11 高性能电流控制型_UC3842.pdfVIP

Page No. : 1/12 AX3842P / AX3842S High Performance Current Mode Pwm Controlers 8-Lead Plastic DIP-8 Description Package Code: P The AX3842 Series is high performance fixed frequency current mode controllers. That is specifically designed for Off-Line and DC To DC converter applications ? offering the designer a costeffective solution with minimal external components. These integrated circuits feature a trimmed oscillator for precise duty cycle control. A temperature compensated reference, high gain error amplifier, current sensing 8-Lead Plastic SO-8 compara-tor, and a high current totem pole output ideally suited for driving a Package Code: S power MOSFET. Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering. Features ? Trimmed Oscillator for Precise Frequency Control ? Oscillator Frequency Guaranteed at 250 kHz ? Current Mode Operation to 500 kHz ? Automatic Feed Forward Compensation ? Latching PWM for Cycle-By-Cycle Current Limiting ? Internally Trimmed Reference with Undervoltage Lockout ? High Current Totem Pole Output ? Undervoltage Lockout with Hysteresis ? Low Startup and Operating Current Absolute Maximum Ratings Symbol Parameter Value Unit Vi Supply Voltage (low impedance source) 30 V Vi Supply Voltage (Ii30mA) Self Limiting IO Output Current