CEM3340: Difference between revisions

Jump to navigation Jump to search
Content added Content deleted
VisualWikitext
No edit summary
 
(49 intermediate revisions by 2 users not shown)
Line 1: Line 1:
The '''CEM 3340''' is a self contained [[VCO]], produced by [[Curtis Electromusic Specialties]]. With both [[exponential]] and [[linear]] control inputs and up to four output waveforms: [[triangle]], [[sawtooth]], [[square]], and [[pulse]] with voltage controllable [[pulse width]]. It has full temperature compensation making it extremely stable. Also included is provision for [[oscillator sync|hard and soft synchronization]] of the [[frequency]], and an output for easy adjustment of [[VCO high frequency tracking|high frequency tracking]].<ref name="3340ds">[http://www.cem3374.com/datasheets.htm CEM3340 data sheet] at CEM3374.com</ref>
The '''CEM3340''' and '''CEM3345''' are a self contained [[VCO]], originally produced by [[OnChip Systems|Curtis Electromusic Specialties]]. With both [[exponential]] and [[linear]] control inputs and up to four output waveforms: [[triangle]], [[sawtooth]], [[square]], and [[pulse]] with voltage controllable [[pulse width]]. It has full temperature compensation making it extremely stable. Also included is provision for [[oscillator sync|hard and soft synchronization]] of the [[frequency]], and an output for easy adjustment of [[VCO high frequency tracking|high frequency tracking]].<ref name="dslong">[https://static.miraheze.org/sdiywikiwiki/1/1c/CEM3340-3345_long.pdf CEM3340/3345 data sheet]</ref>


== CEM3340/3345 differences ==
⚫
== Projects ==
* The square wave output on the CEM3345 (pin 7) requires a pull down resistor to any negative supply greater than -4 volts.
⚫
The [[Digisound 80-2]] and [[Digisound 80-3|80-3]] are well designed and versatile analogue VCO and VCLFO.<ref>[http://www.soundonsound.com/sos/jan00/articles/digisound80.htm Digisound 80, Modular Synthesizer (Retro)], SOS Jan 2000 by Paul Nagle</ref><ref>[http://www.digisound80.co.uk/digisound/modules/80-2.htm 80-2 Voltage Controlled Oscillator]</ref> To prevent the IC being put under too much stress if/when the outputs are shorted, all outputs should have a series 1K resistor. The triangle wave output is unbuffered and should never be used to drive an output directly, add a J201 FET follower to buffer it.<ref>[https://www.muffwiggler.com/forum/viewtopic.php?t=24134 Does the A SOL MC-202 modular kit work on the SH-101?], Muff Wiggler forum, Nov 2010</ref> A better sine output can be achieved by using instead the [[Thomas Henry]] [[VCO-1 waveshaper]].<ref>[http://www.birthofasynth.com/Thomas_Henry/Pages/VCO-1.html The VCO-1 Project]</ref><ref>[https://www.muffwiggler.com/forum/viewtopic.php?t=143298 VCO/LFO PCB for CEM3340 chips], Muff Wiggler forum, Aug 2015</ref>
* The frequency control is pin 15 on the CEM3340, pin 17 on the CEM3345.
* The precision multiplier output is pin 14 on the 3340, pin 16 on the 3345.
* The reference current input is pin 13 on the 3340, pin 15 on the 3345.
* The hi-frequency track is pin 7 on the 3340, pin 8 on the 3345.
* The threshold voltage pin is pin 9 on the 3340, pin 10 on the 3345.<ref name="dslong"/>

== Clones and equivalents ==
In 2016 after twenty or more years of diminishing availabilty, in response to [[Coolaudio International Ltd.|Coolaudio's]] [http://www.coolaudio.com/features-page.php?product=V3340D V3340] re-design of the part to the same specifications, OnChip Systems remanufactured the 3340.<ref>[https://www.facebook.com/curtischips/posts/1173548609342828 Curtis Electromusic Specialties], Facebook, 5 June 2016</ref><ref>[https://ask.audio/articles/curtis-family-speaks-out-against-behringer-synth-clone-plans-using-cem3340 Curtis Family Speaks Out Against Behringer Synth Clone Plans Using CEM3340] by Rounik Sethi, Ask.Audio, 21 Mar 2017</ref><ref>[https://web.archive.org/web/20190613235511/http://synth-diy.org/pipermail/synth-diy/2017-September/166135.html CEM3320/V3320], SDIY list, Sep 2017</ref>

