Rainbow Electronics ATmega64M1 User Manual
Page 254
254
8209A–AVR–08/09
ATmega16M1/32M1/64M1
ATmega16M1/32M1/64M1 proposes to have an external resistor used in conjunction with the
Current Source. The device measures the voltage to the boundaries of the resistance via the
Analog to Digital converter. The resulting voltage defines the physical address that the commu-
nication handler will use when the node will participate in LIN communication.
In automotive applications, distributed voltages are very disturbed. The internal Current Source
solution of ATmega16M1/32M1/64M1 immunizes the address detection against any kind of volt-
age variations.
Note:
1. 5V range: Max R
load
30K
Ω
3V range: Max R
load
15K
Ω
Table 23-1.
Example of Resistor Values(±5%) for a 8-address System (AVcc = 5V
)
Physical
Address
Resistor Value
R
load
(Ohm)
Minimum Voltage
Measured (V)
Typical Voltage
Measured (V)
Maximum Voltage
Measured (V)
0
1 000
0.1
1
2 200
0.22
2
3 300
0.33
3
4 700
0.47
4
6 800
0.68
5
10 000
1
6
15 000
1.5
7
22 000
2.2
Table 23-2.
Example of Resistor Values(±1%) for a 16-address System (AVcc = 5V
Physical
Address
Resistor Value
R
load
(Ohm)
Minimum Voltage
Measured (V)
Typical Voltage
Measured (V)
Maximum Voltage
Measured (V)
0
2 000
0.2
1
2 400
0.24
2
2 700
0.27
3
3 300
0.33
4
3 900
0.39
5
4 700
0.47
6
5 600
0.56
7
6 800
0.68
8
8 200
0.82
9
9 100
0.91
10
11 000
1.1
11
13 000
1.3
12
16 000
1.6
13
18 000
1.8
14
20 000
2
15
24 000
2.4