Lm13700 vco com/lit/ds/symlink/lm13700. TRAN 100u You also need to use the Alternate solver. State Variable Oscillator Project Type: Free Complexity: Intermediate Components number: 51-100 SPICE software: LTspice Software version: April 2015 Full software version nedeed : No Screenshots simulation images: The LM13700 is one of those chips that has been knocking around for years, minding its own business, despite the fact that it is a mind-bogglingly useful and versatile piece of silicon. Previous topic - Next topic The AS3340 is a precision voltage-controlled oscillator (VCO) IC, designed for use in high-quality analog synthesizers. inc, or . The results for both sim and proto are exactly the same - too much offset. Oct 12, 2018 · The LM13700 chips used both in this VCO and many of my own designs accept an absolute maximum control current of 2mA, and I usually aim for something like 100µA of reference current. The LM13700 is actually a dual OTA, as indicated by the pin connection diagram in Figure 1. and set:. gif Other Parts Discussed in Thread: LM13700 按照LM13700手册上搭建VCA电路，电压控制增益放大电路，其中输入信号幅值1Vp，频率10KHz，输入 LM13700 VCO Question. Granted, it can be a bit of a pain to work with, but it's still useful nonetheless. accidentally hitting the pin with a ground Sep 6, 2022 · And this is how the LM13700 itself is powered: LM13700 power inputs and decoupling capacitors Two decoupling capacitors (C1 and C2) are located close to the two power input pins. sub has lines that are not recognized by LTspice, so if you used that file as it is (e. May 23, 2015 · It is a variable-gain transconductance amplifier. Part Number: LM13700 Can i run the application examples from the datasheet, that states +-15v on +-12v? I am especially interested in the VCO, VCF and VCAs. This popped-up in another thread about a week ago, and shows the current-sink version, with the PNP and NPN swapping functions - the 'output' is the current from 'A' sunk through the transistor (the bit at the bottom): The LM13700 series consists of two current-controlled transconductance amplifiers, each with differential inputs and a push-pull output. 1 3 mV Oct 15, 2013 · Since the VCO is 1V/Oct (83mV per semitone) I don't want more then 5mV offset or the fundamental pitch of the VCO will change several cents or even semitones depending on the modulation amount! I have tested some circuits based on the LM13700 both in LTSPice and in the lab. I'm not sure what the reasons for that decision were. Jan 29, 2012 · I've never tried the VCO but I imagine C1 will need to be a fair bit bigger for lfo type speeds, Finally, for guitar circuits I feel that low noise is better than low distortion (the LM13700 distortion isn't particularly intrusive imo) so my personal perference is to not bother with the diodes and to scale the resistor dividers at the amp Mar 16, 2013 · Yep, ask for an LED blinker to test an LM13700, and you get LED blinker suggestions and LM13700 test suggestions, but not an LM13700-based LED blinker. Aug 1, 2018 · As a proof of concept I developed a VCO, which is now in a state "ready to publish". I'm not getting any oscillation, as I've read elsewhere people been having problems simulating the LM13700, especially in a VCO design. Extra Quick links. Aug 6, 2014 · I could use a basic LM13700 OTA-based VCA which requires offset trimming and more parts or I could try the quad 2164. You should be able to modify this for the saw vco. TI E2E support forums Oct 12, 2018 · The LM13700 chips used both in this VCO and many of my own designs accept an absolute maximum control current of 2mA, and I usually aim for something like 100µA of reference current. g. All Messages By This Member #141281 On 02/11/2022 11:55, jerzy przezdziecki via groups. It produces square and triangle wave, can be controlled with voltage (LFO, sequencer, etc) and easy to build. Figure 33. LM13700 VCO Stability. 1 hz to 50 hz? - Output 0 to +5v. This final sample is one that I recorded shortly after breadboarding the VCO-1. The inputs include linearizing diodes to reduce distortion, and the output current is controlled by a Dec 16, 2012 · I found another LM13700 model that's supposedly more accurate and was able to get the triangle/square vco simulation working. A few months ago I bought my first LM13700 and started playing with it. View LM13700 by Texas Instruments datasheet for technical specifications, This VCO operates from 5 Hz to 50 kHz with less than 1% THD. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next LM13700 VCO Question. I also added:. Apr 14, 2017 · Thomas Henry knows how to build a proper VCO with 13700 (the famous VCO-1). From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next If for whatever reason you want to go all-discrete instead of using a VCO IC. Eight VCO cores sharing a common control system. \$\begingroup\$ Isn't it all about making sure the VCO has a 1 volt (for example) per decade frequency sweep capability. Nov 29, 2016 · [Solved] Troubles breadboarding TH VCO-1 with LM13700 Post by atoav » Tue Nov 29, 2016 12:25 pm This semester we're doing a synthesizer DIY workshop at our university and we thought of building Tom Whitwell's Eurorack adaption of the classic Thomas Henry VCO-1. com SNOSBW2E – NOVEMBER 1999– REVISED MARCH 2013 LM13700 Dual Operational Transconductance Amplifiers with Linearizing Diodes and Buffers Check for Samples: LM13700 1FEATURES DESCRIPTION The LM13700 series consists of two current 2• gm Adjustable over 6 Decades controlled transconductance amplifiers, each with A +/-5-volt version of an LM13700 OTA VCO. 3340 vco (4hp) adsr envelope generator (4hp) buffered multiple (3hp) cycling envelope generator (4hp) digilfo (6hp, vclfo) dual vca (3hp, uses a lm13700 ota) looping attack/release envelope generator (6hp) noise lab (3hp) offset/gain utility (4hp) passive low pass gate (2hp) power supply unit/module (6hp) sub modulator (6hp, advanced sub Dec 11, 2014 · It uses 1 ota stage, there are 2 VCOs on the PCB. Nov 16, 2022 · Hello, I would like to discuss my idea, that I could control a VCA (built from a LM13700 OTA) from a DAC, linear in dB (for example 1V per 20dB attenuation). 1 LM13700 filter with a Low pass or High pass switch with CV for cutoff; VCO clone, originally made by HAGIWO (link in japanese) RP2040 chord VCO clone in SMD. Has anyone any ideas? I've just successfully built a VCO. Would appreciate any input. Dec 18, 2020 · Thomas Henry VCO 555 stripboard layout DIY module instructions eurorack There's only two TL074's, an LM13700 and a TLC555. options noopiter gminsteps=0 srcsteps=0" helps a lot. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next Jun 25, 2012 · then to get to an exponential VCO, you might use your LM137000 as a "Logarithmic Current Source", you might get this to sort of work. Check out our DIY 3340 module. 5kHz range. com SNOSBW2D – MAY 2004– REVISED SEPTEMBER 2004 Electrical Characteristics (1) LM13700 Parameter Conditions Units Min Typ Max Input Offset Voltage (VOS) Over Specified Temperature Range 0. I googled "triangle VCO with LM13700" and found Thomas Henry's excellent "555-VCO" on Muffwiggler. Jan 9, 2016 · I am trying to work through the math of the following schematic pulled from the LM13700 datasheet: I can certainly hook this up and mess with the values to change the frequency range to my liking (and I will) but I am more interested in working out the math formula using the values provided in the data sheet at this point. Nov 2, 2022 · I don't know what you did to fix the circuit, but I edited the LM13700 symbol so it matched the datasheet. The result exceeded my wildest expectations - a perfectly usable dual-core VCO with a Other Parts Discussed in Thread: LM13700. Here are my design requirements - Frequency controlled by 0 to +5 CV - LFO frequency range, something like 0. Jan 28, 2014 · I've been messing around with a LM13700 on the TINA simulator. simple_vco. On the cellF action panel, 1 LM13700 is used for a VCO and a VCA, so same idea The schematic is on pg3 of the build guide As shown in the schematic, you get approx 18Hz up to 9. Very versatile, but you need to think "outside the box" to use it effectively. May 8, 2015 · I'm still unable to get the triangle/square VCO circuit from the LM13700 datasheet simulating correctly under MultiSIM. My LM13700 is a SMD version and covered with foam tape (incl. I'm actually surprised to see the reference current chosen so low as 10µA in the 555 VCO. I've already built a VCO around the 3340 chip, and I set out to design one on my own. The IC is an LM13700 OTA (operational transconductance amplifier). Aug 5, 2013 · Breadboarding my first lm13700 vco, straight out of the datasheet, with thomas henry's exponential converter. io> On Behalf Of jerzy przezdziecki via groups. Linearizing LM13700 VCO jerzy przezdziecki. i want to use a single LM13700 instead of two CA3080, but i am a little unsure about what to do with the pins of the LM13700 that the CA3080 does not have: buffer input, buffer output, diode bias. This VCO has a wide tuning range (adjustable range of over 750 kHz) with a maximum frequency of around 20 MHz depending on components selected. A voltage controlled oscillator is an oscillator whose frequency is controlled by an input voltage. Board Rules; Bookmarks; Merchandise; New Posts (Non-Market) LM13700 VCO Question. 