Using the ATAVRAUTO200
ATAVRAUTO200 User Guide
2-5
7698A–AUTO–01/07
Table 2-1.
LIN ressources
Figure 2-3.
LIN transceiver and power supply
Note:
The LIN transceiver undervoltage protection can be disabled by removing the
NISP jumper.
Note:
The NISP jumper has to be removed when programming.
2.4.2
Power supply measurement
The voltage measurement is realized with a bridge of resistors. The read value is 0.281
of the LIN power supply (47 K
Ω
/ (47 K
Ω
+ 120 K
Ω
)). Input voltage on channel 1 of the
ADC is limited to 5.1V by a zener diode. This will give a voltage reading range from 0 to
18.1V with Vcc as reference.
The power supply measurement can be performed using the A/D converter. See the
ATmega48/88/168 datasheet for how to use the ADC. The input voltage value (V
IN
) is
calculated with the following expression:
Where:
V
IN
= Input voltage value (V)
V
ADC7
= Voltage value on ADC-1 input (V)
Function
Port
State
Description
LIN_NSLP
PD2
Low
LIN transceiver in Sleep mode
High
LIN transceiver in normal mode
NRES_LIN
PC6
Low
Perform MCU reset when NISP Jumper is inserted
High
No Action
+
V
B
a
t
G
N
D
L
IN
V
IN
3.55
V
A DC
1
×
=
