atmega32c1 ATMEL Corporation, atmega32c1 Datasheet - Page 256

• Manufacturer Part Number: atmega32c1
• Description: Atmega32m1 Automotive 8-bit Avr Microcontroller With 32k/64k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

256
ATmega32/64/M1/C1
ATmega32/64/M1/C1 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 communication
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 ATmega32/64/M1/C1 immunizes the address detection against any kind of voltage
variations.
Table 19-1.
Table 19-2.
Note:
Physical
Address
0
1
2
3
4
5
6
7
Physical
Address
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
1. 5V range: Max R
3V range: Max R
Example of Resistor Values(±5%) for a 8-address System (AVcc = 5V
Example of Resistor Values(±1%) for a 16-address System (AVcc = 5V
1 000
2 200
3 300
4 700
6 800
10 000
15 000
22 000
2 000
2 400
2 700
3 300
3 900
4 700
5 600
6 800
8 200
9 100
11 000
13 000
16 000
18 000
20 000
24 000
Resistor Value
Resistor Value
R
R
load
load
(Ohm)
(Ohm)
load
load
30KΩ
15KΩ
Minimum Voltage
Minimum Voltage
Measured (V)
Measured (V)
0.1
0.22
0.33
0.47
0.68
1
1.5
2.2
0.2
0.24
0.27
0.33
0.39
0.47
0.56
0.68
0.82
0.91
1.1
1.3
1.6
1.8
2
2.4
Typical Voltage
Typical Voltage
Measured (V)
Measured (V)
Maximum Voltage
Maximum Voltage
Measured (V)
Measured (V)
7647A–AVR–02/08
(1)
(1)
)
)