Hi http://www-s.ti.com/sc/psheets/schs045a/schs045a.pdf
On page 3-139 (bottom of the page) you will find the possible solutions and on page 3-140 the function truth table of the same. You will require 2 IC's, both programmed as NAND gates. The first 8 bits are connected to the first CD4048B. The EXP input of the first CD4048B must be low. The other 8 bits are connected to the second CD4048B. When you connect the output of the first CD4048B to the EXP input of the second CD4048B you will get a 16 input NAND. girish > I am attempting to connect a pair of CD4048 8-input > expandable gates together to form a 16-input nand gate. I did > not do a very thorough job of writing down some of the notes > which, as I recall weren't all that good to begin with so I have > a question or two. > > Pin 15 is labeled as Expand. Is this an input or an > output? What do you do with it on a CD4048 that is being used as > an 8-input device by itself? > > When cascading multiple gates, do you connect the J > output pin to the Expand pin of the following gate? > > The rest, I think I can figure out. Hu rah for wire-wrap! > http://www.chipdir.org/giicm/4048.txt It's an 'or' or a 'nor' gate. Use OR & invert your main output. Connect 8-16 into any input for a 15 input gate. To make 16, you'd need an extra 'or' gate. That's how it seems to me. -- Regards, Declan Moriarty Applied Researches - Ireland's Foremost Electronic Hardware Genius A Slightly Serious(TM) Company Without the optimist, the pessimist wouldn't know how happy he isn't -- Author: Declan Moriarty INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Author: Ghanekar, Girish (IE03x) INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB CHIPDIR-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
