MM3878

For AC-DC control ICs, MinebeaMitsumi offers primary side control ICs that support PWM + QR combined control, and secondary side synchronous rectification control ICs that can dynamically change the timing off. MM3878 is a secondary side synchronous rectification control IC that supports PWM(Pulse Width Modulation)/ QR (Quasi-Resonant) control, which dynamically changes the off timing according to the power supply status to maximize the effect of synchronous rectification and immediately turns off in the event of an abnormality such as a sudden load change. This prevents backflow. MM3878 is a secondary side synchronous rectification control IC to drive the MOSFET in the Flyback converter. It is able to achieve very high efficiency by replacing secondary rectifier diode with MOSFET and MM3878. It is possible to correspond to various efficiency restrictions. And it is effective for the miniaturization of the power supply by the heat sink reduction and so on. By  providing the power from the drain terminal, you can operate the synchronous rectification on the high side (output terminal side) without the need for additional  auxiliary windings on the secondary side. The turn-on/off status of the synchronous rectifier MOSFET is controlled based on the drain-source voltages of itself. The  turn-off timings are automatically optimized inside the MM3878 to enhance the effectiveness of synchronous rectification. The package is SOT-26E.

MM3878 features :

• Supports DCM Mode and CCM Mode
• Directly input VD signal
• Power supply from Drain (KVD Supply Function)
• Automatic turn off timing
• Automatic minimum on time setting
• Operating voltage of VD pin : 180V (Absolute maximum voltage 200V)
• Operating voltage of VCC pin : 4.75V to 34V (Not use KVD supply function)
• Operating voltage of VCC pin : 3V to 8V (Use KVD supply function)
• IC supply current : Typ. 0.7mA (VCC=15V)
• Supports frequency : ～ 300kHz
• Package SOT-26E

MM3878 applications :

• AC-DC Adaptor
• USB-PD adapter
• Printer
• General purpose power supply