SLOS887E September 2014 – December 2018 TMP112-Q1
In order for the two-wire bus to operate at frequencies above 400 kHz, the master device must issue an Hs-mode master code (0000 1xxx) as the first byte after a START condition to switch the bus to high-speed operation. The TMP112-Q1 device does not acknowledge this byte, but switches the input filters on the SDA and SCL pins and the output filters on the SDA pin to operate in Hs-mode thus allowing transfers at up to 2.85 MHz. After the Hs-mode master code has been issued, the master transmits a two-wire slave address to initiate a data-transfer operation. The bus continues to operate in Hs-mode until a STOP condition occurs on the bus. Upon receiving the STOP condition, the TMP112-Q1 device switches the input and output filters back to fast-mode operation.