3.3.1 AC Parameters: Single-Wire Interface

Figure 3-3. AC Timing Diagram: Single-Wire Interface
Table 3-3. AC Parameters: Single-Wire InterfaceUnless otherwise specified, applicable from TA = -40°C to +100°C, VCC  = +2.0V to +5.5V, CL = 100 pF.
Parameter Symbol Direction Min. Typ. Max. Unit Conditions
Start Pulse Duration tSTART To Crypto Device 4.10 4.34 4.56 µs
From Crypto Device 4.60 6 8.60 µs
Zero Transmission High Pulse tZHI To Crypto Device 4.10 4.34 4.56 µs
From Crypto Device 4.60 6 8.60 µs
Zero Transmission Low Pulse tZLO To Crypto Device 4.10 4.34 4.56 µs
From Crypto Device 4.60 6 8.60 µs
Bit Time(1) tBIT To Crypto Device 37 39 µs If the bit time exceeds tTIMEOUT-SWI, ATECC608C may enter Sleep mode.
From Crypto Device 41 54 78 µs
Turn Around Delay tTURNAROUND From Crypto Device 64 96 131 µs ATECC608C will initiate the first low going transition after this time interval following the initial falling edge of the start pulse of the last bit of the transmit flag.
To Crypto Device 93 µs After ATECC608C transmits the last bit of a group, the system must wait this interval before sending the first bit of a flag. It is measured from the falling edge of the start pulse of the last bit transmitted by ATECC608C.
IO Timeout tTIMEOUT-SWI To Crypto Device 45 65 85 ms ATECC608C may transition to the Sleep mode if the bus is inactive longer than this duration.
Note:
  1. tSTART, tZLO, tZHI and tBIT are designed to be compatible with a standard UART running at 230.4 kBaud for both transmit and receive. The UART must be set to seven data bits, no parity and one Stop bit.