The E-UC3843BN is a high-performance, fixed-frequency current-mode PWM controller manufactured by STMicroelectronics, a leader in semiconductor solutions. This integrated circuit is designed to facilitate the construction of low-cost, efficient power supplies with a minimal number of external components, making it ideal for a wide range of applications including switch-mode power supplies (SMPS), DC-DC converters, battery chargers, and power adapters.

Key Features

• Optimized for Off-line and DC-DC Converters: The E-UC3843BN is tailored for various power supply topologies, especially those requiring a fixed-frequency operation.
• Low Startup Current: With a startup current of just 0.5mA (typical), this device ensures minimal power consumption during the initial phase, enhancing the overall efficiency of the system.
• Automatic Feed Forward Compensation: This feature helps to maintain stable operation despite variations in input voltage, ensuring consistent performance.
• Pulse-by-Pulse Current Limiting: Enhanced protection is provided by limiting the current in each pulse, safeguarding the controller and external components from over-current conditions.
• Under-Voltage Lockout (UVLO) with Hysteresis: This function ensures that the device operates only when the supply voltage is within an acceptable range, preventing malfunctions due to low voltage conditions.
• High Current Totem Pole Output: The output stage is capable of driving a power MOSFET or IGBT directly, which simplifies the design of the power stage.
• Trimmed Oscillator Discharge Current: The oscillator's discharge current is accurately trimmed to ensure precise duty cycle control.

Applications

The versatility of the E-UC3843BN makes it suitable for a variety of power management applications. It is commonly used in:

• AC/DC power supplies for personal computers, TVs, and monitors
• Isolated and non-isolated flyback converters
• Forward converters
• Buck and boost DC-DC converters
• Power supplies for battery-operated devices

With its robust feature set and STMicroelectronics' commitment to quality, the E-UC3843BN stands as a reliable choice for designers who require a high-performance PWM controller for their power supply designs.