5 5 mV Input Offset Change 5 μA ≤IABC ≤500 μA 0. I found that a nice way to use this amplifier is to overdrive it with the triangle wave. 3. I’m using the triangle/square circuit found on page 19, and I can’t get it to oscillate at all. Dec 10, 2006 · Bonjour à tous, je cherche à réaliser un montage à base d'un LM13700 il s'agit d'un VCO proposé d'ailleurs par la datasheet du LM. he LM13700 data-sheet includes a plan for a sine wave VCO. The other half of the LM13700 has been carefully crafted into a release envelope generator with super snappy exponential curves, which has a FAST/SLOW May 15, 2022 · \$\begingroup\$ @user1505399 What Ste is saying is that the contents of the lm13700. 25 per VCA with minimal support circuitry. The VCO is at page 10. May 27, 2019 · Hi everyone, I’m working on a vco that I built using a schematic from page the Texas Instruments datasheet for the lm13700. As far as I know, most VCA modules uses either CEM3360 or SSM2164 or LM13700 chip, or there is also a less popular one THAT2180, with SSM2164 being the most popular choice e. They have independent outputs but they're meant to be used as a single unit, for chorus and cloud effects, with adjustable detuning and some extra features, including an adjustable-coefficient temperature compensation system. The LM13700 is a two channel current controlled differential input transconductance amplifier with additional output buffers. Two versions: A Diode Limited Leveller. Oct 29, 2021 · LM13700 OTA Offset removal: Analog & Mixed-Signal Design: 9: May 18, 2023: M: lm13700 as a voltage controlled current source: Homework Help: 18: Nov 13, 2022: LM13700 as VCR wrong values: PCB Layout , EDA & Simulations: 15: Jan 22, 2022: LM13700 VCO Design help: Analog & Mixed-Signal Design: 3: Jul 15, 2016: M: help in amplitude modulator ic nizable to those familiar with OTA-C LPFs found in many synthesizers using ICs such as the CA3080, LM13700, BA662, IR3109 and SSM2040. marcelds Common Wiggler Posts: 131 i am working on a double thomas henry vco-1. In the VCO above, the 3280 is used as the current source for the cores just like in a triangle core VCO. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 10 posts • Page 1 of 1. PCB, Top side. 28 posts 1; 2 LM13700 VCO Question. If not, you will have to change components. Linearizing diodes are provided at the inputs to reduce distortion and allow higher input levels. options cshuntintern=1e-13 + gmin=1e-9. You can either use a potentiometer to supply a variable voltage between 0V and 5V or you could use the output of an oscillator or a 1V octave keyboard if you have one. As this circuit only uses one half of the LM13700, the other is free to be used for something else. You can also use the ICM7555 (which is From: LTspice@groups. com simulation Post by guest » Mon Jun 17, 2024 11:08 pm it was miscalculating the capacitor voltage, dropping it down on transitions appropriately, but then reversing the diode voltage and not adding that back in to the capacitor voltage for some reason. To test the VCO, you will need to provide input voltages to the summing stage U1B. io wrote: Yes, you are right and I didi it already. If at all one could consider the related state variable oscillator with transconductance amplifier (e. The setup for this sample is quite simple: The PWM output of the VCO-1 is sent through my breadboarded Thomas Henry Mankato filter, through reverb and then into my Korg D8 recorder. Oct 15, 2013 · Since the VCO is 1V/Oct (83mV per semitone) I don't want more then 5mV offset or the fundamental pitch of the VCO will change several cents or even semitones depending on the modulation amount! I have tested some circuits based on the LM13700 both in LTSPice and in the lab. LM13700 VCO jerzy przezdziecki. It's a tri core VCO with a useful range >8 octaves. Darlington buffer U1D is unused. Aug 8, 2016 · Testing the VCO. Jul 15, 2016 · I'm designing a VCO using TI's LM13700 (Datasheet below) http://www. LM13700/LM13700A Dual Operational Transconductance Amplifiers with Linearizing Diodes and Buffers May 1998 LM13700/LM13700A Dual Operational Transconductance Amplifiers with Linearizing Diodes and Buffers General Description The LM13700 series consists of two current controlled transconductance amplifiers, each with differential inputs and a push-pull output. The two amplifiers share common supplies but otherwise operate independently. pdf On page 19 there is a pretty good looking schematic. com