TI drives isolation technology forward with latest solid-state relays

Texas Instruments (TI) has introduced a new portfolio of solid-state relays, including automotive-qualified isolated drivers and switches, that deliver improved levels of reliability to help make electric vehicles (EVs) safer.

The TPSI3050-Q1 isolated switch driver with an integrated 10-V gate supply and the TPSI2140-Q1 1,400-V, 50-mA isolated switch both integrate power and signal isolation across a single barrier using an approach that improves reliability, while reducing the solution size and cost compared to existing electromechanical relays and solid-state photo-relays.

The devices are the first in a new solid-state relays portfolio that will also include ICs designed for high-voltage industrial applications.

With high-voltage systems becoming more prevalent, especially with the increased adoption of EVs, the integration of more functionality within TI’s isolation technology, will mean that engineers will be able to reduce the size, cost and complexity of high-voltage power supplies while maintaining the safety of next-generation automotive and industrial systems.

These solid-state relays can disconnect and connect loads through a single isolation barrier in microseconds – compared to milliseconds for electromechanical relays – to enable safer operation of high-voltage automotive systems.

The TPSI3050-Q1, which offers reinforced isolation up to 5 kVRMS, also provides an operating lifetime that’s 10 times higher than electromechanical relays, which can degrade over time. Additionally, the TPSI2140-Q1 offers basic isolation up to 3.75 kVRMS, enabling it to achieve more than four times higher time-dependent dielectric breakdown reliability than solid-state photo-relays.

The solid-state relays integrate power and signal transfer in a single chip while also eliminating at least three components from their designs, significantly reducing solution size while cutting BOM costs by as much as 50%.

The TPSI3050-Q1 reduces solution size up to 90% compared to mechanical relay solutions by integrating the functions of an isolated power supply, digital isolator and gate driver. The TPSI2140-Q1 reduces solution size by as much as 50% compared to traditional solid-state photo-relay solutions by integrating a signal field-effect transistor and resistors, and eliminating the need for a reed relay.

Designed for high-voltage measurements and insulation monitoring, the TPSI2140-Q1 works with a battery-pack monitor such as the BQ79631-Q1 to detect insulation faults in 800-V battery-management systems faster and with higher accuracy than solid-state photo-relays.

The TPSI2140-Q1 enables the use of <1-MΩ resistors and withstands over 300% more avalanche current than traditional photo-relays to help enable safer human-system interaction.