UC2845D8

Power Supply Controllers, Monitors Overview

The UC2845D8 is a current-mode PWM controller from the UCx84x series, designed for high-performance DC/DC converters. It operates with a switching frequency up to 500 kHz and supports Boost, Flyback, and Forward topologies. The device features a single output capable of sourcing 1 A drive current. It functions within a supply voltage range of 7.6 V to 30 V. The maximum duty cycle is limited to 50%. Operating temperatures span from -40°C to +85°C. The component is housed in an 8-SOIC surface-mount package.

Power Supply Controllers, Monitors Feature Summary

• Implements current-mode control architecture for improved transient response and inherent line feed-forward compensation.
• Provides a dedicated high-current output stage capable of driving power MOSFETs directly without external buffer amplifiers.
• Integrates precision oscillator and comparator circuitry to maintain stable switching frequencies across varying input conditions.

Power Supply Controllers, Monitors Applications

• Boost converter designs requiring efficient step-up voltage regulation
• Flyback power supplies for isolated AC-DC conversion applications
• Forward converter implementations for medium-power isolated DC-DC systems

Power Supply Controllers, Monitors Procurement Notes

Verify that the specific ordering suffix matches the required tape-and-reel packaging configuration. Confirm that the device variant aligns with the intended thermal management requirements for the target operating environment. Ensure compatibility with existing PCB footprint dimensions before finalizing procurement decisions.

Power Supply Controllers, Monitors Selection Notes

Select this component when designing non-isolated or isolated converters requiring current-mode control characteristics. Consider the 50% maximum duty cycle limitation when determining transformer turns ratios or inductor values. Evaluate the 1 A output drive capability against the gate charge requirements of the selected power switch devices.

Power Supply Controllers, Monitors Part Context

This part belongs to the UCx84x family of current-mode PWM controllers, which are widely utilized in industrial and consumer power supply designs. The UC2845 variant specifically targets applications where a fixed maximum duty cycle is acceptable. It serves as a cost-effective solution for standard switching regulator architectures.

Power Supply Controllers, Monitors Replacement Considerations

UC2845AD8TR

Power Supply Controllers, Monitors FAQ

What is the maximum duty cycle specification for the UC2845D8?

The maximum duty cycle is limited to 50% due to internal comparator thresholds.

Which switching topologies are supported by this controller?

The UC2845D8 supports Boost, Flyback, and Forward converter topologies.