MAX256ASA+T

The MAX256ASA+T is a 3W primary-side transformer H-bridge driver for isolated supplies in 8 pin NSOIC package. The device contains an on-board oscillator, protection circuitry and internal FET drivers to provide up to 3W of power to the primary winding of a transformer. It can be operated using internal programmable oscillator or can be driven by an external clock for improved EMI performance. Regardless of the clock source being used, an internal flip-flop stage guarantees a fixed 50% duty cycle to prevent DC current flow in transformer. It includes under voltage lockout for controlled start up. The device prevents cross-conduction of H-bridge MOSFETs by implementing break before make switching. Thermal shutdown circuitry provides additional protection against damage due to over temperature conditions. It is used in isolated power supplies, isolated communications links and telecommunications.

• Supply voltage range is 3V to 5.5V
• Operating temperature range from -40°C to 125°C
• Simple, flexible design provides Up to 3W to the transformer in isolated power supplies
• Internal resistor-programmable oscillator mode
• External clock mode with watchdog, disable mode
• Integrated system protection, under voltage lockout
• Maximum supply current is 3mA at MODE = VCC
• Maximum switching frequency is 1.35MHz at MODE = VCC, RS = 10.5Kohm
• Maximum watchdog timeout is 55µs at MODE = GND

Applications

Power Management

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party