Current Mode Controller The UC2845B is a high-performance current-mode PWM controller manufactured by STMicroelectronics.
### **Specifications:**
- **Topology:** Current-mode PWM controller
- **Input Voltage (VCC):** 8.4V to 30V (operating range)
- **Under-Voltage Lockout (UVLO):** 7.9V (turn-on), 7.6V (turn-off)
- **Output Drive Current:** ±1A (peak)
- **Switching Frequency:** Up to 500kHz
- **Duty Cycle Range:** 0% to 100%
- **Reference Voltage:** 5V (±1% accuracy)
- **Operating Temperature Range:** -40°C to +85°C
- **Package Options:** SO-8, PDIP-8
### **Descriptions:**
The UC2845B is designed for offline and DC-DC converter applications. It features a trimmed oscillator for precise duty cycle control, current sensing, and high-gain error amplifier. It includes built-in protections such as under-voltage lockout (UVLO) and cycle-by-cycle current limiting.
### **Features:**
- **Current-Mode Operation:** Improved loop response and simplified feedback compensation.
- **Automatic Feed-Forward Compensation:** Ensures consistent performance over input voltage variations.
- **Pulse-by-Pulse Current Limiting:** Enhances system reliability.
- **Internal Soft-Start:** Reduces inrush current.
- **Low Start-Up Current (<1mA):** Enables efficient power-up.
- **High-Current Totem Pole Output:** Directly drives power MOSFETs.
- **Synchronizable Oscillator:** Allows synchronization with external clock signals.
This device is commonly used in power supplies, battery chargers, and industrial control systems.
