Switch to reset charge amplifier

Started by Geoffrey in sci.electronics.design8 years ago 19 replies

Hi there I have a charge amplifier, used to amplify the signal from a piezo electric transducer, with 2nF of reference capacitance shunted...

Hi there I have a charge amplifier, used to amplify the signal from a piezo electric transducer, with 2nF of reference capacitance shunted with 1GOhm. I need to be able to reset the amplifier, preferably with a solid state device (the circuit has to be very compact, and operate in a high-vibration environment). One possibility which comes to mind is to simultaneously short the amplifier ou...


Class G amplifier efficiency

Started by amal banerjee in sci.electronics.design8 months ago 21 replies

Could some electronics guru here clarify this a bit ? The efffiiciency definition for an amplifier is Power delivered to load/DC power supplied...

Could some electronics guru here clarify this a bit ? The efffiiciency definition for an amplifier is Power delivered to load/DC power supplied by power source The Dc power supplied from power supply is Vdc x avg. DC current flowing into amplifier However, Vdc changes, as per design requirements of class G amplifier. So what then would be the efficiency defintion for a class G amplifier. ...


Antenna Amplifier Noise Figure

Started by rickman in sci.electronics.design5 years ago 88 replies

I read this post in an antenna group and I don't get how this guy is coming up with a negative noise figure. Looks to me like he is...

I read this post in an antenna group and I don't get how this guy is coming up with a negative noise figure. Looks to me like he is calculating the noise figure of a resistor, not the amplifier. Anyone care to explain this to me? The part that seems bogus is this... > The negative NF is defined as the amplifier noise being less than the > increase in noise due to the amplifier gai


Op-amp differential amplifier

Started by Patrick Chung in sci.electronics.design5 years ago 6 replies

Op-amp differential amplifier has much wider range of input signals comparing to differential amplifier with discrete components. Read...

Op-amp differential amplifier has much wider range of input signals comparing to differential amplifier with discrete components. Read more: http://www.cirvirlab.com/index.php/tutorials/170-op-amp-differential-amplifier-simulation.html and also simulate: http://www.cirvirlab.com/simulation/op-amp-differential-amplifier-online.php


RF amplifier stability question

Started by amal banerjee in sci.electronics.design4 months ago 6 replies

The standard treatment of amplifier stability is based on small signal S parameters, and involves conditional stability, unconditional...

The standard treatment of amplifier stability is based on small signal S parameters, and involves conditional stability, unconditional stability, Rollet's criterion, etc., What about steady state amplifier operation, is there an analytical way to estimate this ?


10W amplifier, 2.2-2.4GHz

Started by Joel Koltner in sci.electronics.design12 years ago 10 replies

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,...

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 do have the appropriate FCC license to put this thing on the air -- with various restrictions on t...


"Efficient" audio amp selection

Started by Don Y in sci.electronics.design9 years ago 24 replies

Hi, I've been designing a "network audio client" (aka "network loudspeaker") and now have to select a suitable amplifier to use in it. 1)...

Hi, I've been designing a "network audio client" (aka "network loudspeaker") and now have to select a suitable amplifier to use in it. 1) The amplifier's presence is "optional" (e.g., when interfacing to external equipment via a "line out", the amplifier is superfluous) 2) The design is intended to support one or two audio channels (e.g., drive a single speaker -- BTL? -- or a pair WH...


Is cklass B amplifier BOTH linear and non-linear

Started by amal banerjee in sci.electronics.design9 months ago 5 replies

Seeking the opinions of gurus on this newsgroup. The bare bones class B amplifier has zero base|gate bias. A class F amplifier is an extension of...

Seeking the opinions of gurus on this newsgroup. The bare bones class B amplifier has zero base|gate bias. A class F amplifier is an extension of the class B with harmonic tuning. So, is class B linear or non-linear.


Regarding amplifier efficiency

Started by amal banerjee in sci.electronics.design10 months ago 7 replies

Could some electronics guru here please clarify this a bit ? I have been experimenting SPICE RF amplifier designs in my spare time,and I am...

Could some electronics guru here please clarify this a bit ? I have been experimenting SPICE RF amplifier designs in my spare time,and I am getting confused by the differences between textbook expressions for amplifier efficiency etc., and my experimental findings. Consider the textbook definition for efficiency as: efficiency = Power delivered to load/DC power supplied First, the p...


HF amplifier purchase

Started by Klaus Kragelund in sci.electronics.design5 months ago 31 replies

Hi I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test Tried to find gear that would do that, but they all have 50 ohms output...

Hi I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test Tried to find gear that would do that, but they all have 50 ohms output Anyone got a link for a amplifier that can do this? Thanks Klaus


Opto in amplifier screws up output

Started by Fibo in sci.electronics.design5 years ago 21 replies

Hello, I'm trying to make a voltage controlled amplifier. I only need a gain of about 11 max. So I thought I would use an opto as a variable...

Hello, I'm trying to make a voltage controlled amplifier. I only need a gain of about 11 max. So I thought I would use an opto as a variable resistor on an inverting amplifier. I went with the H11F3M https://www.fairchildsemi.com/datasheets/H1/H11F3M.pdf I built up the Automatic Gain Control circuit in the datasheet. I used a 50k resistor as my feedback resistor. When I fired it up, my...


Re: Why Adding a Voltage Amplifier after a Transimpedance Amplifier reduce BW? Book Claim by 0.64

Started by Felipe Jimenez in sci.electronics.design5 years ago

On Thursday, May 14, 2015 at 4:08:04 AM UTC-7, Phil Hobbs wrote: > > Oh and I'm fairly certain the non-inverting amplifier is wired up...

