The IC provides two complementary high current outputs to drive Power Mosfets. The IC is dedicated to properly drive secondary Synchronous Rectifiers medium power, low output voltage, high efficiency in Forward Converters. From a synchronizing clock input, STSR2P generates two driving signals with the self-setting of dead time between complementary pulses. The IC operation prevents secondary side shoot-through conditions providing proper timing at the outputs turn-off transition. This smart function operates through a fast cycle-after-cycle control logic mechanism based on an internal high frequency oscillator, synchronized by the clock signal. A fixed anticipation in turning-off the OUTGATE1 with respect to the clock signal transition is provided, while the anticipation in turning off the OUTGATE2 can be set through external components. The adopted transitions revelation mechanism makes circuit operation independent by the forward magnetic reset technique used, avoiding most of the common problems inherent in self-driven synchronous rectifiers. A special Inhibit function allows the shut-off of OUTGATE2. This feature makes discontinuous conduction mode possible.
The STSR2P and STSR2PM are smart driver ICs dedicated to driving secondary synchronous rectifiers in medium power, low output voltage, high efficiency forward converters. The STSR2P provides two complementary high current outputs to drive power MOSFETs, while the STSR2PM is optimized for operation at very low duty-cycle values. Both devices utilize a smart turn-off anticipation timing operation independent from the forward magnetic reset technique to prevent secondary side shoot-through conditions.
| Supply Voltage Range | 4.5V to 5.5V |
|---|---|
| Typical Peak Output Current Source | -2A |
| Operating Frequency | 20 to 750 kHz |
| Continuous Power Dissipation | 270 mW |
| Storage Temperature Range | -55 to +150 °C |
| Operating Junction Temperature Range | -40 to +125 °C |
| Duty Cycle Shut Down (STSR2P) | 13% |
The supply voltage range is from 4.5V to 5.5V.
The STSR2P automatically turns off the outputs when the duty-cycle is lower than 13%.
While the STSR2P shuts down below 13% duty cycle, the STSR2PM works even at very low duty-cycle values.