Fully integrated switch and sensor monitors system power

Jon Lawson

Texas instruments has introduced two multi-switch detection interface (MSDI) devices that consume up to 98%t less system power than conventional discrete solutions and significantly reduce design complexity.

The TIC12400 and TIC12400-Q1 are the first switch and sensor monitors that directly interface with resistor-coded switches.

The sensors natively monitor the inputs and decoding the resistor path of as many as 54 switches in one device, offloading the signal decoding task from the processor.

By directly monitoring and providing built-in diagnostics for 24 channel inputs, the devices’ polling sequence architecture reduces the system microcontroller active time, significantly cutting system power usage for applications including automotive body electronics and factory and building automation equipment.

The higher efficiency means designers can reduce system power consumption from milliamps to microamps in applications that need high efficiency.

On-device monitoring allows the microcontroller to go into a low-power sleep mode and use less power when idle, which is essential for applications like automotive start/stop or when a car is parked for extended periods of time.

Eliminating up to 120 discrete components, the TIC12400-Q1 has an input-sharing and matrix mode that helps monitor 54 switches and sensors.

The highly integrated device also includes adjustable wetting currents, timing controls, thresholds and built-in redundant circuitry for protection, which increases system-level reliability by reducing potential points of failure.

Integrated electrostatic discharge (ESD) protection and self-diagnostic features reduce external protection components. The new devices meet International Organization for Standardization (ISO) 10605 ±8-kV ESD protection requirements, preventing potential fault events from damaging internal circuitry.

The fully configurable devices independently monitor and protect 24 inputs, providing more headroom for the host microcontroller to perform other functions.

The TIC12400EVM-KIT evaluation module enables designers to quickly and easily evaluate the new device’s capabilities. 

Designers of automotive body control modules can decrease system cost and vehicle weight by using the new device to create a smarter, more centralised architecture, reducing the number and overall weight of wires going into the harness.

The TIC12400-Q1, TIC12400 and TIC10024-Q1 are available in volume through the TI store and authorized distributors.

System designers who don’t require high-volume input monitoring can select the TIC10024-Q1 to simplify the configuration for managing digital-only inputs. All three devices come in a 9.7-mm-by-4.4-mm thin-shrink small outline package (TSSOP).