Transistor-Transistor TTL Logic and Totem pole output

Started by Patrick Chung in sci.electronics.design5 years ago 7 replies

By combining basic TTL Logic NAND gate with invertors and other gate any logical function can be realized in TTL technology. TTL family of logic...

By combining basic TTL Logic NAND gate with invertors and other gate any logical function can be realized in TTL technology. TTL family of logic circuits is specially empowered with TTL Totem pole output Read more: http://www.cirvirlab.com/index.php/electronic/181-transistor-transistor-ttl-logic.html


Interesting feature of an inexpensive function generator

Started by Charles in sci.electronics.design7 years ago 15 replies

Hi, I have been using an GW Instek SFG-2110 and find that the TTL output has a fast rise time. It is about 2 ns and this could be useful for...

Hi, I have been using an GW Instek SFG-2110 and find that the TTL output has a fast rise time. It is about 2 ns and this could be useful for oscilloscope bandwidth measurements for instruments of less than 100 MHz. The TTL option seems to be missing on more expensive function generators. Any thoughts?


Attacking the 35$ (not) computah

Started by Jan Panteltje in sci.electronics.design8 years ago 211 replies

Attacking the 35$ (not) computah. "To get people interested in computers and electronics" Then why not release the datasheet of the chips? A...

Attacking the 35$ (not) computah. "To get people interested in computers and electronics" Then why not release the datasheet of the chips? A circuit diagram, full documentation too. So that is a joke. Sinclair came with the ZX80 in the eighties. It was all TTL chips, and a Z80 processor. Now that was something. The ZX81 had some of that TTL integrated. Diagrams were available, I ev...


Need to construct the logical reverse of a 7448 - perhaps using a GAL

Started by John Robertson in sci.electronics.design2 years ago 44 replies

I am looking for a way to take the TTL level outputs (treating them as inputs) of a 7448 and convert them back to the original BCD TTL input...

I am looking for a way to take the TTL level outputs (treating them as inputs) of a 7448 and convert them back to the original BCD TTL input levels (but as outputs) and I figured a simple socketed GAL would do the trick for the least cost. However I don't have the skill set to build the GAL logic table for this. Any suggestions? And no, I can't simply remove the 7448 from the circuit. ...


Yikes!

Started by John Larkin in sci.electronics.design8 years ago 77 replies
TTL

I found myself still using my yellow "The TTL Data Book for Design Engineers", second edition, from 1976. John

I found myself still using my yellow "The TTL Data Book for Design Engineers", second edition, from 1976. John


Favorite jellybean ~HF BJT?

Started by Tim Williams in sci.electronics.design11 years ago 13 replies

2N2369 is an old standby... kind of high current (200mA), like a '3904 sped up about 2-3 times. Not well specified though, I suppose because...

2N2369 is an old standby... kind of high current (200mA), like a '3904 sped up about 2-3 times. Not well specified though, I suppose because it's so old. I'm thinking in the 20V, 50mA range, fT maybe 0.5-1GHz. Like if you wanted to make old school RTL circuits that run as fast as 74S TTL. MPSH11 looks good, and '81 looks like its complement. I've used PN3563 before (complement PN425...


How to double PCI clock?

Started by Johann Klammer in sci.electronics.design5 years ago 9 replies

Classical 5V PCI, that is. Is there a small IC for this? I need a 66 Mhz clock generated from the 33Mhz of the PCI bus, but can not seem to...

Classical 5V PCI, that is. Is there a small IC for this? I need a 66 Mhz clock generated from the 33Mhz of the PCI bus, but can not seem to find an IC that is specified for the PCI input spikes of 11V. Also, most seem to be cmos parts that have the input thresholds at vcc/2 instead of the lower TTL levels.


Good Replacement for 4052 Analog Mux.

Started by Anonymous in sci.electronics.design5 years ago 7 replies
TTL

Looking for a cost effective part that is better then the classic 4052 switch. Requirements: Rugged part that can handle being used by...

Looking for a cost effective part that is better then the classic 4052 switch. Requirements: Rugged part that can handle being used by hobbyists. Dip package preferred for customer replacement. +/- 12 to 15V rails. TTL Control +/- 5V signal, DC to 3 KHz waveforms. Steve


pc motherboard grounds

Started by John Larkin in sci.electronics.design8 years ago 115 replies

The mounting holes on PC motherboards: are they usually connected to the PCB ground plane? -- John Larkin ...

The mounting holes on PC motherboards: are they usually connected to the PCB ground plane? -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL d...