SNOSBW2F –NOVEMBER 1999–REVISED NOVEMBER 2015 6. Basically, the voltage input into the VCO chip controls how many times a digital signal will oscillate in a given time period. The specification sheet of the LM13700 that describes this VCO circuit gives the oscillation frequency as 4 I R C 12 3 I f A C osc = . am i supposed to connect them to ground of should i leave them floating? LM13700 VCO Stability. All Messages By This Member #141272 Hello, I’m trying to recreate the triangle / square VCO from its datasheet - Figure 33. The LM13700 is at the heart of many VCFs, VCAs, VCO wave shapers, Get Make: Analog Synthesizers now with the O’Reilly learning platform. Clean sine wave is priority, and I've read that the Sinusoidal VCO (figure 38 on TI's datasheet) should produce a very clean sine output. 电子发烧友网为你提供ti(ti)lm13700相关产品参数、数据手册，更有lm13700的引脚图、接线图、封装手册、中文资料、英文资料，lm13700真值表，lm13700管脚等资料，希望可以帮助到广大的电子工程师们。 Feb 4, 2021 · Although I'm building all the modules myself, I decided to adhere to the Doepfer Eurorack standard. I'm using my Thomas Henry keyboard to control the VCO and filter frequencies. The core oscillator is half of an LM13700, a buffer amp for the triangle, and a 555 timer. I'm thinking the VCO in fig 33 might work nicely. These two drops are part of a current mirror that feeds into the long-tail pair of the LM13700s inputs. It is a modern reissue of the classic CEM3340 VCO, known for its stability, accuracy, and versatility in generating audio waveforms. I even managed to add a little extra of my own design: normally this is a bi-polar LFO meaning all the outputs go from -5 to +5 volt but I added a uni-polar feature with two extra outputs for the saw-triangle-ramp wave and the sinewave that go from 0 to +10 volt. The discreet sawtooth VCO I’m building is too complex for breadboarding and does not deliver a decent sawtooth (probably due to distortion picked up somewhere in the breadboard). From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! Moderators: Kent, Joe. If you're going to lay out a new PCB to do this, I think you could use the LM13700. It's a bog standard spec I'm trying to simulate, which I couldn't get going in LTSpice first off, so I tried TINA TI, but still to no avail. The heart of the module is a VCO which is built around one half of a LM13700. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next Aug 1, 2018 · As a proof of concept I developed a VCO, which is now in a state "ready to publish". 2) Stop messing around with 13700. The audio signal levels are pretty standard, but Eurorack envelope modules vary in the output level they provide. If you increase the 33k resistor to 39k, it will range from approx 15Hz up to 11. marcelds Common Wiggler Posts: 131 From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! LM13700 VCO Stability. Needless to say, I'd like to be able to change the frequency of this VCO. I have trawled through the net to no avail. Sep 10, 2017 · This is based on the EFM 4614 VCO, just left out the triangle wave out put, so it should work. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next It might be a good idea to first try the conversion on the simpler single amplifier VCO in the LM13700 datasheet. For the component values given, amplifier gain is de-rived forFigure 2as being: VO VIN e 940 c IABC LM13700 VCO Question. Here's the schematic I'm inputting into MultiSIM, I've checked it a pile of times but maybe there's something I'm missing: But when I run the simulation the only output I get on the scope is this: The VCO-1 design is a simple, yet highly musical VCO and the VCA-1 design is another uncomplicated, yet highly effective VCA that fits right in with the VCA-1. LM13700 Dual Operational Transconductance Amplifiers with Linearizing Diodes and Buffers General Description The LM13700 series consists of two current controlled transconductance amplifiers, each with differential inputs and a push-pull output. 28 posts 1; 2 LM13700 VCO Stability. Dec 29, 2019 · It uses a TL084 quad opamp chip and a LM13700 OTA chip. Darlington buffer U1D (pins #9 and #10) is unused in this circuit. Hello Engineers, I'm hoping some one can help me sort out a plan for using the LM13700 as an LFO. However, when it's connected to a voltage source (potentiometer) it doesn't change the frequency but the amplitude. Ramp, Pulse/Square, and Triangle outputs LM13700 - Anyone familiar with prototyping VCOs using this chip please? Started by frequencycentral, June 27, 2008, 01:59:56 PM. I believe an LM13700 would work fine for this, though the performance might be slightly lower than the 3280. Aug 15, 2013 · The LM13700 OTA chip has an interesting schematic for a triangle VCO in its datasheet. Working the math is no issues, but all the formulas are using Ic and Ia, and to get these I need to know the voltage at the two points I've marked below. Tim Stinchcombe wrote:It is a very standard set-up, though generally only used when accuracy isn't a concern. Thomas Henry used it in his Bass++ project. 