Automotive 35-V multi-switch detection interface (MSDI) with SPI & integrated ADC

The TIC12400-Q1 is an advanced

Multiple Switch Detection Interface (MSDI) designed to detect external switch status

in a 12-V automotive system. The TIC12400-Q1 features an integrated 10-bit ADC to

monitor multi-position analog switches and a comparator to monitor digital switches

independently of the MCU. Detection thresholds can be programmed for the ADC and the

comparator to support various switch topologies and system non-idealities. The

device monitors 24 direct switch inputs, with 10 inputs configurable to monitor

switches connected to either ground or battery. 6 unique wetting current settings

can be programmed for each input to support different application scenarios. The

device supports wake-up operation on all switch inputs to eliminate the need to keep

the MCU active continuously, thus reducing power consumption of the system. The

TIC12400-Q1 also offers integrated fault detection, ESD protection, and diagnostic

functions for improved system robustness. The TIC12400-Q1 supports 2 modes of

operations: continuous and polling mode. In continuous mode, wetting current is

supplied continuously. In polling mode, wetting current is turned on periodically to

sample the input status based on a programmable timer, thus the system power

consumption is significantly reduced.