UC3845BD1013TR

UC3845BD1013TR is a high performance current mode PWM controller. This control IC provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include a trimmed oscillator for precise DUTY CYCLE CONTROL under voltage lockout featuring start-up current less than 0.5mA, a precision reference trimmed for accuracy at the error amp input, logic to ensure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the offstate. This device has UVLO thresholds of 10V (off), ideally suited off-line applications.

• Trimmed oscillator for precise frequency control, undervoltage lockout with hysteresis
• Oscillator frequency guaranteed at 250KHz, current mode operation to 500KHz
• Automatic feed forward compensation, high current totem pole output
• Latching pwm for cycle-by-cycle current limiting, low start-up and operating current
• Internally trimmed reference with undervoltage lockout
• Output noise voltage is 50µV typical at (10Hz ≤ f ≤ 10KHz Tj = 25°C)
• 52KHz typical frequency, 2.50V input voltage
• Input bias current is -0.1µA typical at (VFB = 5V)
• Unity gain bandwidth is 1Mhz typical at (TJ = 25°C)
• Junction operating temperature range from -40°C to 150°C, SO8 package