AN2334 Datasheet, PDF (18/22 Pages) STMicroelectronics – Complete car door module

Hardware implementation
5
Hardware implementation
AN2334
The voltage regulator, which provides the required 5V during normal mode, is enabled by
the LIN transceiver through Inhibit Output pin INH. To reset the microcontroller with the
watchdog timer in case of a missing pulse, a jumper must be installed in the Voltage
Regulator Reset connector (#1 - Figure 8).
The jumper must be removed in case of microcontroller reprogramming; in fact, in this
phase, the microcontroller cannot provide pulses to the voltage regulator that should provide
a low level reset. Moreover, during the programming phase, to enable the Voltage regulator
a jumper must be installed in the Voltage Regulator Enable connector (#2 - Figure 8)
because in this case the LIN bus interface L9638 cannot provide the enabling voltage.
In summary, the microcontroller can be reprogrammed using the ICP connector (#10 -
Figure 8) by removing the Reset jumper (#1 - Figure 8) and settling the Enable jumper (#2 -
Figure 8). See the ST72F561 datasheet for more details.
A jumper on CB4 connector (#8 - Figure 8) allows using the board without using the LIN
Interface as detailed in Section 3: Local Interconnect Network (LIN) messages.
The board connector locations are given in Figure 8.
Figure 8. Board connectors
3 L9950 Outputs
1 Reset
2 Enable
4 Down Key
5 Up Key
6 - CB5 / 7 – CB3 / 8 - CB4
9 - Window Up Switch
10 ICP Conn
11 Window
Motor
12 Power
Supply
13 L9950
Outputs
1
3
5
7
9
11
13
15
2
4
6
8
10
12
14
16
16 LIN Conn.
15 Wake Up
14 Parallel
Port
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