J
Jamie
Guest
George Herold wrote:
Jamie
Put a 50 ohm R across your gen output..
Jamie
J
John Larkin
Guest
On Wed, 25 Jan 2012 12:46:43 -0800 (PST), George Herold
<gherold@teachspin.com> wrote:
probably isn't fast enough to excite something like that. Still, it's
probably lead lengths or something causing all that ringing.
John
<gherold@teachspin.com> wrote:
That ringing is about 40 MHz. The edge from my function generator
probably isn't fast enough to excite something like that. Still, it's
probably lead lengths or something causing all that ringing.
John
J
Jamie
Guest
John Larkin wrote:
Also, I've seen problems with lack of shoot through on complemary
emitter followers as unity buffers on equipment exhibiting this effect.
A non reactive fixed load on the output normally fixes this. Ringing
can be suppressed if the device that is delivering the signal
has a high gain loop back and enough current handling to counter the
reaction.
Many signal generators do not have feed back on their final stage to
help the driving circuit maintain the output.
I've designed amplifiers to drive magnetic scan and focus coils and
one of the items in the design is to have the amplifier attempt to
counter act any reactive response, other wise, it'll show in the sweeps
and focusing.
That's my take on it
Jamie
properly terminated to bring the Q down to 1 or less.
Also, I've seen problems with lack of shoot through on complemary
emitter followers as unity buffers on equipment exhibiting this effect.
A non reactive fixed load on the output normally fixes this. Ringing
can be suppressed if the device that is delivering the signal
has a high gain loop back and enough current handling to counter the
reaction.
Many signal generators do not have feed back on their final stage to
help the driving circuit maintain the output.
I've designed amplifiers to drive magnetic scan and focus coils and
one of the items in the design is to have the amplifier attempt to
counter act any reactive response, other wise, it'll show in the sweeps
and focusing.
That's my take on it
Jamie
J
John Larkin
Guest
On Wed, 25 Jan 2012 11:35:08 -0600, Tim Wescott <tim@seemywebsite.com>
wrote:
Does this work?
http://dl.dropbox.com/u/53724080/Circuits/Tant_ESR_Rig.JPG
http://dl.dropbox.com/u/53724080/Circuits/Tant_ESR_Scope.JPG
The web site needs work, and it's kind of a nuisance to throw files up
onto. The FTP is really fast and easy, but some people can't see it.
John
wrote:
Does this work?
http://dl.dropbox.com/u/53724080/Circuits/Tant_ESR_Rig.JPG
http://dl.dropbox.com/u/53724080/Circuits/Tant_ESR_Scope.JPG
The web site needs work, and it's kind of a nuisance to throw files up
onto. The FTP is really fast and easy, but some people can't see it.
John
J
Jamie
Guest
John Larkin wrote:
btw, I have the 100mhz version, not the software hacked 50mhz, if
that makes any difference?
Jamie
yellow? Or is that the natural color? my Rigol is near white.
btw, I have the 100mhz version, not the software hacked 50mhz, if
that makes any difference?
Jamie
J
Jim Thompson
Guest
On Mon, 23 Jan 2012 06:22:25 -0600, Lostgallifreyan
<no-one@nowhere.net> wrote:
The data sheet is amongst the worst I've ever seen.
Can you collect the following data:
(1) Unloaded supply current versus total supply voltage
(2) Maximum SINK current capability versus total supply voltage
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
<no-one@nowhere.net> wrote:
The data sheet is amongst the worst I've ever seen.
Can you collect the following data:
(1) Unloaded supply current versus total supply voltage
(2) Maximum SINK current capability versus total supply voltage
...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice
480)460-2350 Fax: Available upon request | Brass Rat || E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
J
John Larkin
Guest
On Wed, 25 Jan 2012 20:04:38 -0500, Jamie
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
No. I'd never hire anybody who smokes.
why is that scope so
camera is set for daylight mode or something. But you're supposed to
be admiring the fabulous waveform, not the photography.
bandwidth. That's fine for most of what I do. If it's not, there's my
20 GHz 11801 right beside it.
John
<jamie_ka1lpa_not_valid_after_ka1lpa_@charter.net> wrote:
No. I'd never hire anybody who smokes.
why is that scope so
The Rigol is a little off-white, a faint cream color. Probably the
camera is set for daylight mode or something. But you're supposed to
be admiring the fabulous waveform, not the photography.
