7.3.2 I²C Interface Timing

Table 7-5. AC Characteristics of I²C InterfaceApplicable over the recommended operating range from T_A = -40°C to +125°C, V_CC = +2.7V to +5.5V.

Parameters	Symbol	Fast-Mode Plus		Units
		Min.	Max.
SCL Clock Frequency	fSCL	—	1000	kHz
SCL High Time	tHIGH	260	—	ns
SCL Low Time	tLOW	500	—	ns
Start Setup Time	tSU.STA	260	—	ns
Start Hold Time	tHD.STA	260	—	ns
Stop Setup Time	tSU.STO	260	—	ns
Data in Setup Time	tSU.DAT	50	—	ns
Data in Hold Time	tHD.DAT	0	—	ns
Input Rise Time(1, 3)	tR	—	120	ns
Input Fall Time(1, 3)	tF	20 x (VDD/5.5V)(5)	120	ns
Clock Low to Data Out Valid	tAA	—	450	ns
Time bus must be free before a new transmission can start (1)	tBUF	500	—	ns
Pulse width of spikes that must be suppressed by the input filter(4)	tSP	—	50	ns

Note:

1. Values are based on characterization and are not tested.
2. AC measurement conditions: input pulse voltages: 0.3 x V_CC to 0.7 x V_CC, input rise and fall times: ≤ 50 ns.
3. System designers must ensure that all AC parametrics are met. Rise fall times shown are for the Fast Mode Plus (1 MHz) of operation. For slower clock speeds, the rise and fall times may be increased but must still meet the industry standard I²C specification UM10204.
4. Input filters on the SDA and SCL pins will suppress noise spikes of less than 50 ns.
5. Backwards compatibility is necessary for the Fast mode (400 kHz) specifications.