2V) above the -12V rail. Let’s assume we want +/-5V (10V pp) input and output signals, and let’s design for a 0→5V control voltage (gain CV) level. It's a standard setup for the LM13700 from the data sheet (Square/Triangle VCO) and I have some initial conditions which can be seen in LTSpice, to help kick it into oscillation (it LM13700 Dual Operational Transconductance Amplifiers with Linearizing Diodes and Buffers General Description The LM13700 series consists of two current controlled transconductance amplifiers, each with differential inputs and a push-pull output. In this circuit, we will show how we can build a voltage controlled oscillator (VCO) with a 555 timer chip. it might not tune (be true to a perfect some volts per octave curve) well enough. O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers. 4 Electrical Characteristics These specifications apply for VS = ±15 V, TA = 25°C, amplifier bias current (IABC) = 500 μA, pins 2 and 15 open unless Jul 8, 2017 · These operate over 5 or more decades of current, and I only need 3-4. Note that if this is to be part of a synthesizer project you'll need octave / volt tuning and not linear tuning as per your design and TI/Nat semi design. Once you wrap your head arround what it does, and look at the datasheet examples, you realize that you can make literally everything you could imagine out of it. Jun 15, 2015 · I googled "LM13700 VCO" and the top answer was the pdf file which contained: - Figure 37 should help and figure 38 is for a sinewave. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! Moderators: Kent, luketeaford, Joe. Even though the schematics implies +-15V (30V) I only used 0-9V. 5 it mentions "The VC Lo-Pass Filter of Figure 29 may be used to produce a high-quality sinusoidal VCO. Mar 9, 2020 · AeroSigma wrote: ↑ Mon Mar 09, 2020 4:30 am I'm wanting to make a simple VCO and was looking to find the Thomas Henry VCO in euro rack format. , luketeaford. Linearizing Sep 29, 2021 · This seems to be a simple yet complicated question. 3 dB. MSK 004 "Octothorpe" Octuple VCO. Now it oscillates correctly and simulates at a reasonable speed. Looking through the LM13700 datasheet I noticed under section 8. May 8, 2017 · Hi guys, I'm having an issue simulating the LM13700 in LTSpice. Apr 14, 2017 · Hi all, I'm trying to get a VCO circuit using an LM13700 up and running. 28 posts 1; 2 LM13700 - Anyone familiar with prototyping VCOs using this chip please? Started by frequencycentral, June 27, 2008, 01:59:56 PM. They were thinking about second-sourcing the CA3080, and the new 16-pin package made a dual CA3080 an easy exercise (just flip the layout to do the other side). marcelds Common Wiggler Posts: 131 LM13700 VCO Stability. To explain in more detail: The signal chain is supposed to be DAC -> Exponential converter with current output -> OTA bias current I ABC. The "triangular-square wave VCO" from the data sheet should work. " though I can find no reference as to how to modify the circuit to self oscillate as there's no resonance input. The long term idea is to built a Ring Modulator around an AD633, and I wanted to use an LM13700 for oscillator duties. Check out this article. Pour simuler le montage, j'ai utilisé LTSpice, mais impossible d'avoir quelque chose de probant ! j'obtiens un signal continu et ce quelque soit les sorties (deux étage, l'un permettant d'avoir un VCO signal PWM et l'autre dent de scie dû à l'intégrateur). I found this adaptation complete with layout and panel design from this post here on muff wiggler. This is just what I had in mind. 28 posts 1; 2 vco/ cd40106. for log amps, i had always considered building one out of Analog Devices parts and for a VCO, you should look up circuits for that. The VCO has a HIGH/LOW switch as well as a SWEEP control, which defines it’s response to the onboard envelope. LM13700). Jun 6, 2023 · A Voltage Controlled Oscillator (VCO) produces a waveform with a frequency that can be tuned by adjusting a control voltage. From circuitbending to homebrew stompboxes & synths, keep the DIY spirit alive! 