3,3V to 5V for controlling stepper motor

E

eryvh

New member
Hi everyone,

I'm working on a project where I need to control a stepper motor driver using a Teensy 4.1. According to the driver datasheet (attached below), it requires a minimum of 5V input signals. However, the I/O pins on the Teensy 4.1 outputs only 3.3V.

After some research, I found that the 74LVC1T45 IC can be used to shift the signal levels from 3.3V to 5V. My question is:
  • Would using the 74LVC1T45 for this purpose be safe for the Teensy 4.1?
Thanks!

1732037356894.png
 

Attachments

  • ACSDME03.pdf
    625 KB · Views: 17
Glanced at the 74LVC1T45 datasheet. Looks like it ought to work.

Many people have successfully used 74AHCT125 and 74HCT245 to boost Teensy's 3.3V signals up to 5V for a wide variety of applications, so I'd recommend giving those a look. If you have step and direction signals for more than 1 motor, these 4 or 8 channel chips might work out better than using several single channel chips. 74AHCT125 and 74HCT245 are also simpler, requiring only the 5V supply for their output.
 
PaulStoffregen said:
Glanced at the 74LVC1T45 datasheet. Looks like it ought to work.

Many people have successfully used 74AHCT125 and 74HCT245 to boost Teensy's 3.3V signals up to 5V for a wide variety of applications, so I'd recommend giving those a look. If you have step and direction signals for more than 1 motor, these 4 or 8 channel chips might work out better than using several single channel chips. 74AHCT125 and 74HCT245 are also simpler, requiring only the 5V supply for their output.
Click to expand...
Thank you! I'll take a look at 74AHCT125, because I need more channels. Just to be sure - can I provide 5v from Teeny pin to these boosters?
 
eryvh said:
Just to be sure - can I provide 5v from Teeny pin to these boosters?
Click to expand...
Yes. The current draw for those parts is low enough that taking it from the Teensy 5V pin (which is basically the 5V from the USB) shouldn't be an issue. Just don't try powering a motor off the Teensy power pins.
Ideally you should also put a small capacitor to ground (~100nF) as close as possible to the buffers Vcc pin.
 
The input structure have a pull-up resistor. Connecting a simple NPN transistor (with resistor on the base) would do the job.
 
Angelo said:
The input structure have a pull-up resistor. Connecting a simple NPN transistor (with resistor on the base) would do the job.
Click to expand...
Or an N channel MOSFET, no resistor needed. That would invert the signal but that should be simple to cope with in code.
But this is assuming the driver pullup is enabled, the diagram indicates that it's optional or switchable to a pull down.
 
You must log in or register to reply here.
Back
Top