![](http://datasheet.mmic.net.cn/30000/MR80C32-20-D_datasheet_2377239/MR80C32-20-D_297.png)
297
8154B–AVR–07/09
ATmega16A
2. VBOT may be below nominal minimum operating voltage for some devices. For devices where
this is the case, the device is tested down to V
CC = VBOT during the production test. This guar-
antees that a Brown-out Reset will occur before V
CC drops to a voltage where correct
operation of the microcontroller is no longer guaranteed. The test is performed using
BODLEVEL = 1 and BODLEVEL = 0 for ATmega16A.
27.6
External Interrupts Characteristics
27.7
Two-wire Serial Interface Characteristics
Table 27-4 describes the requirements for devices connected to the Two-wire Serial Bus. The ATmega16A Two-wire Serial
Interface meets or exceeds these requirements under the noted conditions.
Table 27-3.
Asynchronous External Interrupt Characteristics
Symbol
Parameter
Condition
Min
Typ
Max
Units
tINT
Minimum pulse width for asynchronous
external interrupt
50
ns
Table 27-4.
Two-wire Serial Bus Requirements
Symbol
Parameter
Condition
Min
Max
Units
VIL
Input Low-voltage
-0.5
0.3 VCC
V
IH
Input High-voltage
0.7 V
CC
V
CC + 0.5
V
Hysteresis of Schmitt Trigger Inputs
0.05 VCC
–V
V
Output Low-voltage
3 mA sink current
0
0.4
V
t
r
Rise Time for both SDA and SCL
20 + 0.1C
b
300
ns
tof
Output Fall Time from VIHmin to VILmax
20 + 0.1Cb
250
ns
t
Spikes Suppressed by Input Filter
0
ns
I
i
Input Current each I/O Pin
0.1V
CC < Vi < 0.9VCC
-10
10
A
Ci
Capacitance for each I/O Pin
–
10
pF
f
SCL
SCL Clock Frequency
f
CK
0
400
kHz
Rp
Value of Pull-up resistor
f
SCL ≤ 100 kHz
f
SCL > 100 kHz
t
HD;STA
Hold Time (repeated) START Condition
f
SCL ≤ 100 kHz
4.0
–
s
fSCL > 100 kHz
0.6
–
s
tLOW
Low Period of the SCL Clock
f
4.7
–
s
f
SCL > 100 kHz
1.3
–
s
tHIGH
High period of the SCL clock
fSCL ≤ 100 kHz
4.0
–
s
f
SCL > 100 kHz
0.6
–
s
t
SU;STA
Set-up time for a repeated START condition
fSCL ≤ 100 kHz
4.7
–
s
fSCL > 100 kHz
0.6
–
s
VCC 0,4V
–
3mA
----------------------------
1000ns
Cb
-------------------
Ω
VCC 0,4V
–
3mA
----------------------------
300ns
Cb
----------------
Ω