The UC3846Q from Texas Instruments is a high-performance current mode pulse width modulation (PWM) controller that provides all the necessary features to implement off-line or DC-to-DC fixed-frequency current mode control schemes with a minimal external parts count. This integrated circuit is designed for high-speed operation, including an oscillator frequency range up to 500 kHz and total propagation delays less than 200 ns.
With its robust and reliable design, the UC3846Q is perfect for a wide range of power supply applications, including but not limited to switch-mode power supplies, DC-DC converters, and battery chargers. Its enhanced features include under-voltage lockout (UVLO), leading-edge blanking of the current sense input, and a latch for single pulse metering.
Key Features:
- Trimmed Oscillator for Precise Frequency Control
- Oscillator Frequency Guaranteed at 500 kHz
- Current Mode Operation to 500 kHz
- Automatic Feed Forward Compensation
- Pulse-by-Pulse Current Limiting
- Enhanced Load Response Characteristics
- Under-Voltage Lockout with Hysteresis
- Double Pulse Suppression
- High Current Totem Pole Output
- Internally Trimmed Bandgap Reference
- 500-mA Peak Output Source/Sink Capability
The UC3846Q's current mode control technique provides excellent audio susceptibility and inherent line feed-forward topology. The device also features a trimmed oscillator for precise duty cycle control, under-voltage lockout for automatic shutdown during power-up and power-down, and high current totem-pole output designed to source or sink high peak current. The onboard 5-V regulator is capable of providing IC power during operation.
Overall, the UC3846Q is a versatile, feature-packed PWM controller that offers a reliable and efficient solution for designers looking to enhance the performance of their power supply systems. Its industry-standard package and pinout make it easy to upgrade existing designs or integrate into new applications.