Bucket List

Started by John Larkin in sci.electronics.design7 years ago 3 replies

43. PRESIDENT OF EGYPT OK, I'm thinking about striking that one off. -- John Larkin Highland Technology...

43. PRESIDENT OF EGYPT OK, I'm thinking about striking that one off. -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME an...


Xenon flash tube

Started by bitrex in sci.electronics.design5 years ago 42 replies

I got several of these xenon flash tubes down at Rat Shack on sale for less than 2 bucks...

I got several of these xenon flash tubes down at Rat Shack on sale for less than 2 bucks each. http://www.radioshack.com/long-life-xenon-strobe-tube/2721145.html Anyone have a design for a junk box circuit that could be used for experimenting with these, say firing them from a TTL logic output?


555 timer

Started by George Herold in sci.electronics.design9 years ago 41 replies

Hey, I think I=92ve got a use for a few dual 555 timers. (First time in ~20 years) I want to make some signal sources with a max freq. of maybe...

Hey, I think I=92ve got a use for a few dual 555 timers. (First time in ~20 years) I want to make some signal sources with a max freq. of maybe 100kHz. (I figure I=92ll heavily RC filter the output) I was going to order the CMOS version (TS556). Is there any reason to use the TTL one? (NE556) The minuscule cost difference makes no difference to me. Thanks, George H.


hurricanes

Started by John Larkin in sci.electronics.design7 years ago 51 replies

http://stevengoddard.files.wordpress.com/2013/05/screenhunter_19-may-08-06-04.jpg -- John Larkin Highland...

http://stevengoddard.files.wordpress.com/2013/05/screenhunter_19-may-08-06-04.jpg -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links ...


brogrammer

Started by John Larkin in sci.electronics.design8 years ago 11 replies

Google that! -- John Larkin, President Highland Technology, Inc jlarkin at highlandtechnology dot...

Google that! -- John Larkin, President Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser controllers Photonics and fiberoptic TTL data links VME thermocouple, LVDT, synchro acquisition and simulation


LV/5V level shifting using 74HC gates

Started by Bruce Varley in sci.electronics.design8 years ago 27 replies
TTL

I need to convert LV (3.3v rail) signals to TTL levels (5V rail). My present arrangement is to feed the LV to 74HC04 inputs, with a 5v supply on...

I need to convert LV (3.3v rail) signals to TTL levels (5V rail). My present arrangement is to feed the LV to 74HC04 inputs, with a 5v supply on the 74HC04. That looks like it should be OK from the device datasheet, but I've experienced one runaway, the chip got smoking hot. Could this be caused by the fact that the inputs are not getting close enough to the rail voltage when they're hig...


NIF

Started by John Larkin in sci.electronics.design8 years ago 20 replies

http://www.theregister.co.uk/2012/07/16/nif_passes_500_trillion_watts/ -- John Larkin Highland Technology...

http://www.theregister.co.uk/2012/07/16/nif_passes_500_trillion_watts/ -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, t...


LED reference current source

Started by John Larkin in sci.electronics.design8 years ago 286 replies

Has anybody done this? https://dl.dropbox.com/u/53724080/Circuits/Isrc_LED.JPG -- John Larkin Highland Technology...

Has anybody done this? https://dl.dropbox.com/u/53724080/Circuits/Isrc_LED.JPG -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links V...


NEWS

Started by John Larkin in sci.electronics.design7 years ago 7 replies

http://dailycurrant.com/ -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at...

http://dailycurrant.com/ -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME analog, thermocouple, LVDT, synchro, tachometer Multic...


Danish Butter Cookies

Started by John Larkin in sci.electronics.design7 years ago 42 replies

The tins are great for keeping all of a project's stuff together on the workbench. -- John Larkin Highland Technology,...

The tins are great for keeping all of a project's stuff together on the workbench. -- John Larkin Highland Technology, Inc jlarkin at highlandtechnology dot com http://www.highlandtechnology.com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom laser drivers and controllers Photonics and fiberoptic TTL data links V...


Phil

Started by John Larkin in sci.electronics.design7 years ago 8 replies

https://dl.dropboxusercontent.com/u/53724080/Circuits/Amps/Compound_Fet.JPG -- John Larkin Highland Technology...

https://dl.dropboxusercontent.com/u/53724080/Circuits/Amps/Compound_Fet.JPG -- John Larkin Highland Technology Inc www.highlandtechnology.com jlarkin at highlandtechnology dot com Precision electronic instrumentation Picosecond-resolution Digital Delay and Pulse generators Custom timing and laser controllers Photonics and fiberoptic TTL data links VME anal...