CFE18 - Can Bus Switch Board
CFE18 stands for "Can Bus Function Extension," or colloquially, "Can Switch Board" - why do you need this module?
Can Bus connections in your vehicle can sometimes pose significant challenges. Especially in motorsport applications, when electronics need to be housed in the steering wheel, and information from turn knobs or push buttons needs to be transmitted via Can Bus.
CANchecked now offers a small additional module that provides 17 inputs: 8 for switches (low side) and 9 for analog inputs (0-5V signal). A voltage converter for connection to a 12V automotive electrical system is also already integrated.
On the board, there are also 3 low side switching outputs with a maximum rating of 0.5A.
The CFE18 Hardware
Measuring just 29x27mm, the board is very compact and can fit anywhere. The pin spacing is 2.54mm - for power supply reasons, it's 3.81mm.
We have added a hole for mounting that can be used as a screw attachment.
CFE18 - Can Bus Termination
A solder jumper is present on the board.
If you close this jumper, the Can Bus termination with 120 ohms is activated. By default, the solder jumper is OPEN.
Motorsport Steering Wheel
An application could be a motorsport steering wheel. In the image, you can see the approximate size, with the steering wheel hub being 50mm in diameter. With just 4 connections via a spiral cable, various inputs can be transmitted via Can Bus.
Connection Options
With the CFE18, you can connect switches as well as Trimpots (adjustment knobs).
But sensors such as oil pressure, fuel pressure, boost pressure, exhaust backpressure, and integration into a custom enclosure are also possible.
Digital Outputs
The CFE18 has three digital outputs. These can carry a maximum of 500mA and switch to ground (LOW SIDE).
For this purpose, you send a Can Bus Frame every 100ms (CAN Id is configurable here - a timeout is activated after a 500ms pause between frames, and the outputs are deactivated):
(0=inactive, 1=active)
AIN Smoothing
If the analog inputs fluctuate too much, they can be smoothed using software. This is individually configurable for each analog input.
With every transmission, the analog inputs are evaluated (default 20Hz).
For example, if a smoothing factor of 4 is set, the average of the last 16 measurements is taken. This makes the value smoother but also responds more slowly to fluctuations. Finding a good balance is essential.
The configuration is done via Can Bus.