This one isn't hacked. Risetime measures 5.6 ns, which is a 63 MHz
bandwidth. That's fine for most of what I do. If it's not, there's my
20 GHz 11801 right beside it.
John
G
George Herold
Guest
On Jan 25, 6:21 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
signal and too much noise... pickup... My lab bench seems to live in a
bath of 100MHz.
I was thinking after bad mouthing my x1 probes I now have to dig one
out.
George H.
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
Yeah, the sharp edge. I tried the x10 probe but there was too little
signal and too much noise... pickup... My lab bench seems to live in a
bath of 100MHz.
I was thinking after bad mouthing my x1 probes I now have to dig one
out.
George H.
J
John S
Guest
On 1/25/2012 11:35 AM, Tim Wescott wrote:
Try: copy the link and paste into browser address bar.
Tim -
Try: copy the link and paste into browser address bar.
J
John S
Guest
On 1/25/2012 4:57 PM, Jamie wrote:
you asking a question Dip Shit?
The question mark indicates you don't know whether it does or not. Are
you asking a question Dip Shit?
J
Jamie
Guest
John Larkin wrote:
Jamie
Yeah, forgot, the wave form looks nice
Jamie
J
John Larkin
Guest
On Wed, 25 Jan 2012 19:48:03 -0800 (PST), Tim Williams
<tmoranwms@gmail.com> wrote:
Does this involve tantalum caps?
John
<tmoranwms@gmail.com> wrote:
I don't exactly understand the situation. Got a sketch?
Does this involve tantalum caps?
John
J
John Larkin
Guest
On Wed, 25 Jan 2012 20:07:30 -0800 (PST), Tim Williams
<tmoranwms@gmail.com> wrote:
Have you tried this?
http://tinyurl.com/7xqed3l
Once you sip this, cognac has no purpose any more.
Stick with ceramics, or if you really need a lot of C, use a polymer
aluminum.
John
<tmoranwms@gmail.com> wrote:
Have you tried this?
http://tinyurl.com/7xqed3l
Once you sip this, cognac has no purpose any more.
I wouldn't use a tantalum cap here. Current is what detonates them.
Stick with ceramics, or if you really need a lot of C, use a polymer
aluminum.
John
T
Tim Williams
Guest
On Jan 24, 10:58 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
I have 8 channels in parallel, supplied from a single current-limited
supply. But the thing is, if the current from 8 channels at full
power, flows into one channel as fault current, that's four amperes
more than it was designed to run... Ever had a case like this?
What's the best way to handle it?
Tim
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
Now, the funny thing I've got right now:
I have 8 channels in parallel, supplied from a single current-limited
supply. But the thing is, if the current from 8 channels at full
power, flows into one channel as fault current, that's four amperes
more than it was designed to run... Ever had a case like this?
What's the best way to handle it?
Tim
T
Tim Williams
Guest
On Jan 25, 9:55 pm, John Larkin
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
Yes -- I have eight output transformers in parallel from the same
current-limited PWM driver. Now, under normal conditions, all eight
channels are working correctly, so the current shares evenly, and all
the caps are happy (the maximum supply is 5A, so they each see a
maximum of 5A / 8 = 0.6A peak, so the RMS ripple is under 0.42A, fine
for a chip tantalum, though I have ceramic specified at the moment).
But under fault, the whole 5A could flow into just one channel, which
makes things "interesting". I may implement a "max-of-channels"
current limit for this.
Tim
<jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
A description should suffice [rum disclaimer inserted here]:
Yes -- I have eight output transformers in parallel from the same
current-limited PWM driver. Now, under normal conditions, all eight
channels are working correctly, so the current shares evenly, and all
the caps are happy (the maximum supply is 5A, so they each see a
maximum of 5A / 8 = 0.6A peak, so the RMS ripple is under 0.42A, fine
for a chip tantalum, though I have ceramic specified at the moment).
But under fault, the whole 5A could flow into just one channel, which
makes things "interesting". I may implement a "max-of-channels"
current limit for this.
