CY8CKIT-017 Cypress Semiconductor Corp, CY8CKIT-017 Datasheet - Page 19

• 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

4.2.3
4.2.4
4.2.5
CY8CKIT-017 CAN/LIN Expansion Board Kit Guide, Doc. # 001-57814 Rev. *B
This is useful if it is desirable power up other CAN nodes through the CAN connector, or if it is
desired to power up the DVK and EBK from the power supply of some other CAN node.
Warning: Take extra precaution when populating the "CANEXTPWR" jumper. The DVK or EBK can
be damaged if the DVK and EBK have their own power supply powering the VIN rail and a different
power supply is connected through pin 9 of the CAN connector. Also, it is important to ensure that
any other CAN nodes that will be powered from the CAN connector on the Expansion Board do not
draw too much current.
CAN Bus Termination
The CAN specification requires that CAN nodes that are located physically at the end of the CAN
bus must terminate the CAN differential signals with 120. The EBK features a 120 termination
resistor (R6) that can be enabled or disabled by using jumper JP2. If JP2 is populated, the
termination resistor is active. If JP2 is not populated, the termination resistor is not active.
The termination resistor is active (JP2 is populated) by default.
Figure 4-2. JP2 Jumper
Choke Footprint
A footprint for a common-mode signal suppression choke is available on the Expansion Board, but it
is not populated. This footprint can be populated with a B82789C0 (or equivalent) choke to suppress
common-mode signals on the CAN bus. If a choke component is mounted on the L1 footprint,
resistors R4 and R12 must be removed from the board. The choke component has no effect if these
two resistors are not removed.
Figure 4-3. CAN Choke Footprint
CAN Circuit Isolation
The CAN circuit can be completely isolated from the rest of the CY8CKIT-001 development kit by
removing resistors R3, R5, and R10. Each of these resistors is 0. This is useful if the CAN circuit is
not needed, but other circuits on the EBK are. In this case, isolating the CAN circuit ensures that the
CAN circuit does not interfere with any other circuits that share the same pins. The footprints for R3,
R5, and R10 are designed so that they can be reconnected easily with a "solder jumper" instead of
repopulating the footprints with a 0 resistor.
Hardware
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