Teensy to MLX90621ESF Design Review request

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riodda

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Hi all, i've did my first electronic design (plase bear in mind i'm a mechanincal engineer), the teensy shield I designed contains one canbus trascriver one volteage regulator for power supply and one IR sensor MLX90621ESF.
The purpose of this cirquit is to measure the tyre temperature accoss the tire with and stream measurements to the canubs.
Before ordering the boards i would love is somebody can have a look to the board routing to see if i did some mistakes ! My main concern is about the pullups for the I2C.
The MLX sensor it's calibrated and works a 2.6V while the micro is at 3.3V, i've attached the pulups to 3.3v but i'm not sure thats the right way nor if it's harmfoul for the sensor if the high state of the communication lines is higer than the power supply.
Thanks ! View attachment Teensy_Can_Mk1.zip
 
- VCC pad from the SN65HVD230D is not connected
- Connection from 3.3V to GND
can1.PNG
It's generally a good idea to run the DRC (Design Rule Check) and ERC in Eagle.

I couldn't find a datasheet for the MLX90621ESF. It's probably not ok to pull the sda/scl line higher than 2.6V.

Are the CAN Bus connector and the Teensy board on the same side of the pcb? Can you access the usb port with the CAN connector in front?

I've modified the design a bit:
- All 4 common pins from the UA78L02A to GND
- SN65HVD230D Vcc to 3.3V and additional decoupling capacitor
- I2C pull ups to 2.6V (Teensy VIH min is 2.31V @ 3.3V)
- move the input and output capacitors closer to the 3.3V regulator
- rotate MLX90621ESF
- move all parts to the bottom side
- disconnect the 2nd 3.3V pin from the Teensy (All 3.3V pins are connected together internally)

View attachment Teensy_Can_Mk1_R.zip
 
Last edited:
- VCC pad from the SN65HVD230D is not connected
- Connection from 3.3V to GND
View attachment 4899
It's generally a good idea to run the DRC (Design Rule Check) and ERC in Eagle.

I couldn't find a datasheet for the MLX90621ESF. It's probably not ok to pull the sda/scl line higher than 2.6V.

Are the CAN Bus connector and the Teensy board on the same side of the pcb? Can you access the usb port with the CAN connector in front?

I've modified the design a bit:
- All 4 common pins from the UA78L02A to GND
- SN65HVD230D Vcc to 3.3V and additional decoupling capacitor
- I2C pull ups to 2.6V (Teensy VIH min is 2.31V @ 3.3V)
- move the input and output capacitors closer to the 3.3V regulator
- rotate MLX90621ESF
- move all parts to the bottom side
- disconnect the 2nd 3.3V pin from the Teensy (All 3.3V pins are connected together internally)

View attachment 4898

Many thanks for you help, i've updated the gerbers and i'll wait oshpark to deliver !
Thanks.
 
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