SBOS644D February 2013 – July 2022 INA231
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
When the bus is idle, both the SDA and SCL lines are pulled high by the pull-up devices. The master generates a start condition followed by a valid serial byte containing High-Speed (HS) master code 00001XXX. This transmission is made in fast (400 kHz) or standard (100 kHz) (F/S) mode at no more than 400 kHz. The INA231 does not acknowledge the HS master code, but does recognize it and switches its internal filters to support 2.5-MHz operation.
The master then generates a repeated start condition (a repeated start condition has the same timing as the start condition). After this repeated start condition, the protocol is the same as F/S mode except that transmission speeds up to 2.5 MHz are allowed. Instead of using a stop condition, use repeated start conditions to secure the bus in HS-mode. A stop condition ends the HS-mode and switches all the internal filters of the INA231 to support the F/S mode. A bus timing diagram is shown in Figure 7-1.