SBOS776C March 2016 – March 2021 INA3221-Q1
PRODUCTION DATA
When the bus is idle, the SDA and SCL lines are pulled high by the pull-up resistors. The master generates a start condition followed by a valid serial byte with the 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 INA3221-Q1 does not acknowledge the Hs master code, but does recognize it and switches its internal filters to support 2.44-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 2.44 MHz are allowed. Instead of using a stop condition, the master uses a repeated start conditions to secure the bus in Hs mode. A stop condition ends the Hs mode, and switches all internal INA3221-Q1 filters to support F/S mode.
Figure 8-13 shows the bus timing, and Table 8-2 lists the bus timing definitions.
PARAMETER | FAST MODE | HIGH-SPEED MODE | UNIT | |||
---|---|---|---|---|---|---|
MIN | MAX | MIN | MAX | |||
f(SCL) | SCL operating frequency | 0.001 | 0.4 | 0.001 | 2.44 | MHz |
t(BUF) | Bus free time between stop and start conditions | 1300 | 160 | ns | ||
t(HDSTA) | Hold time after repeated START condition. After this period, the first clock is generated. | 600 | 160 | ns | ||
t(SUSTA) | Repeated start condition setup time | 600 | 160 | ns | ||
t(SUSTO) | STOP condition setup time | 600 | 160 | ns | ||
t(HDDAT) | Data hold time | 0 | 0 | ns | ||
t(VDDAT) | Data valid time | 1200 | 260 | ns | ||
t(SUDAT) | Data setup time | 100 | 10 | ns | ||
t(LOW) | SCL clock low period | 1300 | 270 | ns | ||
t(HIGH) | SCL clock high period | 600 | 60 | ns | ||
tfDA | Data fall time | 500 | 150 | ns | ||
tfCL | Clock fall time | 300 | 40 | ns | ||
tr | Clock rise time | 300 | 40 | ns | ||
Clock rise time for SCLK ≤ 100 kHz | 1000 | ns |