36.15 TWI

Figure 36-6. TWI - Timing Requirements
Table 36-21. TWI - Timing Specifications
Symbol Description Min. Typ.✝ Max. Unit Condition
fSCL SCL clock frequency 1000 kHz Max. frequency requires system clock over 12 MHz
VHYS Hysteresis of Schmitt Trigger inputs 0.05 × VDD 0.4 × VDD V
VOL Output low voltage 0.4V V Iload = 3 mA, VDD > 2V
0.2 × VDD Iload = 2 mA, VDD ≤ 2V
IOL Low-level output current 3 mA VOL = 0.4V, VDD > 2
2 0.2 × VDD, VDD ≤ 2V
tSP * Spikes suppressed by the input filter 0 50 ns
tHD_STA * Hold time (repeated) Start condition 4.0 µs fSCL ≤ 100 kHz
0.6 fSCL ≤ 400 kHz
0.26 fSCL ≤ 1 MHz
TLOW * Low period of SCL Clock 4.7 µs fSCL ≤ 100 kHz
0.6 fSCL ≤ 400 kHz
0.35 fSCL ≤ 1 MHz
THIGH * High period of SCL Clock 4.0 µs fSCL ≤ 100 kHz
0.6 fSCL ≤ 400 kHz
0.26 fSCL ≤ 1 MHz
tSU_STA * Setup time for a repeated Start condition 4.7 µs fSCL ≤ 100 kHz
0.6 fSCL ≤ 400 kHz
0.26 fSCL ≤ 1 MHz
tHD_DAT * Data hold time 0 ns SDAHOLD[1:0] = 0x0
300 900 SDAHOLD[1:0] = 0x3
tSU_DAT * Data setup time 250 ns fSCL ≤ 100 kHz
100 fSCL ≤ 400 kHz
50 fSCL ≤ 1 MHz
tSU_STO * Setup time for Stop condition 4 µs fSCL ≤ 100 kHz
0.6 fSCL ≤ 400 kHz
0.26 fSCL ≤ 1 MHz
tBUF * Bus free time between a Stop and Start condition 4.7 µs fSCL ≤ 100 kHz
1.3 fSCL ≤ 400 kHz
tCS Client Clock Stretching delay 250 ns

Unless otherwise specified, data in the “Typ.” column is at TA = 25°C and VDD = 3.0V . These parameters are not tested and are for design guidance only.

* These parameters are not tested and are for design guidance only.