SR036 Datasheet | Supertex Inc

Features ❑ Accepts peak input voltages up to 700V ❑ Operates directly off of rectified 120V AC or 240V AC ❑ Integrated linear regulator ❑ Minimal power dissipation ❑ No high voltage capacitors required ❑ No transformers or inductors required General Description The Supertex SR036 and SR037 are inductorless, dual output off-line controllers. They do not require any transformers, inductors, or high voltage input capacitors. The input voltage, HVIN, is designed to operate from an unfiltered full wave rectified 120V or 240V AC line. It is designed to control an external N-channel MOSFET. When HVIN is between VGS(th) to 40V, where VGS(th) is the threshold voltage of the external MOSFET, the external N-channel MOSFET is turned on allowing it to charge an external capacitor connected to VSOURCE. An unregulated DC voltage will develop on VSOURCE. Once HVIN is above 45V, the N-channel MOSFET is turned off. The maximum gate voltage for the external MOSFET is 24V. The unregulated voltage is approximately 18V. The SR036 also provides a regulated 3.3V whereas the SR037 provides a regulated 5.0V. WARNING!!! Galvanic isolation is not provided. Dangerous voltages are present when connected to the AC line. It is the responsibility of the designer to assure adequate safeguards are in place to protect the end user from electrical shock. Applications ❑ 3.3V or 5.0V power supplies ❑ SMPS house keeping power supplies ❑ White goods ❑ Appliances ❑ Small off-line low voltage power supplies ❑ Lighting controls SR03x Typical Application Circuit ~18V Unregulated 100µF Surge Protection Gate 120VAC or 240VAC SR036 or SR037 VSOURCE VOUT SR036: VOUT=3.3V Regulated SR037: VOUT=5.0V Regulated 1.0µF 06/13/02 Supertex Inc. does not remend the use of its products in life support applications and will not knowingly sell its products for use in such applications unless it receives an adequate "products liability indemnification insurance agreement." Supertex does not assume responsibility for...