Infineon ICE3BR1765JZ: An Integrated CoolMOS™ PFC and Quasi-Resonant PWM Combo Controller

In the relentless pursuit of higher efficiency, reduced component count, and superior performance in power supply design, the integration of critical functions onto a single chip has become a pivotal strategy. The Infineon ICE3BR1765JZ stands at the forefront of this innovation, representing a highly advanced combo controller that seamlessly merges a Power Factor Correction (PFC) controller with a Quasi-Resonant (QR) PWM controller. This integration is specifically engineered to streamline the development of compact, high-efficiency SMPS (Switch-Mode Power Supplies) for applications such as adapters, PC main power, and LCD TVs.

The core of this device's functionality lies in its two-stage control architecture. The first stage features an innovative critical conduction mode (CrM) PFC controller. This stage is responsible for shaping the input current to follow the input voltage sinusoidally, ensuring a high power factor (typically >0.95) and minimizing harmonic distortion to meet stringent international standards like EN61000-3-2. By employing a built-in totem-pole gate driver for the external PFC MOSFET, it simplifies the external circuitry. Its variable switching frequency operation helps to optimize efficiency across the entire load range.

The second stage is a quasi-resonant current-mode PWM controller for the main DC-DC conversion. QR operation, also known as valley switching, allows the integrated high-voltage startup cell to power the controller directly from the drain pin, drastically reducing standby power consumption. This architecture significantly enhances overall efficiency, particularly at light loads, by minimizing switching losses.

Key advantages of the ICE3BR1765JZ include:

High Level of Integration: Combining both controllers into an 8-pin DIP or 7-pin SMD package drastically reduces the external component count, board space, and overall system cost.

Superior Efficiency: The combination of CrM PFC and Quasi-Resonant PWM switching ensures exceptionally high efficiency across a wide load range, aiding in compliance with global energy efficiency regulations (e.g., CoC V5, DoE Level VI).

Enhanced Reliability: The IC incorporates a comprehensive suite of protection features, including over-voltage protection (OVP), over-load protection (OLP), over-current protection (OCP), and brown-out detection, safeguarding both the power supply and the end-equipment.

Reduced EMI: The quasi-resonant operation at valley switch-on reduces switching noise and electromagnetic interference, simplifying EMI filter design.

ICGOODFIND: The Infineon ICE3BR1765JZ is a powerhouse of integration, masterfully combining a high-performance CoolMOS™-compatible PFC stage with a quasi-resonant PWM controller. It is an optimal solution for designers aiming to achieve compact form factors, high efficiency, and robust reliability in modern switch-mode power supplies, all while simplifying the design process and accelerating time-to-market.

Keywords: Power Factor Correction (PFC), Quasi-Resonant PWM, Combo Controller, High Efficiency, System Integration