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,

ATECC608B may enter Sleep mode.

From Crypto

Device

41

54

78

µs

—

Turn Around Delay

tTURNAROUND From Crypto

Device

64

96

131

µs

ATECC608B 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 ATECC608B 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 ATECC608B.

IO Timeout

tTIMEOUT

To Crypto Device

45

65

85

ms ATECC608B 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.

ATECC608B

Electrical Characteristics

© 2020 Microchip Technology Inc.

Summary Datasheet

DS40002239A-page 8