ample margin, and further reduction to <20mW is possible only when adding an external DFET-based active startup stage.

Which secondary-side controller is specifically matched to IW1796-08 for XM-Comm operation?

The IW1796-08 is designed to operate exclusively with the iW662-05 or iW662-08 secondary-side controllers for full XM-Comm functionality. These variants are explicitly listed in the Ordering Information table for IW1796-08 and support QC2.0/QC3.0 protocols with synchronized voltage/current request transmission. Using any other secondary controller-including other iW662 variants-may result in incomplete XM-Comm handshake or loss of rapid charge features.

What protection features are built into IW1796-08 for cable and connector reliability?

The IW1796-08 includes advanced soft-short protection that detects gradual degradation in cables/connectors by monitoring output voltage undershoot and current anomalies. Unlike traditional latch-off OCP, it reduces average output power progressively during fault conditions-maintaining partial functionality while preventing thermal runaway. This behavior is enabled by internal fault control logic and requires no external components, and is validated for use with the IW1796-08's specific k_CC = 0.422 and 3.0V CC shutdown threshold.