Description

The SC1405B is a Dual-MOSFET Driver with an internal Overlap Protection Circuit to prevent shoot-through. Each driver is capable of driving a 3000pF load in 15ns rise/ fall time and has ULTRA-LOW propagation delay from input transition to the gate of the power FET’s. Adaptive Overlap Protection circuit ensures that the synchronous FET does not turn on until the top FET source has reached a voltage low enough to prevent shoot-through. The delay between the bottom gate going low to the top gate transitioning high is externally programmable via a capacitor to minimize dead time. The bottom FET may be disabled at light loads by keeping S_MOD low to trigger asynchronous operation, thus saving the bottom FET’s gate drive current and inductor ripple current. An internal voltage reference allows threshold adjustment for an Output Over-Voltage protection circuitry, independent of the PWM controller.

Features

◆ Fast rise and fall times (15ns with 3000pf load)
◆ 14ns max. Propagation delay (BG going low)
◆ Adaptive and programmable shoot-through protection
◆ Wide input voltage range (4.5-25V)
◆ Power saving asynchronous mode control
◆ Output overvoltage protection/overtemp shutdown
◆ Under-Voltage lock-out and power ready signal
◆ Less than 10µA stand-by current (EN=low)
◆ Improved drive version of SC1405TS
◆ High frequency (to 1.2MHz) operation allows use of small inductors and low cost capacitors in place of electrolytics

Applications

◆ High Density/Fast transient microprocessor power supplies
◆ Motor Drives/Class-D amps
◆ High efficiency portable computers