SR087

The Supertex SR087 is an inductorless switching regulator designed to operate directly from a rectifi ed AC line. The operating principle is to turn on a pass transistor when the rectifi ed AC is below the output voltage, and to turn it off when the output voltage reaches a specifi c level. A linear regulator supplied by V_OUT provides an additional fi xed 3.3V output (SR086) or 5V output (SR087). Effi ciencies of around 55% may be realized for loads up to 1W in 120VAC applications, with around 50% effi ciencies for loads up to 800mW in 230VAC applications.

A logic-level enable input allows the SR087 to be disabled useful when the SR08x is employed as a keep-alive  ower supply.

WARNING! Galvanic isolation is not provided. Dangerous voltages are present when connected to the AC line. SR087 is the responsibility of the designer employing the SR08x to ensure adequate safeguards are in place to protect the end user from electrical shock.