UC3845 Current Mode PWM Controller (Pack of 100)

Description:
The UC3845 is a high-performance fixed-frequency current-mode Pulse Width Modulation (PWM) controller IC designed primarily for off-line and DC-to-DC power converter applications. It integrates essential control circuitry that allows designers to build efficient switching power supplies with minimal external components. Its current-mode architecture improves line regulation, simplifies loop compensation, and offers robust protection features for reliable and stable power conversion.

Key Features:

• Fixed-frequency current-mode PWM control for stable and precise switching regulation.

• Current-mode operation up to ~500 kHz, enabling smaller passive components and higher power density.

• Low start-up and operating current (<1 mA) to improve efficiency and reduce auxiliary power requirements.

• Cycle-by-cycle current limiting (latching PWM) for enhanced protection against overload conditions.

• Undervoltage lockout (UVLO) with hysteresis for safe power-up and stable startup behavior.

• High-current totem-pole output capable of directly driving external MOSFET gates.

• Internally trimmed reference and oscillator for precise duty-cycle and frequency control.

Typical Applications:

• AC-DC SMPS (offline power supplies)

• DC-DC Boost, Buck, and Flyback converters

• LED drivers and battery chargers

• Industrial and automotive power electronics systems

• Motor controllers and battery management circuits

Technical Highlights:

• Precision timing and feedback circuitry reduce external component count and design complexity.

• Built-in current sensing and protection features improve system reliability.

• High output drive capability supports efficient switching devices.

Package & Pin Info:
Available in standard 8-pin DIP or SOIC packages for through-hole or surface-mount designs, with dedicated pins for COMP, FB, ISENSE, RT/CT, OUTPUT, VCC, GND, and VREF