High power density, fast response fee-controlled switching power supply control chip
SCM1725A chip is a high-performance current mode PWM control chip, the chip internal integrated drain minimum withstand voltage of 650V 2A power tube, high-voltage start pin by directly connecting to the power supply bus voltage, to achieve rapid charging of the VDD bypass capacitor, at the same time, in the chip to start the short-circuit protection, the VDD capacitor voltage drops to the point where the VDD under-voltage, high-voltage fast start circuit At the same time, after the chip starts the short circuit protection, the VDD capacitor voltage drops to the VDD undervoltage point, the high voltage fast start circuit restarts to charge the VDD bypass capacitor until it reaches the VDD start voltage, the start circuit stops working to reduce the loss.
Due to the chip built-in light load frequency hopping mode, so that it has a very good efficiency performance at light loads, but also built-in duty cycle slope compensation, internal loop compensation and other circuits, so that the system loop operation is more stable. In order to improve system reliability, the chip also integrates a series of internal protection functions. In addition, the chip integrates an EN pin, external logic high level, can control the chip into a very low power consumption mode, and at the same time make the VDD pin voltage is controlled at about 8.6V voltage. When the chip has enough heat dissipation conditions, in the open 75 ℃ environment 3S on/off intermittent operation, the maximum output peak power up to 20W.
