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TTL
Sci.Electronics.Design is a worldwide Usenet news group that is used to discuss various aspects of Electronic Circuit Design.
We found 146 threads matching "ttl"
You are looking at page 1 of 4.
The most relevant threads are listed first
Testing a TTL chip
2009-02-15 16:39:00
I am trying to figure out if a TTL chip of mine (for my science fair -
see "Vacuum Tube Calculator Schematic" for more) to see if I burned it
out. It's a 7474, and I've connected the ~PRESET inputs directly to
+5V because I do not want to be setting it (only reseting it). Did I
do something wron...
TTL signal
2008-12-09 15:11:00
I'm trying to convert an analog signal, 150mV, 3-5nS pulse width to a
TTL signal.
...3 phase motor driver
GregS - 2008-11-26 10:50:00
I have been fishing through drivers hoping to find something.
Anyone know of a 3 phase mosfet driver module
with TTL in and the old board used a 170 VDC supply or rectified 120 line.
probably less than 10 amps. I have seen pieces, but
looking for an integrated module. The control circuitry
is i...Re: 8 Bit number to 3 seperate 7-segment LED displays
Paul Burke - 2008-01-08 11:44:00
Sean Brown wrote:
> Good afternoon,
>
> I was wondering if anyone can give me some ideas on how to take an 8-
> bit number and display it on 3 LED displays.
>
> I would be extremely grateful if you could give me a push in the right
> direction.
I used to know several methods of do...Re: Compuserve closing, need to relocate website
Nobody - 2009-04-24 18:42:00
On Fri, 24 Apr 2009 09:53:57 -0700, Joel Koltner wrote:
> > I don't imagine there can be more than one location for any domain
> > name, so if I want to move someplace else, do I have to close the old
> > account first and then setup the new?
>
> The important thing to know here is that...LVTTL to RS-232 adaptor
2008-05-29 06:16:00
Hello,
I am looking for a LVTTL to RS-232 adaptor.
I found a similar adaptor http://www.hvwtech.com/products_view.asp?ProductID=289
But this adoptor does TTL to RS-232.
Since I plan to convert the LVTTL output from a Virtex-4 FPGA to
RS-232 signal, I need LVTTL to RS-232 adaptor.
Virtex-...Simple SD Interface
FyberOptic - 2010-01-07 11:09:00
Hi folks. Maybe I'll try this here since the electronics.basics
newsgroup is fairly inactive these days apparently.
Anyhow, I want to do something fairly simple, but I want the advice of
someone who actually knows more about this stuff to make sure I don't
do something wrong that I'm not taki...Re: MAx232 unused inputs
petrus bitbyter - 2010-01-06 09:29:00
"lighthouseman" schreef in bericht
news:9885e2a0-1802-483c-b9e8-147d1a110a1c@j14g2000yqm.googlegroups.com...
> Here's a nice simple one for you....
> If my design has 5 CMOS serial ports, and I use something like 3 x
> MAX232, which have 2 drivers/receivers on each chip, then what shoul...Re: A digital design question
Bob Eld - 2010-01-13 11:11:00
"Bitrex" wrote in message
news:Qq6dnXrFS-I2KtDWnZ2dnUVZ_s2dnZ2d@earthlink.com...
> I'm playing around with some 7400 series logic, trying to teach myself
> the basics of digital design. I've been able to come up with a working
> circuit for a 24 hour digital clock easily, but I'm strugg...Re: Cascading two 74LS90's doesn't work (needs deglitching)
Arie - 2008-04-26 07:52:00
"Rocky" wrote in message
news:68d837c4-9528-4982-872f-2d90a7943691@h1g2000prh.googlegroups.com...
> So now I need to alleviate reflections causing the multiple triggers.
> Do people have suggestions as to how I do that ?
ALWAYS use buffers and terminators to drive cables (or "electrical...Re: current-mode opamps
Jim Thompson - 2008-02-27 09:58:00
On Tue, 26 Feb 2008 21:30:20 -0800, John Larkin
wrote:
> On Tue, 26 Feb 2008 20:48:30 -0800, "Jim Thompson"
> wrote:
>
> >
> > "John Larkin" wrote in message
> > news:4te8s3h7h4037d3mgmqcroh4a9au5npndk@4ax.com...
> > > On Tue, 26 Feb 2008 11:29:06 +0100, Fred Bartoli wrote:...High Speed Driver?
Vladimir Vassilevsky - 2009-03-17 10:10:00
I need to generate the accurate waveform from TTL input. The swing
should be ~20Vpp, slew rate > 1kV/us, load current ~5mA, top and bottom
tied to the reference voltage. The switch like that can certainly be
done with few discrete components, however I wonder if there is a single
IC solut...looking for a transistor
2008-01-01 16:48:00
I need to switch some GE #44 lamps from a TTL output. #44 lamps are 6.3 volts
at 250 ma, so I'll need a transistor to do the real work. Unfortunately, it's
just a hair too much power for one of the hundreds of surplus 2n2222's I keep
around to do almost everything else here. Can someone sugges...Re: D82C55AC-2
Rich Grise - 2008-05-20 20:05:00
On Tue, 20 May 2008 12:09:03 -0700, aleksa wrote:
> I've bought 10 pcs of "82C55" through mail, and received D82C55AC-2.
