The SCM1212B is a driver integrated with MOSFETs for the primary side of a push-pull power. The chip can function at the lowinput voltageof3V,and will not be damaged under the high input voltage of 9V in one second.The device contains ,two drive systems and two power MOSFET,andeach drive system decides circuit’s direction of one primary winding.Each drive system includes one power NMOSFET.Two drive systemsoperateinturns to achieve push-pull drive. Two power NMOSFETs are highly symmetrical in order to decrease the degree of magnetic biasingof push-pulltopology.The SCM1212B is also integrated with three key technologies to improve reliability. The first one is soft start function ,which limitsthecurrentof MOSFET to avoid the damage caused by the large current impact when turning on the power,and quantitatively guarantees the capacitiveloadinCC load mode.The second one is output over-current and short circuit protection.On the one hand, the SCM1212B distinguishes betweentheover-current protection and the short-circuit protection,which can control the short-circuit temperature rise while guarantee the capacitiveload. Ontheother hand, the chip can adjust protection’s threshold based on the input voltage and temperature to improve the consistency. The last oneisovertemperature protection,when the chip operates beyond the specified temperature,it will enters the dormancy state automatically.It will not operateuntilthe temperature decreases to the set point.
Isolated Interface Power Supply for CAN, RS-485, RS-232 etc.
