T435-800T

Overview

The STMicroelectronics T435-800T is a four-quadrant Snubberless Triac designed for AC power switching applications. It features an RMS on-state current rating of 4 A and a repetitive peak off-state voltage of 800 V. The device supports a surge current of 31 A and operates within a junction temperature range of -40°C to 125°C. Key electrical parameters include a maximum gate trigger current of 35 mA, a maximum gate trigger voltage of 1.3 V, and a holding current of 35 mA. Packaged in a TO-220 through-hole housing with three pins, it eliminates the need for external snubber circuits under defined limits.

Feature Summary

• Snubberless technology enables direct switching without external RC snubber circuits when operating within specified limits.
• High static dV/dt immunity reduces the risk of false triggering during rapid voltage transients.
• Robust dynamic turn-off commutation ensures reliable operation in high di/dt environments.

Applications

• Control of universal motors in power tools
• Switching of electro valves in industrial systems
• Motor control in kitchen aid equipment
• Load management in dishwashers

Procurement Notes

Verify the specific suffix 'T' corresponds to the tube packaging configuration required for assembly. Confirm that the 800V blocking voltage and 4A current ratings align with the system's peak load requirements. Ensure the TO-220 package dimensions fit the designated PCB footprint and thermal management strategy. Cross-reference the datasheet revision date to confirm parameter stability against older component versions.

Selection Notes

Select this component for AC loads requiring high commutation capability without complex gate drive circuitry. The Snubberless feature simplifies design by removing external components typically used for dv/dt protection. Verify that the application's peak transient currents remain below the 31A surge limit. Consider the 125°C maximum junction temperature when calculating thermal dissipation for enclosed enclosures.

Part Context

The T435 series belongs to STMicroelectronics' Snubberless Triac family, optimized for logic-level gate drive and high noise immunity. This series replaces conventional triacs in appliance and industrial controls by integrating internal structures that withstand line transients. The T435-800T specifically targets 800V applications, offering a rugged alternative to standard thyristors in compact modules.

Replacement Considerations

Direct pin-compatible replacements within the same voltage and current class should be verified for identical gate trigger characteristics. Substitutes must support Snubberless operation to maintain the original circuit's simplicity. Ensure any alternative device meets the 800V repetitive peak off-state voltage requirement for equivalent safety margins.