ON Semiconductor UC3843BDR2 - High Performance Current Mode PWM Controller

The UC3843BDR2 from ON Semiconductor is a high-performance, fixed-frequency current mode PWM controller that is widely used in power supply applications. This integrated circuit is designed to offer a cost-effective solution for off-line and DC-to-DC converter applications by providing the necessary features to control fixed frequency, current mode switched mode power supplies.

With its ability to operate up to a frequency of 500kHz, the UC3843BDR2 is an ideal choice for applications requiring high switching frequencies. The device comes in a compact 8-pin SOIC package, making it suitable for space-constrained applications. It is characterized by a minimal number of external components, which simplifies design and reduces overall system cost.

The UC3843BDR2 features an internally trimmed oscillator for precise frequency control and an internal ramp compensation to ensure stable operation over a wide range of voltages and currents. The device also includes a current sense comparator with a latched off capability to provide cycle-by-cycle current limiting, which is critical for protecting the power supply and the load in the event of an overcurrent condition.

Another key feature of the UC3843BDR2 is its under-voltage lockout with hysteresis, which ensures that the power supply operates only when the input voltage is within an acceptable range. This prevents damage to the power supply and the load during conditions of insufficient input voltage. The device also offers a low startup and operating current, making it suitable for low power applications.

Overall, the UC3843BDR2 is a reliable and efficient solution for designers looking to implement a current mode control strategy in their power supply designs. With its robust feature set and high performance, it continues to be a popular choice for a wide range of power management applications.