UC3843D8TRG4

Power Supply Controllers, Monitors Overview

The UC3843D8TRG4 is a current-mode PWM controller manufactured by Texas Instruments, designed for off-line and DC to DC converter applications. It operates within a supply voltage range of 7.6V to 30V with a typical operating current of 25 mA. The device supports Boost, Buck, Flyback, and Forward topologies, featuring a switching frequency of 500 kHz and a maximum duty cycle of 100%. It provides a single output capable of sourcing 200 mA, with rise and fall times of 50 ns. The component functions reliably across an operating temperature range of 0°C to +70°C and is housed in an 8-SOIC surface-mount package.

Power Supply Controllers, Monitors Feature Summary

• Implements current-mode pulse width modulation control optimized for high-performance power conversion
• Features automatic feed-forward compensation to enhance load response characteristics
• Includes pulse-by-pulse current limiting and double pulse suppression for robust operation
• Integrates under-voltage lockout with hysteresis and an internally trimmed bandgap reference

Power Supply Controllers, Monitors Applications

• Off-line AC to DC converters
• DC to DC step-down (Buck) converters
• Flyback power supplies
• Forward converter designs

Power Supply Controllers, Monitors Procurement Notes

Verify the specific suffix 'G4' indicates lead-free and RoHS compliance status as defined by Texas Instruments documentation. Confirm the SOIC-8 package dimensions and pinout match the target PCB footprint requirements. Ensure the operating temperature range of 0°C to +70°C aligns with the intended environmental conditions. Cross-reference the manufacturer part number against official distributors to confirm current production status and availability.

Power Supply Controllers, Monitors Selection Notes

Select this component when a current-mode PWM controller with integrated protection features is required for isolated or non-isolated power stages. The 500 kHz switching frequency allows for compact magnetic component sizing. Consider the 200 mA output drive capability for direct gate driving of external MOSFETs in low-to-medium power applications. Verify that the input voltage range covers the system's minimum start-up and maximum operating voltages.

Power Supply Controllers, Monitors Part Context

This device belongs to the UCx84x family of current-mode PWM controllers from Texas Instruments. It shares functional similarities with the UC2843 and UC3843 series, offering industry-standard pinouts and performance characteristics. The 'D8' designation specifies the SOIC-8 package variant, while 'TRG4' denotes tape-and-reel packaging with lead-free and RoHS-compliant materials.

Power Supply Controllers, Monitors Replacement Considerations

Direct pin-compatible substitutes include the UC3843D8 and UC3843N variants from Texas Instruments. Other manufacturers offer functionally equivalent parts such as the MC3843 or NCP1606, though electrical parameters and pin configurations must be verified against the original datasheet before implementation.