=== Alfa parts ===
[[Alfa Rpar AS]] produces the AS3340 and AS3345. The 3340 is available in both 16 pin DIP and SOIC packages, the 3345 is available in 18 pin DIP and 24 pin QFN packages. Alfa recommend a 51K resistor on the pulse output instead of the 10K resistor that the CEM3340 uses. <ref>[https://electricdruid.net/product/as3340-vco/ AS3340 VCO], Electric Druid</ref><ref>[https://www.alfarzpp.lv/eng/sc/AS3340.pdf AS3340] data sheet</ref>

The AS3340-HYB is pin compatible with the CEM3340. It is a AS3345F with an additional PWM comparator in order to minimize frequency modulation by the PWM control circuit.<ref>[https://modwiggler.com/forum/viewtopic.php?t=217648 AS3340-HYB New VCO chip], Mod Wiggler Forum, May 2019</ref><ref>[https://www.alfarzpp.lv/eng/sc/AS3340-HYB.pdf AS3340-HYB] data sheet</ref>

⚫
== Usage ==
⚫
To prevent the IC being put under too much stress if/when the outputs are shorted, all outputs should have a series 1K resistor. The triangle wave output is unbuffered and should never be used to drive an output directly, add a J201 FET follower to buffer it.<ref>[https://www.modwiggler.com/forum/viewtopic.php?t=24134 Does the A SOL MC-202 modular kit work on the SH-101?], Mod Wiggler forum, Nov 2010</ref> A better sine output can be achieved by using instead the [[Thomas Henry]] [[VCO-1 waveshaper]].<ref>[http://www.birthofasynth.com/Thomas_Henry/Pages/VCO-1.html The VCO-1 Project]</ref><ref>[https://www.modwiggler.com/forum/viewtopic.php?t=143298 VCO/LFO PCB for CEM3340 chips], Mod Wiggler forum, Aug 2015</ref>


== References ==
== References ==
Line 8: Line 24:


