The TOPSwitch-FX family has excellent design flexibility and low system cost, and features a fully integrated soft start to eliminate or reduce the cost of external components. The series also features an externally adjustable accurate current limit, wider duty cycle, smaller input capacitor, line undervoltage detection, line overvoltage shutdown, line feed forward, maximum duty cycle reduction, frequency jittering, zero load regulation, 132kHz frequency, half frequency option, hysteretic thermal shutdown, large thermal hysteresis to prevent PC board overheating and standard packaging.
The TOPSwitch-FX family is an integrated off-line switcher designed for flexible and eco-smart power supply applications. It combines a high-voltage power MOSFET, PWM control, and fault protection onto a single CMOS chip with added terminals for programmable line overvoltage/undervoltage shutdown, current limiting, and remote on/off capabilities.
The family includes the TOP232, TOP233, and TOP234 models, available in DIP-8B, SMD-8B, and TO-220-7B packages. Key features include a 132 kHz switching frequency, frequency jittering to reduce EMI, and cycle skipping for reduced no-load consumption. The devices regulate to zero load without dummy loading and offer hysteretic thermal shutdown.
| Switching Frequency | 132 kHz |
|---|---|
| Operating Temperature | 50 °C ambient |
| Package Types | DIP-8B, SMD-8B, TO-220-7B |
The TOP234Y provides a maximum practical continuous power of 75 W in an open frame design with adequate heat sinking.
Connecting the FREQUENCY pin to the CONTROL pin sets the switching frequency to 66 kHz.
The device uses cycle skipping to reduce no-load consumption.