Dear Sirs,
My customer asked us about difference of PIn5 between TCAN1042-Q1 and Sn65HVDA1040A-Q1.
TCAN1042-Q1 is "VIO" and SN65HVDA1040A-Q1 is "SPLIT" description.
My customer needs the SPLIT function but it is not listed on the data sheet of TCAN1042-Q1.
Can the TCAN1042-Q1 operate as SPLIT function?
Please let me know the difference between these two terminals and SPLIT operation on TACN1042-Q 1
Best Regards,
Y.Hasebe
Hasebe-san,
The VIO and SPLIT pins have different functions.
The VIO pin on the TCAN1042-Q1 is an input pin which allows the user to set the logic levels of the device to 3.3V or 5V. For example, if the user applies 3.3V to the VIO pin, the TXD and RXD pin voltage levels will change from the standard 0-5V of CAN, to 0-3.3V, in order to work with 3.3V microprocessors.
The SPLIT pin on the SN65HVDA1040A-Q1 is an output pin which drives the common-mode voltage (0.5*VCC) and is meant to connect between CANH and CANL through 60Ω resistors. See an example below:
By implementing this topology, you're driving the common-mode voltage to 0.5*VCC with another source besides the internal circuitry. This can help when there are more CAN nodes on the bus drawing current, and driving the common-mode voltage below 0.5*VCC, and can also help with electromagnetic emissions by stabilizing the common-mode and eliminating deviations from noise on CANH and CANL, and having the filter capacitor helps with this as well.
With newer devices, these features are less effective because the leakage current has been optimized (high impedance when not being used on the bus) so that the common-mode voltage doesn't drop to level of older devices when more nodes are placed on the bus.
Regards,