== External links ==
== External links ==
* [http://www.alfarzpp.lv/eng/sc/AS3340%20tip%20VCO%20_%20PWM%20.pdf Tech note on improving PWM stability of the ALFA AS3340]
* [https://cabintechglobal.com/tune3340 Precision Tuning of the AS3340 VCO] by [[Rob Hordijk]], September 2018
* [http://electro-music.com/forum/topic-54623.html The VCO-555] by Thomas Henry an approximation of the CEM3340
* [http://electro-music.com/forum/topic-54623.html The VCO-555] by Thomas Henry an approximation of the CEM3340
* [http://www.sdiy.info/w/images/CEM3310_datasheet.pdf CEM 3340 data sheet]
* [https://static.miraheze.org/sdiywikiwiki/1/1c/CEM3340-3345_long.pdf CEM3340/3345 data sheet]
* [http://synth.stromeko.net/DIY.html#CEMpics Picture of de-encapsulated defect CEM 3340] at Stromeko Synth World
* [http://synth.stromeko.net/DIY.html#CEMpics Picture of de-encapsulated defect CEM3340] at Stromeko Synth World
* [http://jhaible.com/legacy/tonline_stuff/hj_modul.html Dual VCO (CEM3340-based, with thru-zero FM and various types of sync)] by Juergen Haible
* [http://jhaible.com/legacy/tonline_stuff/hj_modul.html Dual VCO (CEM3340-based, with [[Through-zero FM|thru-zero FM]] and various types of sync)] by Juergen Haible
* [http://nonlinearcircuits.blogspot.co.uk/2016/08/things-to-come-cem3340-vco.html?m=1 Things to come: CEM3340 VCO], nonlinearcircuits, 17 August 2016
* [http://nonlinearcircuits.blogspot.co.uk/2016/08/things-to-come-cem3340-vco.html?m=1 Things to come: CEM3340 VCO], nonlinearcircuits, 17 August 2016
* [http://electricdruid.net/cem3340-vco-voltage-controlled-oscillator-designs/ CEM3340 VCO (Voltage Controlled Oscillator) designs] by Tom Wiltshire, 27 August 2016
* [http://electricdruid.net/cem3340-vco-voltage-controlled-oscillator-designs/ CEM3340 VCO (Voltage Controlled Oscillator) designs] by Tom Wiltshire, 27 August 2016
* [http://www.muzines.co.uk/articles/ics-for-electro-music/2561 ICs for Electro-Music (Part 1)] by [[Charles Blakey]]
* [http://www.muzines.co.uk/articles/ics-for-electro-music/2561 ICs for Electro-Music (Part 1)] by [[Charles Blakey]]
* [http://secretlifeofsynthesizers.com/the-vco/ A look at the VCO's of some famous analog synthesizers.] by [[Chris Meyer]], The Secret Life of Synthesizers, 25 Oct 2016
* [http://secretlifeofsynthesizers.com/the-vco/ A look at the VCO's of some famous analog synthesizers.] by [[Chris Meyer]], The Secret Life of Synthesizers, 25 Oct 2016
* [http://www.alfarzpp.lv/eng/sc/Tuning%20the%20AS3340.pdf Tuning the AS3340] by Rob Hordijk, 2018
* [https://www.richholmes.xyz/topics/synth/howto/3340/ 3340 VCO notes], Rich Holmes
=== Projects ===
=== Projects ===
* [http://www.birthofasynth.com/Thomas_Henry/Pages/VCO_Maximus-Detail.html The VCO Maximus] by Thomas Henry
* ''[https://www.eddybergman.com/2020/01/synthesizer-build-part-18-really-good.html A really good AS3340 VCO design!!]'' by Eddy Bergman
* [http://www.digisound80.co.uk/digisound/modules/80-2.htm Digisound 80-2] VCO, 1980
⚫
* andrewF [https://www.muffwiggler.com/forum/viewtopic.php?t=169673 CEM3340 VCO], Muff Wiggler forum, Oct. 2016, for Eurorack
* [http://www.digisound80.co.uk/digisound/modules/80-3.htm Digisound 80-3] VCLFO, 1980
⚫
* Datasette [https://www.muffwiggler.com/forum/viewtopic.php?t=170929 OPECEM3340 – v3 (True Zero) on its way soon – Morph delayed], Muff Wiggler forum, Nov. 2016 and [https://github.com/xnotox?tab=repositories on Github], for Eurorack
* [https://drive.google.com/file/d/0Bx5_5krPS9HMcThRRHRObjRwMUk/view VCO Deluxe] by Thomas Henry, Polyphony, Nov/Dec 1981
⚫
* TimoRozendal [https://www.muffwiggler.com/forum/viewtopic.php?t=170054 &#x0005B;pcb+panel&#x0005D; CEM3340 VCO for eurorack (8hp)], Muff Wiggler forum, Oct. 2016
* [http://www.proaudiodesignforum.com/forum/php/viewtopic.php?f=12&t=811 Low-Frequency VCO Gives Exponential Response] by Thomas Henry, Electronics, January 13, 1983, pp. 168-169.
* [https://imgur.com/gallery/vySr5 Hyperflange + Chorus] by Craig Anderton, Modern Recording & Music, Jul/Sep 1983
* [https://web.archive.org/web/20190613221410/https://sdiy.info/wiki/File%3AThe_Reprint_Collection_by_Thomas_Henry_CC_BY_NC.pdf Build a Precision Controller Clock] by Thomas Henry, Electronotes, May/June 1984, Special Issue E, pp. 11-17.
⚫
* andrewF [https://www.modwiggler.com/forum/viewtopic.php?t=169673 CEM3340 VCO], Mod Wiggler forum, Oct. 2016, for Eurorack
⚫
* TimoRozendal [https://www.modwiggler.com/forum/viewtopic.php?t=170054 &#x0005B;pcb+panel&#x0005D; CEM3340 VCO for eurorack (8hp)], Mod Wiggler forum, Oct. 2016
⚫
* Datasette [https://www.modwiggler.com/forum/viewtopic.php?t=170929 OPECEM3340 – v3 (True Zero) on its way soon – Morph delayed], Mod Wiggler forum, Nov. 2016 and [https://github.com/xnotox?tab=repositories on Github], for Eurorack
* [http://www.birthofasynth.com/Thomas_Henry/Pages/VCO_Maximus-Detail.html The VCO Maximus] by Thomas Henry, 2017
* [https://www.kichink.com/buy/1675875/trilobite-audio/vco-cem3340-pcb VCO CEM3340 PCB], Trilobite.audio
* [https://www.modwiggler.com/forum/viewtopic.php?t=200701 Kassutronics VCO 3340] (eurorack)
* [https://www.modwiggler.com/forum/viewtopic.php?p=2773821 &#91;ORDER&#93; OCTOGINTA-II Digisound 80-2 eurorack version], Mod Wiggler forum, Feb 2018
* [https://www.modwiggler.com/forum/viewtopic.php?t=197467 Digisound in eurorack] and [https://www.modwiggler.com/forum/viewtopic.php?t=201029 &#091;ORDER&#093; Digisound eurorack], Mod Wiggler forum, Mar 2018
* [https://www.reddit.com/r/synthdiy/comments/cwq82m/cem3340_vco_schematics_and_pcb/ CEM3340 VCO Schematics and PCB!], Reddit/synthdiy, 28 Aug 2019
* [https://web.archive.org/web/20210826023345/https://duskwork.net/product/self-tuning-vco-kit-eurorack/ Dusk work Self-Tuning VCO]
* [https://www.electro-smith.com/electro-boards/3340-vco-submodule Electrosmith 3340 VCO submodule]. SMT parts mounted on 0.1"/2.54 mm adapter PCB.
* [https://github.com/xnotox/CEM3340 xnotox/CEM3340], GitHub - OpenCem 3340 rev. 3 and Thru Zero Sync Expander
* [https://github.com/brer-rabbit/zoxnoxious Zoxnoxious Analog Synthesizer]
* [https://www.richholmes.xyz/topics/synth/kosmodrome/modules/oscillators/herovco/ AO Hero VCO], [[Kosmo]] format


