Infineon Technologies ICE5QR0680AG | Demoboard AN_201702_PL83_007

Description

This AN is an engineering report for a 42 W 12 V and 5 V demo board designed in a QR flyback converter topology using the 5th generation QR CoolSET™ ICE5QR0680AG. The target applications of ICE5QR0680AG are either auxiliary power supplies for white goods, PCs, servers or TVs, or enclosed adapters for Blu-ray players, set-top boxes, games consoles, etc. With the CoolMOS™ integrated into this IC, it greatly simplifies the design and layout of the PCB. The new improved digital frequency reduction with proprietary QR operation offers lower EMI and higher efficiency for a wide AC range by reducing the switching frequency difference between low- and high-line. The enhanced Active Burst Mode (ABM) power enables flexibility in standby power operation range selection, and QR operation during ABM. As a result, the system efficiency over the entire load range is significantly improved compared to a conventional free-running QR converter implemented with only maximum switching frequency limitation at light loads. In addition, numerous adjustable protection functions have been implemented in ICE5QR0680AG to protect the system and customize the IC for the chosen application. In case of failure modes such as brownout or line over-voltage, V CC over-/under-voltage, open control-loop or over-load, output over-voltage, over-temperature, V CC short-to-ground and Current Sense (CS) short-to-ground, the device enters protection mode. By means of the cycle-by-cycle Peak Current Limitation (PCL), the dimensions of the transformer and the current rating of the secondary diode can both be optimized. Thus, a cost-effective solution can easily be achieved.

Features

• Novel quasi-resonant switching scheme
• Rapid and adjustable start-up with cascode configuration
• 2 level selectable active burst mode level
• Built-in digital soft-start
• Cycle by cycle peak current limitation
• Digital frequency reduction with decreasing load for higher efficiency
• Adjustable line input over-voltage and brown IN/OUT protection
• VCC and CS pin short to ground protection
• OLP, output short, output over-voltage, OTP with hysteresis and VCC over/under voltage protection
• Auto-restart for all protection features

Typical applications

• Offline aux SMPS for server, PC power, aircon, refrigerator and audio / Offline main SMPS for adapter, set-top-box, water purifier, TV, industrial SMPS and POE

More information

• Datasheet
• IC product information