CY8CKIT-017 Cypress Semiconductor Corp, CY8CKIT-017 Datasheet - Page 20

• Manufacturer Part Number: CY8CKIT-017
• Description: KIT DEV CAN/LIN EXPANSION BOARD
• Manufacturer: Cypress Semiconductor Corp
• Series: -r

Specifications of CY8CKIT-017

• Accessory Type: Expansion Module
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: CY8CKIT-001, CY8CKIT-030, CY3280-22X45
• Other names: 428-3108

Hardware
4.3
4.3.1
4.3.2
20
LIN Physical Layer Transceiver Circuits
The two LIN physical layer transceiver circuits on the Expansion Board use a TJA1020 LIN
transceiver device. This device translates high-voltage LIN bus signals to and from digital CMOS
signals with standard TTL voltage levels.
There are three signals used between each LIN circuit and the PSoC controller. For the LIN1 circuit,
the three signals are LIN1_RX, LIN1_TX, and LIN1_NSLP. For the LIN2 circuit, the three signals are
LIN2_RX, LIN2_TX, and LIN2_NSLP. Any data signals on the LIN bus are sent to the PSoC by the
LINx_RX signal. Any data signals driven by the PSoC on the LINx_TX signal will be driven onto the
LIN bus. The LINx_NSLP signals are used to put the LIN transceiver device in and out of sleep.
By default, there are no pull up resistors on the LINx_TX signals. There is a pull up resistor footprint
provided (R14 on LIN1_TX, R16 on LIN2_TX) on each LINx_TX signal if it is desired to have a pull
up resistor on this signal.
See the datasheet for the TJA1020 device for details on each of the three signals of the LIN
transceiver.
LIN Bus Connectors
The following table shows the pinout of both of the 3-pin LIN connectors (P4 and P5) on the
Expansion Board.
Table 4-2. LIN Connector Pinouts
By default, pin 1 of both LIN connectors (P4 and P5) are left floating. However, if the "LIN1EXTPWR"
jumper (JP4) is populated, pin 1 of the LIN1 connector is connected to the VIN power rail of the DVK
and EBK. Or, if the "LIN2EXTPWR" jumper (JP5) is populated, pin 1 of the LIN2 connector is
connected to the VIN power rail of the DVK and EBK. Populating either one of these jumpers is
useful if it is desirable power up other LIN nodes through the either of the LIN connectors, or if it is
desired to power up the DVK and EBK from the power supply of some other LIN node.
Warning: Take extra precaution when populating the "LIN1EXTPWER" or "LIN2EXTPWR" jumper.
The DVK or EBK can be damaged if the DVK and EBK are powered by a power supply at the VIN
rail and a different power supply is connected through pin 1 of either LIN connector. Also, it is
important to ensure that any other LIN nodes that will be powered from the LIN connectors on the
Expansion Board do not draw too much current.
LIN Circuit Isolation
Both LIN circuits can be completely isolated from the rest of the CY8CKIT-001 development kit by
removing resistors R19, R23, and R25 (to isolate the LIN1 circuit) or R20, R24 and R26 (to isolate
the LIN2 circuit). Each of these resistors is 0. This is useful if either of the LIN circuits are not
needed, but other circuits on the EBK are. In this case, isolating a LIN circuit ensures that the LIN
circuit does not interfere with any other circuits that share the same pins. The footprints for R19,
R23, R25, R20, R24, and R26 are designed so that they can be reconnected easily with a "solder
jumper" instead of repopulating the footprints with a 0 resistor.
Pin
1
2
3
NC (VBAT)
LIN_BUS
GND
LIN1
CY8CKIT-017 CAN/LIN Expansion Board Kit Guide, Doc. # 001-57814 Rev. *B
NC (VBAT)
LIN_BUS
LIN2
GND