TOP261EN Off-line Switcher IC

Power Integrations’ TOPSwitch-HX series employs the same tried-and-true TOPSwitch architecture. The TOP261EN switcher IC is a single CMOS chip that has a high voltage 700V power MOSFET, PWM control, fault protection, and other control circuitry. This IC has a number of novel capabilities that help to lower system costs while also improving design flexibility, performance, and energy efficiency.

Depending on the package type, 1 or 3 more pins are added to the conventional TOPSwitch DRAIN, SOURCE, and CONTROL terminals. As a result, some capabilities are enabled, such as line detection (OV/UV, line feed-forward/DCMAX reduction), accurate externally set current limit, and remote ON/OFF. It also has frequency selection (132 kHz/66 kHz) and synchronisation to a lower frequency externally.

Soft-start, 132 kHz switching frequency (automatically lowered at light load), and frequency jittering are included in all package variants for reduced EMI. There are also larger creepage packages, a wider DCMAX, and hysteretic thermal shutdown. Furthermore, all essential parameters (current limit, frequency, and PWM gain) have tighter temperature and absolute tolerances, making design easier and lowering system costs.

These IC functions as  a switched-mode power supply chip that converts a current at control input to a duty cycle at the open-drain output of high voltage power MOSFET. During normal functioning of  IC, the duty cycle of  power MOSFET reduces linearly with increase in CONTROL pin current.

​APPLICATIONS:

• A 35 W, dual output- Universal input power supply with high efficiency
• 150 W, 250-380 VDC Input Power Supply with high efficiency
• 20 W Continuous – 80 W Peak, Universal Input Power Supply with high efficiency
• 65 W- Universal Input Power Supply with high efficiency