>
> The problem is that the output high voltage of any pin is not 5V, but
> 3.8V.
>
> Nothing is connected to the port pins, VCC is 4.85V.
>
> Am I wrong thin...6800 clock generator circuit
rombios - 2009-01-19 23:23:00
curse the 6800 the 6802,6803 were much easier to play with. Onboard clock
generators for phase1 and phase2, I simply had to provide a ttl
compatible signal as clock input or rig up a crystal
does anyone have a clean/simple clock generator logic for the 6800 thats
meets its requirements (no...SPDIF to AES/EBU
Dirk Bruere at NeoPax - 2010-03-02 16:49:00
Looking for a reliable circuit for the level conversion from SPDIF to
TTL. I then intend to feed it to an RS485 driver and into a transformer
for transmission via CAT5e
--
Dirk
http://www.transcendence.me.uk/ - Transcendence UK
http://www.theconsensus.org/ - A UK political party
http:/...Re: Non-Scientific Survey of Scientific Calculators
John Fields - 2008-02-01 18:35:00
On Fri, 01 Feb 2008 12:39:56 -0800, John Larkin
wrote:
> Right about that time I got an HP35 for $400. I still have it.
---
Back then, I got one of these:
http://www.hpmuseum.org/3qs/973q.jpg
which I also still have.
---
> I also
> got a PDP-11, which taught me how to think...Re: How to interface a microcontroller to fibre optic?
StoneThrower - 2009-03-30 15:11:00
> Where can I find more information about interfacing microcontroller to
> fibre optics?
A possible solution - TTL-to-FO link or converter
1st read this: Cypress, AN13853, http://www.cypress.com/?docID=2349
then look after FO drivers mentioned in above AN, from OPTEK Technologies,
http://w...Re: Z80 CP/M SBC design project
Frank Buss - 2008-07-28 15:58:00
lynchaj wrote:
> It is a opportunity to educate people about home brew computing and
> the history of computing electronics.
Real men don't use boutique chips like Z80, but only standard TTL for
building a computer:
http://www.homebrewcpu.com/backplane1.htm
--
Frank Buss, fb@frank-...Re: Using CMOS logic for amplifying small signals
Vladimir Vassilevsky - 2008-01-04 12:30:00
Mr. B wrote:
> Something has occurred to me, and I was wondering if anyone knew more about
> this. Could a CMOS logic inverter, like a 4049, be used as a very high
> gain amplifier if it were properly biased?
Using TTL and CMOS logic IC as the linear amplifiers used to be a
textboo...Re: Driving a piezo sounder
Scott Seidman - 2008-06-05 19:47:00
Martin Griffith wrote in
news:00dg449i60rbpcch0qr51n4qcij1de4mfv@4ax.com:
> I've just got back to thinking how to drive piezo sounder, and was
> wondering if something like the Natsemi LM4908 headphone amp working
> in bridge mode would be ok.
> The piezo has a 18nF capacitance
> T...Re: Influenced by Science Fiction
Jasen Betts - 2009-01-04 04:33:00
On 2009-01-03, Frank Buss wrote:
> Dirk Bruere at NeoPax wrote:
>
> > As they say in the script: "It's a VR simulation in the cyberspace
> > representation of the networked microprocessor GPS system PCB." Or
> > something.
>
> And why do they throw some wires in the box, first, wh...Favorite jellybean ~HF BJT?
Tim Williams - 2009-12-17 13:33:00
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. ...Re: PWM dsPIC33F
Pasquale - 2008-05-21 19:26:00
> You want *code* now? Sorry, posting code would be completely off-topic
> here and I could be strung up by my bolo tie. Hint: You can usually
> change the PWM to regular port pins (and back) on the fly.
>
>
> Best regards,
> Spehro Pefhany
I don't want any code. I agree with your ...Tiny logic-controlled high-voltage buffers?
Joel Koltner - 2009-01-19 16:48:00
We often have something like a 5V or 3.3V logic line coming from an FPGA or
microcontroller that needs to drive something like a 28V bias line to an RF
PIN diode or some RF amplifier's power supply or what-not... and in generally
we do this with a couple of FETs and a resistors or two, and it ...200 volt SPDT solid state switch needed
Steve - 2009-05-20 11:06:00
I need a SPDT solid state switch that can handle 200 volts on one pole
and 0 volts on its other and be switched by TTL. I have up to 10 mA
available to drive the switch. Switch output current is low ( < 1 mA)
and switching speed can be slow (1 msec). Ideally, 4 or 8 on one chip
would be nice ...fast pulse radio transmission
sergio108 - 2008-05-08 08:14:00
Hi All.
I want to find a transmitters-receivers or transceiver can be used in
our project.
