n00b Question alert!!!

[Fariniac]

Greets all, been reading these forums for ages, finally got off arse and joined

And now the "idiot" question, I have earched and found all sorts of things to do with TTL but no info on what TTL actually is.

So, what is TTL (including what TTL stands for) and how do I use it?

I have just bought me a 70 - 100mW 635nm LD including driver board from OdicForce.com and it has TTL on the board so wondering what it's for.......

Thanks, Fariniac

 

[Hemlock_Mike]

Transistor - Transistor Logic.  It is basic logic for gates etc.  It means that 0= off and 1= on.  Send a stream of 1's and 0's to that laser and it will flash.

OH Logic 1 = 5 volts

Mike

 

[Fariniac]

ah, cool. Thanks.  Is there a set voltage range for the 0's and 1's or does it vary from diode to diode?

lol, you must have editted that as I was typing this q out...nvm,....cheers mate

 

[lasersbee]

IF your Driver board has a TTL input... then that input is rated for 0-5Vdc input...
as HM has stated...

In TTL language... 0 Volts on your TTL input equals a (0) or OFF Condition..

Likewise... in TTL language... 5 Volts on the TTL input equals a (1) or ON condition..

That 0v or 5V does not go to the Laser Diode directly... it is used to control
the driving circuit that supplies the proper voltages/current for the LD...


Jerry

 

[Hemlock_Mike]

Jerry -- very well stated -- Thank you

With a PWM circuit using a simple 555 driver circuit, you can vary the power.

Mike