28 posts 1; 2; Next Jun 20, 2021 · LM13700 VCO Question. Modifying the cap in the integrator path of the OTA from 220pF to 2. Assembly guide Feb 23, 2014 · The LM13600 and LM13700 started out life as a practice piece for a new mask designer. it may be one of those situations where you have three attributes—good v/oct tracking, super simple design, and all-analog discrete components—and you can choose two. 4 4 mV IABC = 5 μA 0. pins). 5kHz Jun 11, 2023 · A wien bridge is relatively easy with a fixed frequency, but difficult to build as a VCO. They seem to be roughly $5 each in low quantities, working out to $1. In almost every situation, 2164 is a better choice (as long as you terminate it to virtual ground). vco/ cd40106 MS-20 clones built around the LM13700 chip; two LM13700 amplifiers to provide a Stereo Volume Control with a typical channel-to-channel gain tracking of 0. Differences are the lack of a voltage divider as the input is a ground-referenced current instead of a mV-range voltage, and inverting op-amp Dec 2, 2024 · Re: Hard Sync LM13700 triangle square phase shifter VCO Post by AElliott » Mon Dec 02, 2024 7:52 pm Wow just tried this, a few total failures then it started to show signs of improvement. A Eurorack VCA with the LM13700. Oct 1, 2023 · Re: Simple VCO from LM13700 Datasheet not working in falstad. When switching from very low to very high frequencies I could hear a small thermal "tune in" effect on the VCO frequeny which must come from the self heating of the current mirror which is immediately regulated away. The non-linear characteristic of the LM13700 results in something very close to a sine wave. This 1 volt delivers (say) 100 Hz, 2 volts delivers 200 Hz, 3 volts delivers 400 Hz, 4 volts delivers 800 Hz. . LM13700 VCO Tony Casey. 2nF gives a frequency range from LFO (too slow to measure on my scope, maybe ~1Hz though) to 18kHz. This is a Voltage-Controlled-Oscillator (VCO) circuit that can be easily made using common discrete components that outputs extremely linear triangle waves in addition to square waves at fairly high frequencies (up to around 7 MHz depending on the components selected) with a wide tuning range LM13700 is the single best chip for diy synth building. They had a few pins left over, so they added the Darlington buffers and the predistortion diodes. Here is the Falstad Circuit Simulator Link to the circuit in case you want to mess around with it!. io <LTspice@groups. Each of its OTAs is an improved version of the CA3080, and incorporates input linearizing diodes that greatly reduce signal distor- Jun 15, 2015 · I've successfully built this VCO circuit using an LM13700 that works just fine if the VC (the 510K resistor) is not connected to anything. It has tri,saw,square and sine wave outputs, CV,hard sync and PWM inputs and, as a bonus, voltage controlled sine distortion. ti. LM13700 www. io Sent: Sunday, January 22, 2023 2:10 PM To: LTspice@groups. io Subject: EXTERNAL: Re: [LTspice] LM13700 VCO simulation endless processing Thanks a lot Andy, this ". Previous topic - Next topic LM13700 VCO Question. LM13700 VCO Question. I think a LM13700 VCA solution would probably work out to about the same but with more parts required. A Gain Multiplier Leveller. marcelds Common Wiggler Posts: 131 The applied voltage should be measured at TP8. Intellijel Quad VCA / MI - Veils. 10 posts • Page 1 of 1. Back in those days, as Thomas' summer of fun ended and he headed back into the depths of another semester of academia, he fired another of these designs over the bow of my ship; the improved second-generation OTA IC — the LM13700 — which does not suffer from these snags. Be sure your VCO oscillates at half of the reference frequency when the applied voltage is less than 5 V. Jun 25, 2014 · no, that circuit works very well, but is beyond my understanding of how he uses the lm13700 and 555 together so i wanted to experiment myself by just using the data sheet to start me off using a basic lm13700 vco and a simpler expo generator and make a simpler vco to learn a bit doing it myself rather than just copy a design, problem is i dont really know enough as you can tell lol, thanks for Aug 13, 2023 · The LM13700 bias voltage sits two diode drops (about 1. lib), errors should have come out -- you need to give us the exact errors, otherwise there's not enough information. 3 4 VOS Including Diodes Diode Bias Current (ID) = 500 μA 0. See the datasheet for a schematic of the internals and take care: directly connecting any low-impedance source, e. RP is provided to minimize the output offset voltage and may be replaced with two 510X resistors in AC-coupled applica-tions. with a simple . eolnyzdtxkkiujnbztbihpqbwdgqkcyzwcyoegxgzxohdrjc