UC3843 - Current Mode PWM Controller

The UC3843 IC is a current Mode PWM Controller, meaning it can be used to provide a constant current by varying the output voltage to the load. While building Switch mode supplies with feedback there are two modes of control that is commonly used, one is voltage mode control where the output voltage will kept constant irrespective of the current (CV mode) and the other is current mode control where the output current will be constant (C mode) irrespective of the voltage.

The UC3843 can be used to regulate or limit current in application like SMPS, RPS, DC-DC Converters, Line voltage regulators etc.. So if you are looking for an IC to  produce PWM signals for controlling a power switch based on the current flowing through the circuit then this IC might be the right choice for you.

UC3843 Specifications

• Current-Mode PWM controller
• Operating Voltage: 7.0V to 8.2V
• Output pin current: 1A
• Analog input range: -0.3 to 6.3V
• Oscillation Frequency: 52 Typically
• Gain: 3V
• Maximum source current: 22mA
• Low Output Voltage: 0.08V
• High Output Voltage: 13.5V