We are developing a project where we need to send and receive random
asynchronous digital TTL pulses (5 to 10 microsecond wide) without
delay trough RF at a variable rate from 10000 (1e4) to 100000 (1e5)
...Re: Thermostat + Timer
ChrisQ - 2009-10-15 11:19:00
Jan Panteltje wrote:
>
> You can make a nice zero crossing power switch for 240 V with a MOC3041,
> driving a TIC263M triac, that one can do 25 A continuous (use heatink).
> The MOC3041 needs 15 mA, PIC can drive that, the MOC3042 10mA, and the MOC3043 needs only 5mA.
> Just did one las...Re: SD-24 guts
ChrisQ - 2009-11-03 16:37:00
John Larkin wrote:
>
> These Tek 11801-type scopes sometimes throw an error on powerup and
> while running. Many of them just go away.
>
> John
>
If they have microprocessor control, another thing to watch out for is
the static ram chips in some early micro controlled test gea...Re: OT: SLR Cameras
Jim Yanik - 2010-02-28 08:56:00
"Martin Riddle" wrote in
news:hmc6ef$ent$1@news.eternal-september.org:
>
>
> "Jim Thompson" wrote
> in message news:entio55mdsac2582pmna8liqea59iuee8u@4ax.com...
> > SLR Cameras... recommendations?
> >
> > ...Jim Thompson
> > --
> ...Re: Advice on Logic Analyzer
2008-04-14 20:29:00
On Apr 14, 1:55 pm, n...@puntnl.niks (Nico Coesel) wrote:
>
> I've used the logic port. It has way to little memory and it is not
> very straightforward to use. If it where my money I would get the
> janatek because it has 1mbit/channel memory.
>
I've experienced that too. It is a nice ...Re: High to Low voltage shifter
2009-05-27 03:45:00
On May 27, 3:44=A0pm, "Electronworks.co.uk"
wrote:
> Hi Jake
>
> When you say 'nmos switch' do you mean an N channel FET? If so, this will
> allow you to interface to a HIGHER voltage (limited by the drain source
> rating of the FET), so 3v3 logic can interface to, say 12V, 24V etc).
...how to design PIN diode driver - high voltage and high speed
Tiger - 2008-07-26 11:30:00
Now i need a high-power T-R switch that can switch state in two
microseconds. Drive outputs: +12 volts(current ,0.5 ampers) , +700
volts , -12volts(-0.5 ampers), -12 volts. Tx path may stand 600
watts
(peak). I want to use PIN driver IC,but don't find IC that may output
+700 volt. So i hav...Re: Analog switch methods
Tim Williams - 2008-12-07 10:09:00
On Dec 6, 3:01=A0pm, chrisgj...@googlemail.com wrote:
> Try a FST3125 or similar, if you don't need more than a volt or two of
> swing. =A0These are cheap, fast, NMOS only switches with built-in gate
> drivers, and the substrate tied to a separate (negative supply rail)
> pin. =A0(You'll hav...Re: DSP Device for Guitar Pedal Effect
ChrisQ - 2009-11-05 06:04:00
krw wrote:
>
> You must have some pretty trivial problems then.
One design was a legacy (1996) counter driven state machine pwm driver
with less than a dozen ttl devices and an eprom. A gate array looked
attractive and would have been a good excuse to get into a bit of vhdl,
but it w...delay line logic
John Larkin - 2009-04-15 16:33:00
One now near-forgotten logic design paradigm is "delay-line logic",
where tapped delay lines were used to sequence digital logic things.
DEC did a lot of this in the PDP-8 days, and early DRAM controllers
tended to work this way. I suppose passive LC delay lines were cheaper
than flipflops and...Re: Problem with current mirrors
John Larkin - 2010-02-25 11:45:00
On Thu, 25 Feb 2010 10:32:58 -0600, "Tim Williams"
wrote:
> "Robert Baer" wrote in message
> news:0fmdneXbU5PE1RvWnZ2dnUVZ_q0AAAAA@posted.localnet...
> > Yes, one DOES lose a little current gain, bit methinks that is not the
> > reason one sees little use of common base circuitry....Re: Nice CdS light detector in col_pic
Phil Hobbs - 2009-04-07 11:21:00
Jan Panteltje wrote:
> On a sunny day (Tue, 07 Apr 2009 10:56:22 -0400) it happened Phil Hobbs
> wrote in
> :
>
> > Leaving a CdS cell out in the sun will make a permanent (or very nearly
> > so) change in cell resistance. The interior of a light meter isn't that
> > bright ev...cmos 74hc debounce pull up resistors
usao - 2008-02-26 14:49:00
I am looking to use a SPDT switch (center GND) with the NO and NC
contacts wired to the inputs of a 74HC00 CMOS NAND gates.
Is it necessary to tie both (NO and NC) inputs to power through a pull-
up resistor? I have seen this done on TTL circuits, but I thought that
the inputs on the CMOS had su...Analog Switch
2008-04-09 16:36:00
I have a DSPT dual single pole double throw analog switch (Dual
channel 2:1 mux/demux). Now I have some questions regarding analog
switches?
1. How do these differ from digital mux which I am faimilar with
(which is basically a selector between multiple inputs based on some
select signals)? W...