3.4.1 CAN/LIN Enablement
The EVB provides an array of 0-ohm resistors that are populated according to the variant of the S12VM device that is
populated on the board. The following image shows the different resistor pairs. Only one resistor on each pair must be
populated at a time.
Figure 6. Resistor selection for CAN/LIN options
Table 18. Populating Resistors for CAN/LIN Enablement
S12ZVML12MKH
S12ZVMC12MKH
MCU Pin
LIN
LIN + CAN(*)
CAN(*)
1 – LIN / BCTLC
R41
R41
R32
64 – LGND / VDDC
R33
R33
R42
4 – PS1 (LPTXD / TXCAN)
R43
R34
R34
3 – PS0 (LPRXD / RXCAN)
R44
R35
R35
Other settings
J3 (VDDC supplied from USB,
J25)
Open
Close
Open
J2 (supply to VDDC regulator) Open
Open
Close
(*) Using external CAN transceiver
3.4.2 LIN Physical Layer
The LIN bus pin provides a physical layer for single-wire communication in automotive applications. The LIN physical layer
is designed to meet the LIN Physical Layer 2.2 specification from LIN consortium.
The LIN physical interface pins (LPTXD and LPRXD) are available on a 2-pin header, J17. This can be used to interface
another MCU to the LIN physical interface integrated into the S12ZVML device.
The LIN bus includes an integrated pull-up device, which can be a strong pull-up (~34 Kiloohm) or a high impedance value
(~300 Kiloohm), selectable by software. A 220 pF capacitor is added at the LIN bus pin, according to the device
recommendation. ESD protection is provided in the form of two back-to-back diodes in a single package, D8.
By default, the EVB is configured to operate in slave mode. It can be converted into a Master node by populating a 1
Kiloohm resistor at R45. The footprint in the PCB will hold a 0603 size surface mount resistor. This resistor is connected in
series with the diode required from the battery voltage node. In this case, the battery voltage is taken from the HD node, the
supply to the FET bridge high side drains.
Design Considerations
S12ZVM12EVB Evaluation Board User Guide, Rev. 2, 03/2016
Freescale Semiconductor, Inc.
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