Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

Interface 3 volt OCXO to 5 volt logic.

Status
Not open for further replies.
schmitt trigger

schmitt trigger

Advanced Member level 5
Joined
Apr 17, 2013
Messages
2,725
Helped
859
Reputation
1,722
Reaction score
850
Trophy points
1,393
Activity points
18,445
I have a 3 volt powered 10 Mhz OXCO, which has to be interfaced and divided down in frequency with 5 volt logic.

My solution, which is working on a sample of one, is to use a 74HCT393 as my interface, based on the following datasheet info:

OCXO output levels: Voh min = 2.7; Vol max = 0.3 with a drive of +/- 4 mA.
HCT393 input levels: Vih min = 2.0, typ = 1.6; Vil max = 0.8, typ = 1.2

Which means I'm fully spec protected.

But in addition to complying with the logic levels, are there any other caveats which I should consider?
 

Some of these oscillators can be optionally powered from either 3v or 5v.
Better safe than sorry, but double check that 5v supply is not an option.
 

Thanks Tony, but this particular device has a max operating Vdd = 3.46v
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top