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Amplifier
Sci.Electronics.Design is a worldwide Usenet news group that is used to discuss various aspects of Electronic Circuit Design.
We found 857 threads matching "amplifier"
You are looking at page 1 of 22.
The most relevant threads are listed first
Power amplifier
Efthimios - 2008-02-02 11:34:00
Hi
I want to connect a 3800W@8ohms audio amplifier to 4.3kOhms load.
Is the output power of the amplifier for 4.3kohms about 7W???
1. Also if output power is 7W, is the output voltage of the amplifier
Vrms = sqrt(7*4300)= 174 Volt???
2. Is the above calculations correct or the load is ...
high voltage amplifier with wide frequency range
2008-05-14 03:30:00
Hi,
I have to design a high voltage amplifier, that should amplifiy a 3Vpp
sinussodial signal up to 300Vpp. Furthermore the amplifier should work
with linear phase over the whole frequency range from 100kHz to 4 MHz.
The load of the amplifier will be a capacitance from 2pF and a
resistor with...Audio Amplifier
eryer - 2009-09-28 02:09:00
Hi,
I have a little question: in practically all circuits that i have
seen, two voltages are present
1. 3.3V used for DAC
2. 5V used for audio amplifier (in Bridge-tied load configuration)
Why?Is not possible to use the same voltage (3.3V) for DAC and
amplifier?
I don't think it is strictly r...Re: Startable Oscillator
Paul Keinanen - 2009-09-08 06:49:00
On Sun, 6 Sep 2009 01:36:16 -0700 (PDT), Kolja
wrote:
> I need an oscillator circuit that starts immediately with a known
> startup delay from an enable signal.
An oscillator is just an amplifier with feedback satisfying the
Barkhausen criterion, i.e. the losses in the frequency selectiv...need help explaining amplifier noise levels
IAN - 2008-04-07 11:33:00
I am working with an amplifier used in research. The noise level
specifications on the amplifier are listed as:
...10W amplifier, 2.2-2.4GHz
Joel Koltner - 2008-04-10 17:07:00
Anyone have an off-the-shelf 2.2-2.4GHz amplifier they like? ~10W is what I'm
after. Mini-Circuits has their ZHL-30W-252+ which would be fine, although at
$3k I'm continuing to do a bit of searching...
(And before anyone asks, no, I'm not building a high-power WiFi amplifier and,
yes, I d...Pops in audio amplifier
fasf - 2009-10-09 13:44:00
Hi,
i have a little question about pops in audio amplifier....this is the
datasheet of AB amplifier
http://focus.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=tpa6203a1&fileType=pdf
and this is my circuit:
1. TPA6203A1 in single ended configuration (Figure 30 of datasheet)
2....Power output estimation of an Amplifier
Efthimios - 2008-01-17 10:24:00
The power of amplifiers is given in relation to the impedance of the
speakers ( 200W @ 8 ohms).
Since I want to bye an amplifier and connected to a coil with grater
impendence I will need the following info:
Does any of you know how to estimate the power output for grater
impendence of a co...Sense amplifier in SRAMs
radha - 2008-10-31 12:47:00
If a sense amplifier in SRAM is designed for 3v , it cant sense 2v
difference. How can a senseamp can be modified ? Designing the whole
thing again with different devices [FETs] is one obvious solution .
But can it be done in some other better way?
...looking for class D amplifier
Bullwinkle - 2009-09-12 06:21:00
Hi,
i'm looking for a class D amplifier with these specifications:
1. mono
2. max3W
3. gain regulation (varying input pin's logical value and not input
resistor)
Can you help me?
Thanks in advance
...need fm amplifier schematic 5-10 W
Ivan - 2008-01-08 12:01:00
Hello, i am searching for FM amplifier power of 5 to 10 watts, can anyone
give me or suggest what schematic to use, and please, let it be simple. If
is it possible, give me links only to amplifiers who work on 12VDC. Thanks
and sorry on bad english
...Problem with audio amplifier
eryer - 2009-09-16 10:24:00
Hi,
I have a problem with this audio amplifier (i'm new in this field, so
excuse me for my questions):
http://focus.ti.com/lit/ds/symlink/tpa2005d1.pdf
I've used it as single ended amplifier. It is connected to a DAC:
between DAC and IN- a CR high pass filter is present.
DAC can generete signa...opamp differential amplifier high frequency/loading effect
krishmaniac@hotmail.com - 2007-12-21 06:11:00
Hi,
I have a simple difference amplifier based on an opamp. I have few
issues related to its deisgn and analysis.
I have to design it for a differential gain of 10. The gain is decided
by the ratio of the resistors used. R2/R1=R4/R3=10. Normally, what is
the guidelines to select range of resist...Re: Ultra-simple discrete 10W audio power stage for guitar use - would this work?
D from BC - 2008-12-15 03:39:00
I wouldn't do a discrete amplifier at 10W..
