Renesas IW1790-12B

Overview

The iW1790-12B from Renesas Electronics is a primary-side AC/DC PWM controller optimized for rapid charge adapters supporting Huawei FCP, Qualcomm QC 2.0/3.0, and multi-level CV/CC regulation without secondary feedback. It operates in quasi-resonant mode, delivers <20mW no-load power at 230VAC/5V–2A, and integrates XM-Comm transformer-based communication with iW663-02/iW662-05 secondary controllers.

For engineers reviewing the iW1790-12B datasheet, iW1790-12B pinout, iW1790-12B application, or iW1790-12B equivalent, key selection criteria include its SOIC-8 package, 0.422 kCC startup coefficient, 3.0V/6.5V CC shutdown voltage thresholds (VBUS-dependent), support for 5.25V/9V VBUS configurations, and elimination of optocoupler and loop compensation components.

Technical Context

The iW1790-12B implements primary-side regulation using VSENSE-based auxiliary winding sensing and ISENSE-based cycle-by-cycle current limiting, enabling tight multi-level constant-voltage and constant-current control across 3.6V–12V/1A–3A output ranges. Its XM-Comm interface exchanges real-time voltage requests, current limits, and overvoltage/undershoot data directly via the main transformer with paired iW663-02 or iW662-05 controllers.

It employs source-charging VCC technology to eliminate external active start-up circuits and achieves ultra-low no-load consumption (<20mW) while maintaining dual over-temperature protection (internal OTP + external NTC via SD pin) and SmartDefender+™ fault mitigation for soft shorts without latching.

Key Specifications

Pinout & Package

Package: 8-lead SOIC-8 (standard JEDEC MS-012), surface-mount, RoHS-compliant.

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 INN3265C, the iW1790-12B uniquely combines XM-Comm–based optocoupler-free communication, protocol-specific kCC configuration (0.422), and VBUS-dependent CC shutdown-enabling lower BOM cost and finer-grained rapid charge control in sub-20 W adapters.

Availability

iW1790-12B is available at Aetrix Electronics and suitable for smartphone rapid charging adapters, tablet fast-charge power supplies, and universal travel adapters requiring stable component supply, protocol flexibility (FCP/QC2.0/QC3.0), and ultra-low no-load power.

Supply support for iW1790-12B 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 solutions for automotive, industrial, infrastructure, and IoT applications.

The iW1790-12B belongs to Renesas' Dialog-branded rapid charge controller product line, designed specifically for compact, high-efficiency AC/DC adapters supporting multi-protocol fast charging with minimal external components.

FAQ

What protocols does the iW1790-12B support natively?

The iW1790-12B natively supports Huawei Fast Charger Protocol (FCP), Qualcomm Quick Charge 2.0 and 3.0, and is designed to operate with iW663-02 and iW662-05 secondary controllers for seamless protocol negotiation. It supports 5.25 V and 9 V VBUS configurations and uses XM-Comm to exchange voltage requests and current limits without external signaling components. The iW1790-12B itself does not implement protocol stack logic but enables it through tightly coupled communication with its designated secondary partners.

Does the iW1790-12B require an external optocoupler?

No, the iW1790-12B eliminates the need for an external optocoupler by using Dialog's proprietary XM-Comm transformer-based communication with compatible secondary-side controllers like iW663-02. This bidirectional link transmits output voltage requests, current limits, and protection signals across the isolation barrier using the main power transformer, reducing component count and improving reliability. The iW1790-12B achieves full primary-side regulation and rapid charge responsiveness without optocoupler or secondary feedback circuitry.

What is the significance of the "B" suffix in iW1790-12B?

The "B" suffix in iW1790-12B indicates it is the recommended version for new designs, as confirmed in the official ordering information table. It shares identical electrical specifications and pinout with iW1790-12 but reflects updated manufacturing, qualification, or minor process enhancements. Both variants use the same SOIC-8 package, support FCP/QC2.0/QC3.0, and feature 0.422 kCC and VBUS-dependent CC shutdown. Designers should specify iW1790-12B for new projects to ensure long-term supply and latest revision compliance.

How does the iW1790-12B achieve <20 mW no-load power consumption?

The iW1790-12B achieves <20 mW no-load power consumption through source-charging VCC technology, which eliminates the external active start-up (ASU) circuit. During startup, the IC draws charge directly from the SOURCE pin to energize VCC, then enters ultra-low quiescent current mode during no-load conditions. This architecture, combined with multi-mode PWM/PFM control and optimized gate drive, ensures compliance with stringent energy efficiency standards such as DOE VI and EU CoC Tier 2 - all without compromising dynamic response or regulation accuracy in the iW1790-12B.

Can the iW1790-12B be used without a secondary-side controller?

No, the iW1790-12B is designed exclusively for use with Dialog's iW663-02 or iW662-05 secondary-side controllers. Its XM-Comm functionality, multi-level CV/CC regulation, and protocol-specific voltage transitions depend entirely on bidirectional communication with those designated partners. Using the iW1790-12B without iW663-02 or iW662-05 results in loss of rapid charge capability, unstable regulation, and failure to meet specified performance targets - the iW1790-12B does not operate as a standalone primary-side controller in rapid charge applications.