ATSHA204 ATMEL [ATMEL Corporation], ATSHA204 Datasheet - Page 31

• Manufacturer Part Number: ATSHA204
• Description: Atmel CryptoAuthentication
• Manufacturer: ATMEL [ATMEL Corporation]

When the device is active (not in sleep or idle mode), the input voltage thresholds are different, depending on the state of
TTLenable (bit three) within the I2C_Address byte stored in the configuration zone of the EEPROM. When a common voltage
is used for the ATSHA204 V
thresholds to track the supply as follows:
Figure 7-5. V
If the voltage supplied to the V
connected, then the system designer may chose to set TTLenable to zero, which enables a fixed input threshold according to
the following table.
Table 7-6.
Parameter
Input Low Voltage
Input High Voltage
3.20
3.00
2.80
2.60
2.40
2.20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
2.0
V
IH
IL
and V
and V
IH
IL
(Device Active, TTLenable = 1) – All I/O Interfaces
(Device Active, TTLenable = 0) – All I/O Interfaces
Symbol
3.0
CC
V
V
CC
IH
IL
pin and the input pull-up resistor, then this bit should be set to a one, which permits the input
pin of the ATSHA204 is different from the system voltage to which the input pull-up resistor is
VIH, VIL when TTLenable is 1
GND-
Min
0.5
1.5
Vcc
4.0
Typ
V
Max
0.5
0.5
CC
+
5.0
Unit
V
V
Notes
When device is active and TTLenable bit in
configuration memory is zero; otherwise, see
above.
When device is active and TTLenable bit in
configuration memory is zero; otherwise, see
above.
6.0
Atmel ATSHA204 [DATASHEET]
VIH
VIL
8740D−CRYPTO−3/12
31