Use an amplifier module.
There's many from Digikey and Mouser.
Use the application notes on the datasheets.
D from BC
myrealaddress(at)comic(dot)com
British Columbia
Canada
...Transimpedance amplifier
2009-01-11 17:49:00
Hi,
i've simulated a transimpedance amplifier with spice. My circuit is
composed of an opamp and a feedback resistor; in parallel to current
source a capacitor is present (i want to use a photodiode's equivalent
model). I have a question: is it possible that (with an ac sweep), V/I
transfer fun...Query about designing a linear amplifier using CMOS inverter
Mandar - 2008-01-05 11:50:00
Hi everyone,
Here I have a problem in using CMOS inverter as an amplifier.
What should be the consideration while choosing the resistance value
of the feedback resistor?
I very well know that, it should be of order of few megaohms, but how
many megaohms? Please help.
Thank you.
...Is a parallel amp the same as a balanced amp?
Nick - 2008-05-19 20:41:00
Hello all,
The differences between a parallel amplifier and a balanced amplifier
is rather confusing. Are they the same, or are they different? Both
these circuits, and their advantages, appear to be very close to each
other, if not the same...
Just curious,
-Nick
...40MHz Amplifier.
jim - 2009-07-09 06:44:00
Hi All,
I=92ve built a 40MHz amplifier based on a BLF177 RF FET. The circuit is
similar to the 108MHz class B example presented in the datasheet,
except I have recalculated the input/output matching networks for the
lower frequency. The amplifier works to a point, but performance is
poor. Wit...Re: Noise Measurement
Paul Keinanen - 2009-09-19 00:31:00
On Fri, 18 Sep 2009 11:32:24 -0700 (PDT), john
wrote:
> Hi,
>
> I recently built MOSFET based Bridge Rectifier using NDS9948 and
> FDS9945 MOSFETs using the following circuit
>
> http://www.thetaeng.com/FETBridge.htm
>
> The circuit is working okay. I need to measure the noise in th...Re: Seeking RCA 40428 Germanium Compensating Diode
whit3rd - 2009-11-30 17:45:00
On Nov 29, 12:59=A0pm, Geno Giapasetti wrote:
> For restoring an old receiver, I am looking for at least 4 RCA
> 40428 germanium temperature compensating diodes. Does anyone have any
> suggestions for where I could find some?
Well, RCA had a suggested amplifier using 40421 power transist...Gain parameters of a differential amplifier
deluded.soul@gmail.com - 2008-01-17 15:19:00
Hi everyone,
How can I calculate the gain parameters of a differential amplifier?
I am measuring temperature in the range of 300 degrees and the output
from the amp should be between 0 and 1 V. How can I calculate the gain
factor from this information?
Thanks,
D
...power ampifier
gretsch27 - 2008-03-06 15:08:00
Hi,
I need to build a power amplifier to amplify a signal from a function
generator. I need to give it a sine wave of about 20 Hz and amplify
that to a 100 V amplitude. The application is for a langmuir probe
diagnostic on a plasma generated by a hollow cathode. I need to sweep
voltage from ...glasselectrode input amplifier
wolti_At - 2008-09-17 16:38:00
Hello,
I am currently working on a design where I need to amplify the signal
generated from a glass electrode and a reference electrode. Right now
I have a basic input amplifier with an instrumentation amplifier from
analog devices working. The challenging task on these designs is the
very ...Re: Replacement part needed
whit3rd - 2009-02-03 16:51:00
On Feb 3, 8:35=A0am, john wrote:
> INA2133 from TI has an offset voltage of 450uV. Its a 14 pin Chip. I
> am looking for its pin compatible lower offset voltage chip. Ideally,
> I need something lower than 15uV offset voltage.
Redesign to tolerate higher offset voltage.
20 uV per de...[?] Microphony in op-amplifier.
David Chapman - 2009-05-20 17:36:00
Hi,
An audio amplifier for telephone speech in the range 300Hz - 4KHz
which I've built using parts of a quad-op-amplifier (MC33179), is
suffering from microphony. When listening to the output of the amplifier
(with no signals present) and tapping or gently scraping the IC and
adjacen...Re: replace pot on motor controller
hrh1818 - 2008-03-10 11:01:00
On Mar 10, 12:46 am, Craig wrote:
> I have a PWM motor controller that has a 10K pot to adjust the speed.
> I have removed the pot and am wanting to use a 0-5 vdc analog signal
> to change the speed. Hooked up the 0-5 vdc signal in place of the pot
> and the control is backwards i.e. 0 =...On Topic: Distributed amplifier?
