xmega a3u - Elfa

XMEGA A3U
36.16 Two-Wire Interface Characteristics
Table 36-32 describes the requirements for devices connected to the Two-Wire Interface Bus.
The Atmel AVR XMEGA Two-Wire Interface meets or exceeds these requirements under the
noted conditions. Timing symbols refer to Figure 36-7.
Figure 36-7.
Two-wire interface bus timing.
t of
t HIGH
t LOW
t r
SCL
t SU;STA
t HD;STA
t HD;DAT
t SU;DAT
t SU;STO
SDA
t BUF
Table 36-32.
Two-wire interface characteristics.
Symbol Parameter Condition Min. Typ. Max. Units
V IH Input High Voltage 0.7V CC V CC +0.5
V IL Input Low Voltage 0.5 0.3×V CC
V hys Hysteresis of Schmitt Trigger Inputs 0.05V CC
(1)
V OL Output Low Voltage 3mA, sink current 0 0.4
t r Rise Time for both SDA and SCL 20+0.1C b
(1)(2)
300
t of Output Fall Time from V IHmin to V ILmax 10pF < C b < 400pF (2) 20+0.1C b
(1)(2)
250
t SP Spikes Suppressed by Input Filter 0 50
I I Input Current for each I/O Pin 0.1V CC < V I < 0.9V CC -10 10 µA
C I Capacitance for each I/O Pin 10 pF
f SCL SCL Clock Frequency f PER
(3)
>max(10f SCL , 250kHz) 0 400 kHz
R P
Value of Pull-up resistor
f SCL ≤ 100kHz
f SCL > 100kHz
V CC
– 0.4V
----------------------------
3mA
100ns
---------------
C b
300ns
---------------
C b
V
ns
Ω
8386B–AVR–12/11
90