Need help with LTspice Quantizer

Started by Anonymous in sci.electronics.design6 years ago 3 replies

AOA,Hi and greetings :) I am relatively new to SPICE environment ( never used it except in a recent course LAB). Now, we are given a Final year...

AOA,Hi and greetings :) I am relatively new to SPICE environment ( never used it except in a recent course LAB). Now, we are given a Final year Project on making and simulating a model of Multi-bit sigma delta ADC. Things are going quite normal until i found this thread https://groups.google.com/forum/#!topic/sci.electronics.design/ng_o8f7UPWY It has a code for quantizer which is t


Sine Shaper Inverter

Started by Kevin Foster in sci.electronics.design5 years ago 14 replies

Here is a circuit I designed in LTspice. https://app.box.com/s/fvepcv560r48gxvh2k2acdgc50mn5sws It converts an 8Hz square wave into a sine,...

Here is a circuit I designed in LTspice. https://app.box.com/s/fvepcv560r48gxvh2k2acdgc50mn5sws It converts an 8Hz square wave into a sine, and produces two anti-phase waves that each drive a resistive load. It appears to work as intended, but, as a learning process for me, I was wondering if anyone here could please critique the design and suggest any improvements. Kevin Foster ...


Anyone have an MC34063 SPICE model lying around?

Started by Tim Wescott in sci.electronics.design10 years ago 4 replies

Title says it all. LTSpice preferred. While we're on the subject -- does anyone know what the error amplifier gain is in the MC34063, and...

Title says it all. LTSpice preferred. While we're on the subject -- does anyone know what the error amplifier gain is in the MC34063, and what ranges one can expect in real life? The data sheets all call it a "comparator", but reading between the lines it's a gain stage followed by a comparator to the oscillator (which is what it has to be, to work correctly). -- My liberal frien...


Homework (SMPS)

Started by George Herold in sci.electronics.design8 years ago 6 replies

Hi guys, So I signed up for this power electronics course that Klaus linked= to a week or so ago. (from coursera and CU). =20 I wanted to...

Hi guys, So I signed up for this power electronics course that Klaus linked= to a week or so ago. (from coursera and CU). =20 I wanted to check my homework so I made an LTspice file. =20 (I=92ve changed it a bit so as not to give HW answer.) =20 I=92ve got a question. If you look at the simulation there is this rather l= arge turn on transient. =20 Transient has a period of ~1.3 mS (~77...


NE555 seems to have changed in one of the LtSpice updates?

Started by Maynard A. Philbrook Jr. in sci.electronics.design8 years ago 2 replies

Today I dropped the NE555 on the form and noticed the OUTPUT was matching the Vcc? This isn't correct and I am sure this has not been this...

Today I dropped the NE555 on the form and noticed the OUTPUT was matching the Vcc? This isn't correct and I am sure this has not been this way in the past. Also, when I use a pull up R from another source to lift it higher, which also used to work, it simply current sinks it at the Vcc of the chip.. The output of the timer on when is suppose to be a emitter follower and thus al...


Input Amplifier

Started by rickman in sci.electronics.design6 years ago 43 replies

I got help from Joerg some time back with an amplifier for an antenna signal for WWVB at 60 kHz. I was looking at a version in LTspice and...

I got help from Joerg some time back with an amplifier for an antenna signal for WWVB at 60 kHz. I was looking at a version in LTspice and noticed the bypass cap on the source leg of the second stage was a lot smaller than the others doing a similar job. It was reducing the gain of the second stage a bit and I increased it from 3.3 nF to 33 nF. Oddly enough, it dropped the gain of the ...


phase noise of a current starved vco phase noise with LT spice

Started by Anonymous in sci.electronics.design8 years ago 2 replies

hello! i am working on DPLL,CSVCO is a part of this,i need help how to determine the phase noise of that VCO with LTSPICE

hello! i am working on DPLL,CSVCO is a part of this,i need help how to determine the phase noise of that VCO with LTSPICE


A stupid question about Sine Generator in Spice/LTSpice

Started by M Philbrook in sci.electronics.design5 years ago 25 replies

I find it annoying that I can't simply set the starting degree angle I want without it causing an offset, unless I do 0. Currently I...

I find it annoying that I can't simply set the starting degree angle I want without it causing an offset, unless I do 0. Currently I get around this using the delay parameter and the sine will start with the correct offset so that it crosses the axes properly. I was doing a 3 phase transformer simulation the otherday and needed to do Delta, WYE etc, connections. Using DC offse...


Inductor saturation during smps startup

Started by Sylvia Else in sci.electronics.design5 years ago 21 replies

I was looking at using an LT1170 in a Positive-to-Negative Buck-Boost Converter, as per page 14 of this data...

I was looking at using an LT1170 in a Positive-to-Negative Buck-Boost Converter, as per page 14 of this data sheet http://docs-asia.electrocomponents.com/webdocs/13ec/0900766b813ec9fd.pdf Thing is, when I put this into LTSpice (using Linear Techology's own model of their part), it shows that the current through the inductor rises to 10 amps, during start-up, settling to something more ...


Strange muting circuit

Started by Bitrex in sci.electronics.design10 years ago 16 replies

The other day I was remembering a Roland synthesizer of mine I repaired a while back, and a strange circuit that I never did figure out...

The other day I was remembering a Roland synthesizer of mine I repaired a while back, and a strange circuit that I never did figure out the function of. Today on a whim I wired up the circuit in LTSpice, and unfortunately I'm no closer to understanding how it functions. For those who don't want to fuss with the netlist, I have a screen cap of the circuit in question here: http://i227.pho...