Tim
L
Lostgallifreyan
Guest
Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote in
news:1ia1i7t48tsitavjukpdub0jn0o1mukk5l@4ax.com:
different sources, each set up as a voltage follower: wire links from Out
back to -In, +in to V- rail. The output was unloaded. 33 readings for each
IC. This data set may well be overkill, but I want quality so I have to give
it. It takes some endurance and patience with my setup to get stable
readings this accurate, so I'll sleep before I try for the sink currents.
Is there any change I must make to that voltage follower circuit I described
just now, for the sink current tests? Also, I assumed I'd have to limit the
current in whatever was on the output to prevent damage to the output, so I
don't understand what is needed to set up that test. (Might if I was less
tired, but please save me from a silly mistake tomorrow, as I have callers
to measure up fencing and cracked glass, plenty of distractions....)
TABLES OF 3 CA1410 IC'S, IDLE CURRENT DRAW AT BETWEEN 4VDC AND 26VDC.
(Current measured on 40 mA range of Fluke 79, series II).
(Voltage measured simultaneously on Fluke 77, series II).
V mA
Sample 1:
4.02 1.216
5.01 1.302
6.00 1.383
7.00 1.466
8.01 1.550
9.01 1.632
10.01 1.711
11.01 1.789
12.01 1.866
13.01 1.944
14.00 2.020
15.00 2.095
16.01 2.172
17.01 2.249
18.01 2.324
19.01 2.398
20.00 2.471
21.01 2.546
22.01 2.620
23.00 2.692
24.00 2.765
25.01 2.837
26.01 2.908
27.01 2.979
28.00 3.048
29.00 3.118
30.01 3.190
31.00 3.258
32.01 3.328
33.00 3.401
34.00 3.469
35.00 3.538
36.00 3.601
Sample 2:
4.00 1.331
5.00 1.446
6.01 1.535
7.01 1.621
8.00 1.706
9.01 1.789
10.00 1.868
11.01 1.946
12.00 2.022
13.01 2.100
14.00 2.174
15.01 2.249
16.01 2.268
17.01 2.294
18.00 2.370
19.01 2.446
20.01 2.521
21.00 2.595
22.01 2.670
23.01 2.744
24.00 2.817
25.00 2.889
26.01 2.962
27.00 3.031
28.00 3.104
29.01 3.174
30.00 3.242
31.01 3.314
32.01 3.384
33.00 3.456
34.00 3.522
35.00 3.588
36.00 3.655
Sample 3:
4.00 1.250
5.01 1.333
6.00 1.391
7.01 1.075
8.01 1.559
9.01 1.644
10.00 1.722
11.01 1.802
12.00 1.879
13.00 1.958
14.01 2.036
15.00 2.113
16.01 2.191
17.01 2.268
18.00 2.341
19.01 2.418
20.01 2.493
21.00 2.567
22.00 2.642
23.00 2.716
24.01 2.790
25.01 2.863
26.01 2.936
27.00 3.007
28.01 3.079
29.01 3.148
30.00 3.218
31.01 3.287
32.01 3.357
33.00 3.431
34.00 3.495
35.00 3.562
36.00 3.632
news:1ia1i7t48tsitavjukpdub0jn0o1mukk5l@4ax.com:
I got three samples of Intersil CA3140, of various ages, likely from
different sources, each set up as a voltage follower: wire links from Out
back to -In, +in to V- rail. The output was unloaded. 33 readings for each
IC. This data set may well be overkill, but I want quality so I have to give
it.
It takes some endurance and patience with my setup to get stable readings this accurate, so I'll sleep before I try for the sink currents.
Is there any change I must make to that voltage follower circuit I described
just now, for the sink current tests? Also, I assumed I'd have to limit the
current in whatever was on the output to prevent damage to the output, so I
don't understand what is needed to set up that test. (Might if I was less
tired, but please save me from a silly mistake tomorrow, as I have callers
to measure up fencing and cracked glass, plenty of distractions....)
TABLES OF 3 CA1410 IC'S, IDLE CURRENT DRAW AT BETWEEN 4VDC AND 26VDC.
(Current measured on 40 mA range of Fluke 79, series II).
(Voltage measured simultaneously on Fluke 77, series II).
