UC3844BVDR2G

The UC3844BVDR2G is a high-performance integrated DC–DC switching controller optimized for off-line and DC–DC converter applications. It is especially well-suited for switch mode power supplies using the forward, fly-back, buck, or boost topologies. It offers peak current-mode control with a user-adjustable oscillator, precise count-down current limiting and thermal overload protection along with many other features.

UC3844BVDR2G is widely used in commercial and industrial applications such as telecom power supplies, distributed power systems, laptop power supplies, switches, and ac/dc converters for both line-powered and battery-powered applications.

The working principle of UC3844BVDR2G can be broken down into two parts: 1. High-side current sense and peak-current mode control2. Low-side current sense and fixed-frequency current-mode controlThe high-side current-sense amplifier monitors and controls the inductor current in switch-mode power supplies. It provides peak current-mode control using an internal current-limit comparator. The on-time and cycle-by-cycle current limiting can be set by the user.The current-sense amplifier has an adjustable gain range, allowing precise current limiting even at high load currents. The output current can be monitored and trimmed at an external resistor. An on-chip temperature-compensation circuit allows the user to compensate for temperature variations in the sensed current level, ensuring stable operation across temperature extremes.The low-side current-sense amplifier monitors and controls the output current in switch-mode power supplies. It provides fixed-frequency current-mode control using an internal oscillator. The frequency can be set by the user, allowing a wide range of operating frequencies from 10 kHz to 50 kHz, enabling the system designer to achieve a wide range of design goals. The output current can be monitored and trimmed at an external resistor.UC3844BVDR2G also provides a wide range of protective features such as adjustable leading edge and trailing edge blanking, over-voltage protection, under-voltage protection, thermal shutdown and current limiting for protection against overloads and short circuits.In summary, the UC3844BVDR2G is a high-performance integrated DC–DC switching controller designed for off-line and DC–DC converter applications. It provides peak current-mode control with a user-adjustable oscillator, precise count-down current limiting, thermal overload protection and a wide range of other features. Its wide range of operating frequencies, adjustable gain range and adjustable temperature compensation circuit make it an ideal choice for a variety of applications.