Voting resources, early voting, and poll worker information - VOTE. ... Adafruit is open and shipping.
0

Adafruit Pro Trinket 3.3V Question
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Adafruit Pro Trinket 3.3V Question

by jordani on Wed Jul 19, 2017 3:40 pm

I purchased an Adafruit Pro Trinket 3.3V board a while back and noticed in Eagle that the SMD crystal doesn't have two capacitors attached to it. I built a custom board for a project I am working on and based the schematic off the Adafruit Pro Trinket 3.3V. I can only program the atmega328 on this board when I remove the SMD crystal and connect the XTAL1 & XTAL2 pads to an external crystal that is connected to two capacitors.

Why is this the case? Can I purchase a SMD crystal that has the capacitors built into it? I'd prefer to use this board and not have to redesign it again.

Note: The crystal on my board is 12MHz, while the external crystal I am using is 16MHz. Could this be the reason why I am having issues?
jordani
 
Posts: 1
Joined: Mon Mar 03, 2014 10:59 am

Re: Adafruit Pro Trinket 3.3V Question

by franklin97355 on Thu Jul 20, 2017 2:04 am

The one on the Pro Trinket is probably an oscillator with internal caps.

franklin97355
 
Posts: 21586
Joined: Mon Apr 21, 2008 2:33 pm
Location: Lacomb, OR.

Please be positive and constructive with your questions and comments.