V mA
Sample 1:
4.02 1.216
5.01 1.302
6.00 1.383
7.00 1.466
8.01 1.550
9.01 1.632
10.01 1.711
11.01 1.789
12.01 1.866
13.01 1.944
14.00 2.020
15.00 2.095
16.01 2.172
17.01 2.249
18.01 2.324
19.01 2.398
20.00 2.471
21.01 2.546
22.01 2.620
23.00 2.692
24.00 2.765
25.01 2.837
26.01 2.908
27.01 2.979
28.00 3.048
29.00 3.118
30.01 3.190
31.00 3.258
32.01 3.328
33.00 3.401
34.00 3.469
35.00 3.538
36.00 3.601
Sample 2:
4.00 1.331
5.00 1.446
6.01 1.535
7.01 1.621
8.00 1.706
9.01 1.789
10.00 1.868
11.01 1.946
12.00 2.022
13.01 2.100
14.00 2.174
15.01 2.249
16.01 2.268
17.01 2.294
18.00 2.370
19.01 2.446
20.01 2.521
21.00 2.595
22.01 2.670
23.01 2.744
24.00 2.817
25.00 2.889
26.01 2.962
27.00 3.031
28.00 3.104
29.01 3.174
30.00 3.242
31.01 3.314
32.01 3.384
33.00 3.456
34.00 3.522
35.00 3.588
36.00 3.655
Sample 3:
4.00 1.250
5.01 1.333
6.00 1.391
7.01 1.075
8.01 1.559
9.01 1.644
10.00 1.722
11.01 1.802
12.00 1.879
13.00 1.958
14.01 2.036
15.00 2.113
16.01 2.191
17.01 2.268
18.00 2.341
19.01 2.418
20.01 2.493
21.00 2.567
22.00 2.642
23.00 2.716
24.01 2.790
25.01 2.863
26.01 2.936
27.00 3.007
28.01 3.079
29.01 3.148
30.00 3.218
31.01 3.287
32.01 3.357
33.00 3.431
34.00 3.495
35.00 3.562
36.00 3.632
L
Lostgallifreyan
Guest
Lostgallifreyan <no-one@nowhere.net> wrote in
news:Xns9FE63BF8B1BB6zoodlewurdle@216.196.109.145:
news:Xns9FE63BF8B1BB6zoodlewurdle@216.196.109.145:
It will be obvious, but that should be 36VDC.
L
Lostgallifreyan
Guest
Lostgallifreyan <no-one@nowhere.net> wrote in
news:Xns9FE63BF8B1BB6zoodlewurdle@216.196.109.145:
Maybe worth mentioning the ambient temperature: 21°C. Same for all three idle
current tests.
news:Xns9FE63BF8B1BB6zoodlewurdle@216.196.109.145:
Maybe worth mentioning the ambient temperature: 21°C. Same for all three idle
current tests.
L
Lostgallifreyan
Guest
I looked at the Intersil datasheet and saw a graph for idle current vs
voltage that suggested my readings were half what they should be! As the
milliamp range on a meter is the most easily damaged, I did a simple test to
see what if any scale change should be made to my readings to get accuracy
from them.
3.802V across Li-ion cell loaded by 996 ohms.
Calculated current: 3.776mA.
Actual current: 3.817mA.
Not as close as they should be, but much closer than the difference between
datasheet graphs and measured values.
voltage that suggested my readings were half what they should be! As the
milliamp range on a meter is the most easily damaged, I did a simple test to
see what if any scale change should be made to my readings to get accuracy
from them.
3.802V across Li-ion cell loaded by 996 ohms.
Calculated current: 3.776mA.
Actual current: 3.817mA.
Not as close as they should be, but much closer than the difference between
datasheet graphs and measured values.
M
Martin Brown
Guest
John Larkin wrote:
want to and then publish their URL. Try creating a directory "temp" or
even "ftp" on your website and treat it like you do with ftp:://
Then you can ftp stuff up and others can look at it how they like.
Regards,
Martin Brown
Yes. These are much more user friendly to the outside world.
You should be able to throw files up onto your website by ftp if you
want to and then publish their URL. Try creating a directory "temp" or
even "ftp" on your website and treat it like you do with ftp:://
Then you can ftp stuff up and others can look at it how they like.
Regards,
Martin Brown