On Thursday, May 14, 2015 at 4:08:04 AM UTC-7, Phil Hobbs wrote: > > Oh and I'm fairly certain the non-inverting amplifier is wired up correctly. Between > > switching back and forth from the non-inverting to the inverting configuration > > several times, I am fairly certain that both configurations were wired up properly. > > Hmm... "several times" does make it sound like a


Re: Why Adding a Voltage Amplifier after a Transimpedance Amplifier reduce BW? Book Claim by 0.64

Started by John Larkin in sci.electronics.design5 years ago

On Thu, 14 May 2015 04:07:59 -0700 (PDT), Phil Hobbs wrote: > > Oh and I'm fairly certain the non-inverting amplifier is wired up...

On Thu, 14 May 2015 04:07:59 -0700 (PDT), Phil Hobbs wrote: > > Oh and I'm fairly certain the non-inverting amplifier is wired up correctly. Between > > switching back and forth from the non-inverting to the inverting configuration > > several times, I am fairly certain that both configurations were wired up properly. > > Hmm... "several times" does make it sound like a so


Re: Why Adding a Voltage Amplifier after a Transimpedance Amplifier reduce BW? Book Claim by 0.64

Started by Phil Hobbs in sci.electronics.design5 years ago

On 05/14/2015 11:52 AM, Felipe Jimenez wrote: > On Thursday, May 14, 2015 at 4:08:04 AM UTC-7, Phil Hobbs wrote: > > > Oh and I'm fairly...

On 05/14/2015 11:52 AM, Felipe Jimenez wrote: > On Thursday, May 14, 2015 at 4:08:04 AM UTC-7, Phil Hobbs wrote: > > > Oh and I'm fairly certain the non-inverting amplifier is wired up > > > correctly. Between switching back and forth from the > > > non-inverting to the inverting configuration several times, I am > > > fairly certain that both configurations were wired up properly. > > > > Hmm... "se


noise in instrumentation amplifier

Started by val in sci.electronics.design4 years ago 24 replies

Hello all, I have a basic instrumentation amplifier made with three MAX 44245 op amps. My problem is that I have too much noise in the 50 to...

Hello all, I have a basic instrumentation amplifier made with three MAX 44245 op amps. My problem is that I have too much noise in the 50 to 100 kHz bandwidth and I don't know how to reduce it. Maybe I don't have enough phase margin around 100 kHz (the GBW product of the 44245 is 1 MHz and the gain of the first stage of the instr. amplifier is about 10). However, the data sheet says that t...


Highly Linear ADC Driver Amplifier - need suggestions

Started by Darol Klawetter in sci.electronics.design7 years ago 20 replies

I'm currently researching the amplifier options for the output stage of a R= F receiver I'm designing. This stage will have a single-ended output...

I'm currently researching the amplifier options for the output stage of a R= F receiver I'm designing. This stage will have a single-ended output and wi= ll drive an ADC that has a SFDR of 100 dB. Of course, I need a highly linea= r amplifier to prevent washing out my ADC performance, but I don't want to = use one with differential I/O, which is typically used to drive high-perfor= mance ADCs...


Re: Why Adding a Voltage Amplifier after a Transimpedance Amplifier reduce BW? Book Claim by 0.64

Started by Phil Hobbs in sci.electronics.design5 years ago

On 05/14/2015 11:50 AM, John Larkin wrote: > On Thu, 14 May 2015 04:07:59 -0700 (PDT), Phil Hobbs > wrote: > > > > Oh and I'm fairly...

On 05/14/2015 11:50 AM, John Larkin wrote: > On Thu, 14 May 2015 04:07:59 -0700 (PDT), Phil Hobbs > wrote: > > > > Oh and I'm fairly certain the non-inverting amplifier is wired up correctly. Between > > > switching back and forth from the non-inverting to the inverting configuration > > > several times, I am fairly certain that both configurations were wired up properly. > >


Differential Amplifier is an input stage of every op-amp

Started by Patrick Chung in sci.electronics.design6 years ago

Generally, if input stage of an operational amplifier is realized as BJT tr= ansistor differential amplifier, op-amp has smaller slew rate,...

Generally, if input stage of an operational amplifier is realized as BJT tr= ansistor differential amplifier, op-amp has smaller slew rate, smaller volt= age offset and better CMRR. If it's realized as JFET transistor based diffe= rential amplifier, voltage offset is higher, CMRR is smaller but slew rate = is better.=20 Read more: http://www.cirvirlab.com/index.php/tutorials/167-bjt-tran...


Amplification factor for common emitter amplifier

Started by amal banerjee in sci.electronics.design12 months ago 70 replies

Is it possible to calculate the amplification factor for an amplifier,, e.g., a common emitter amplifier. This is because the amplification...

Is it possible to calculate the amplification factor for an amplifier,, e.g., a common emitter amplifier. This is because the amplification depends very much on the biasing condition, and so without a SPICE simulation, it appears impossible to determine the amplification factor. Am I right/wrong.


Re: Why Adding a Voltage Amplifier after a Transimpedance Amplifier reduce BW? Book Claim by 0.64

Started by Phil Hobbs in sci.electronics.design5 years ago

On 05/14/2015 12:15 PM, George Herold wrote: > On Thursday, May 14, 2015 at 11:57:36 AM UTC-4, Phil Hobbs wrote: > > On 05/14/2015 11:50 AM,...

On 05/14/2015 12:15 PM, George Herold wrote: > On Thursday, May 14, 2015 at 11:57:36 AM UTC-4, Phil Hobbs wrote: > > On 05/14/2015 11:50 AM, John Larkin wrote: > > > On Thu, 14 May 2015 04:07:59 -0700 (PDT), Phil Hobbs > > > wrote: > > > > > > > > Oh and I'm fairly certain the non-inverting amplifier is > > > > > wired up correctly. Between switching back and forth from the > > > > > non