L5991D

The L5991D is a Primary Pulse Width Modulation (PWM) Controller with standby. It is developed in BCD60II technology, has been designed to implement off line or DC-DC power supply applications using a fixed frequency current-mode control. Based on a standard current-mode PWM controller this device includes some features such as programmable soft start, IN/OUT synchronization, disable (to be used for over voltage protection and for power management), precise maximum duty cycle control, 100ns leading edge blanking on current sense, pulse by pulse current limit, overcurrent protection with soft start intervention and standby function for oscillator frequency reduction when the converter is lightly loaded.

• Current-mode control PWM
• Fully latched PWM logic with double pulse suppression
• Programmable duty cycle
• Standby function
• Programmable soft-start
• Primary overcurrent fault detection with re-start delay
• PWM UVLO with hysteresis
• IN/OUT Synchronization
• Latched disable
• Internal 100ns leading edge blanking of current sense