Flyback. LTspice. Questions!

Started by Ev in sci.electronics.design4 years ago 15 replies

Hi group, apologies for jumping straight in with a question but I've been following this group for a while, learning a bit, and now I'm...

Hi group, apologies for jumping straight in with a question but I've been following this group for a while, learning a bit, and now I'm stuck! I'm trying to quickly come up with a wide input power supply, 60-280VDC. Two low power 12V outputs, one common with the -ve input and one with the +ve. I have thrown a circuit together on the bench with LTC3805-5, an off the shelf Wuerth


Output Swing of Negatively Powered Op Amp

Started by Steve Morris in sci.electronics.design4 years ago 8 replies

Please look at the LTspice screen shot linked below. https://app.box.com/s/atozh8k6rx6g9p6zjviwhm0omntfe8gv The top amp is outputting 0.3V...

Please look at the LTspice screen shot linked below. https://app.box.com/s/atozh8k6rx6g9p6zjviwhm0omntfe8gv The top amp is outputting 0.3V to 3V which seems acceptable. However,the bottom amp will not swing any closer than about 1.2V from ground, being the "positive" rail in this instance. What changes do I need to make to the circuit to shift this closer to 0V so I am not wasting ...


LTspice DFLOP model errata?

Started by Ricky C in sci.electronics.design2 years ago

The only question mark is to whether to call it errata to the model or errata to the documentation? In the LT group it has been pointed out to me...

The only question mark is to whether to call it errata to the model or errata to the documentation? In the LT group it has been pointed out to me that all the digital devices work the way the designer intended if not the way they documented. So errata to the documentation perhaps? I believe Joerg was dealing with issues of the set/reset input polarities not being well documente


LTspice subckt model for AD734

Started by JosephKK in sci.electronics.design11 years ago 19 replies

I picked up the macromodel from AD(TI) for this IC. I=20 am using the manual to try to figure out how to=20 incorporate the model in a...

I picked up the macromodel from AD(TI) for this IC. I=20 am using the manual to try to figure out how to=20 incorporate the model in a circuit idea, but i hit up=20 against errors. This one has me baffled though. =20 The error i am getting is: "Port(pin) count mismatch between the definition of 'ad734.cir' and = instance xu1. The instance has more connections than the definition." ...


Making a Full Wave Rectified Signal in Ltspice.

Started by D from BC in sci.electronics.design10 years ago 9 replies

afaik it's not possible to set the 'Independent V source' alone to create a full wave rectified signal. It would be tidy to know for...

afaik it's not possible to set the 'Independent V source' alone to create a full wave rectified signal. It would be tidy to know for sure. Last time I used 2 out of phase generators and 2 ideal diodes. Simpler? The purpose is to have a simple model of a bridge rectifier on the mains.


Nice "Shop To Win" Tool Bar surprised.

Started by Jamie in sci.electronics.design10 years ago 8 replies

Yes, I got surprised when I needed the 7z "Seven Zip" Tool to unzip some compressed files to WAV format.. At least I think it was that, or...

Yes, I got surprised when I needed the 7z "Seven Zip" Tool to unzip some compressed files to WAV format.. At least I think it was that, or it could of been LtSpice I down loaded to install on my new PC. either one, the dates were the same. After which I installed, some where along the line these 2 little programs start to run in my machine.. "Shop to Win" and "JunkBoxJunkie" or s...


New LTspice Model Posted

Started by Jim Thompson in sci.electronics.design6 years ago 3 replies

See AD790_JT.zip on the Device Models & Subcircuits Page of my website: Behavioral model based on the datasheet only. Comments most...

See AD790_JT.zip on the Device Models & Subcircuits Page of my website: Behavioral model based on the datasheet only. Comments most welcome. Please report any issues. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations |


What would you call it?

Started by Jim Thompson in sci.electronics.design5 years ago 7 replies

What would you call it? I've developed a simple-minded subcircuit for use with NOISE analyses in Spice/PSpice/LTspice such that... o It...

What would you call it? I've developed a simple-minded subcircuit for use with NOISE analyses in Spice/PSpice/LTspice such that... o It passes DC at whatever RDC you set o It jumps to gmin/2 at some corner you set, FCO o It's a flat impedance at gmin for the rest of the spectrum I need a name for this PART ;-) (I'll post the subcircuit as soon as I decide on a name.) ...


LTspice question

Started by Syd Rumpo in sci.electronics.design7 years ago 4 replies

Either simple or impossible, I think... I have a circuit with several identical sections. I use parameters for the component values, eg {Rg}...

Either simple or impossible, I think... I have a circuit with several identical sections. I use parameters for the component values, eg {Rg} etc and use .param Rg = 12k etc. This works fine, of course. But what I'd really like is for one of the sections to have the real component values and for the other sections to copy them. So, for example R106 is set to 12k but R206 and R306 e...


Relaxation oscillators and SPICE

Started by Piotr Wyderski in sci.electronics.design7 years ago 25 replies

I am unable to simulate the followingg PUT-based relaxation oscillator in the most recent LTspice (with BC547B and...

I am unable to simulate the followingg PUT-based relaxation oscillator in the most recent LTspice (with BC547B and BC557B): https://upload.wikimedia.org/wikipedia/commons/9/9f/PUT_LED_blinker.png Nothing wants to oscillate. Looking for a bug I have also tried the simplest possible neon lamp oscillator (with Vstrike=100V, Vhold=50V, R=220k, C=1u), but there are no scillations either: ...