Tim Williams - 2010-01-10 00:29:00
How much phase shift is necessary between stages before "a shitload of amps
in parallel" is called "distributed amplifier"? And what is the role of
that phase shift, what does it actually accomplish? Like, why not put a
bunch of amps in a circle and feed their outputs radially towards the ce...Using CMOS logic for amplifying small signals
Mr. B - 2008-01-04 11:48:00
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? I figured that the DC offset
should be set at just about half the supply voltage, so that the gate was
a...class C amplifier gain
Kyle Cronan - 2009-08-22 00:39:00
Hi,
How can I calculate the gain of a class C amplifier with no bias?
These amplifiers often have little or no emitter degeneration, but I
don't see how to figure the intrinsic emitter resistance when there is
no quiescent current. I understand how r_e is derived from Ebers-
Moll, but this a...Design Suggestion Requested
Artist - 2009-03-24 22:38:00
I have a task to design a high voltage linear amplifier. The gain is to
be between 100 and 1000 and the output voltage swing is to be +/-1000 V.
The frequency of operation will be between 10Hz and 500kHz. It will
output single cycle sinewave pulses at a rate of 100Hz. I have never had
to des...Re: Sinusoidal oscillator configuration
Joel Koltner - 2008-08-25 00:12:00
"David L. Jones" wrote in message
news:ed4ee98d-3ea6-451f-ab20-e48d3f849a75@r15g2000prd.googlegroups.com...
> A minimal hardware circuit could be a tiny PIC micro with an RC filter
> - 3 SMD parts.
> Depends on the specs you actually need of course.
I would be surprised if a PIC genera...Switchin Bitchin Audio Amplifier
D from BC - 2009-02-01 22:16:00
Is there a company that makes a totally switchin bitchin amplifier?
What I mean is, smps + class D audio amp.
Perhaps a 100W smps + stereo class D that fits in the palm of my
hand??
Com'on...it's gotta be doable.
Switchin Bitchin Amp < ...Re: Thoughts on AutoTRAX PCB layout software?
Marra - 2008-03-13 17:04:00
On Mar 12, 11:51=A0pm, "Joel Koltner"
wrote:
> "Marra" wrote in message
>
> news:9d8c7c36-02a6-4aaf-8c11-47e0bdf292e3@s37g2000prg.googlegroups.com...
> "I run a disco as well as writing software."
>
> What's the monster heatsink/toroid transformer/control circuitry =A0in the=
PC...Re: Capacitors and ESD
John Larkin - 2010-01-19 00:39:00
On Mon, 18 Jan 2010 23:16:46 -0600, "Tim Williams"
wrote:
> "John Larkin" wrote in message
> news:6udal5t621q5fekd3j96uqlc6h9v1o28oh@4ax.com...
> > > Of course, they'd be no good at bypassing at that voltage. The D-E curve
> > > (think B-H) is going to be flat as Kansas.
> >
> > W...AD8015 - transimpedance amplifier oscillating
2008-03-17 14:45:00
I'm building a optical comm. circuit using an AD8015 transimpedance
amplifier from Analog Devices. Datasheet: http://www.analog.com/UploadedFiles/Data_Sheets/AD8015.pdf
Here is the circuit I'm using: http://gallamine.com/photodiode_tia_schematic.pdf
I'm having trouble with the circuit produci...Re: info of 74hc4051 maximum volatge needed
whit3rd - 2009-03-30 18:31:00
On Mar 30, 2:16=A0pm, michael nikolaou
wrote:
> > > > I want to read many analog inputs from 0....24 V . I want o use one
> > > > multiplexer.
> > > > I think the 74HC4051...
> Can i ask if i use schottky diodes tied to the supply rails so voltage
> is withing +-.2v within the...Re: high-power voltage to current converter
2008-02-23 08:20:00
On Feb 23, 8:14=A0pm, Robert wrote:
> In case it makes things easier, my signal source is actually a
> potentiometer, so if it is more convenient to have resistance rather
> than voltage as the input, it is available. =A0However, the
> potentiometer cannot handle high currents. =A0I was t...Help me calculate the gain parameters of an amplifier
deluded.soul@gmail.com - 2008-01-16 17:47:00
Hi all,
I am having trouble understanding on how to calculate the gain
parameters for an amplifier
So, my card has an input range of 0 to 1 V and I need to measure a
temperature range of 500 degrees.
Now, is the gain calculated completely linearly???
So, the gain factor is 1/500 = 0.00...Xmotors
Kalarama - 2009-03-20 11:23:00
I recently noticed my Crown audio amplifier uses a combination
transformer/motor as the cooling fan. The transformer also feeds
bias/control circuitry.
Neat!
So, if I may presume, if/when the fan motor seizes, the transformer's
primary winding fuse blows, also interrupting +/- 24vdc and ...Cause of audio amplifier failure?
Adrian Tuddenham - 2009-03-13 15:49:00
This circuit (except for D53 & D 54)) has been working in a Compton
Melotone cinema organ for about six months and has given no trouble:
http://www.poppyrecords.co.uk/compton/TrebleAmplifier.gif
A few days ago it failed with both O/P transistors (Tr 61 & Tr 63)
totally short circuited on all...