UC2843ADW

DC DC Switching Controllers Overview

The UC2843ADW is a current-mode PWM controller from Texas Instruments designed for offline and DC-DC switching power supplies. It operates within a supply voltage range of 10V to 36V, with a typical startup threshold of 16V and shutdown at 10V. The device features an internal 5V reference with ±1% accuracy and supports switching frequencies up to 500 kHz via external components. It provides a single output capable of sourcing or sinking 200 mA, suitable for driving power MOSFETs. The operational temperature range spans from -40°C to +85°C. Packaged in SOIC-8 (DW), it supports Boost, Flyback, and Forward topologies.

DC DC Switching Controllers Feature Summary

• Current-mode control architecture with automatic feed-forward compensation for superior transient response
• Integrated high-precision 5V bandgap reference source with ±1% tolerance
• Asymmetric undervoltage lockout circuitry preventing erratic start-stop behavior during power transitions
• Built-in soft-start mechanism and latchable PWM logic for cycle-by-cycle current limiting

DC DC Switching Controllers Applications

• Flyback converters for off-line power adapters
• Forward converter designs for isolated DC-DC regulation
• Boost topology applications requiring peak current mode control
• General-purpose switching power supply systems

DC DC Switching Controllers Procurement Notes

Verify the specific suffix against official Texas Instruments documentation to confirm package type and temperature grade. Ensure the ordering part number matches the required RoHS compliance status and manufacturing origin. Cross-reference the datasheet revision date to validate parameter accuracy before finalizing procurement specifications.

DC DC Switching Controllers Selection Notes

Select this component when asymmetric UVLO thresholds are critical for reliable startup in flyback circuits. The current-mode operation offers better input voltage rejection compared to voltage-mode alternatives. Consider the 200 mA output drive capability for direct MOSFET gating without additional buffer stages.

DC DC Switching Controllers Part Context

This device belongs to the UCx84x family of current-mode PWM controllers, sharing functional similarities with the UC384x series but optimized for industrial temperature ranges. It serves as a core control IC for isolated and non-isolated power conversion architectures requiring precise duty cycle regulation.

DC DC Switching Controllers Replacement Considerations

UC2843ADWR

DC DC Switching Controllers FAQ

What is the difference between the startup and shutdown voltages?

The UC2843ADW features asymmetric UVLO with a typical startup voltage of 16V and a shutdown voltage of 10V, providing a 6V hysteresis to prevent oscillation during power cycles.

How is the switching frequency determined?

The operating frequency is set by connecting an external resistor and capacitor to the oscillator pins, allowing adjustment up to a maximum of 500 kHz.