[[Category:CEM ICs]]
[[Category:CEM ICs]]
[[Category:VCO ICs]]

Latest revision as of 16:37, 9 April 2024

The CEM3340 and CEM3345 are a self contained VCO, originally produced by Curtis Electromusic Specialties. With both exponential and linear control inputs and up to four output waveforms: triangle, sawtooth, square, and pulse with voltage controllable pulse width. It has full temperature compensation making it extremely stable. Also included is provision for hard and soft synchronization of the frequency, and an output for easy adjustment of high frequency tracking.[1]

CEM3340/3345 differences

  • The square wave output on the CEM3345 (pin 7) requires a pull down resistor to any negative supply greater than -4 volts.
  • The frequency control is pin 15 on the CEM3340, pin 17 on the CEM3345.
  • The precision multiplier output is pin 14 on the 3340, pin 16 on the 3345.
  • The reference current input is pin 13 on the 3340, pin 15 on the 3345.
  • The hi-frequency track is pin 7 on the 3340, pin 8 on the 3345.
  • The threshold voltage pin is pin 9 on the 3340, pin 10 on the 3345.[1]

Clones and equivalents

In 2016 after twenty or more years of diminishing availabilty, in response to Coolaudio's V3340 re-design of the part to the same specifications, OnChip Systems remanufactured the 3340.[2][3][4]

Alfa parts

Alfa Rpar AS produces the AS3340 and AS3345. The 3340 is available in both 16 pin DIP and SOIC packages, the 3345 is available in 18 pin DIP and 24 pin QFN packages. Alfa recommend a 51K resistor on the pulse output instead of the 10K resistor that the CEM3340 uses. [5][6]

The AS3340-HYB is pin compatible with the CEM3340. It is a AS3345F with an additional PWM comparator in order to minimize frequency modulation by the PWM control circuit.[7][8]

Usage

To prevent the IC being put under too much stress if/when the outputs are shorted, all outputs should have a series 1K resistor. The triangle wave output is unbuffered and should never be used to drive an output directly, add a J201 FET follower to buffer it.[9] A better sine output can be achieved by using instead the Thomas Henry VCO-1 waveshaper.[10][11]

References

  1. ^ a b CEM3340/3345 data sheet
  2. ^ Curtis Electromusic Specialties, Facebook, 5 June 2016
  3. ^ Curtis Family Speaks Out Against Behringer Synth Clone Plans Using CEM3340 by Rounik Sethi, Ask.Audio, 21 Mar 2017
  4. ^ CEM3320/V3320, SDIY list, Sep 2017
  5. ^ AS3340 VCO, Electric Druid
  6. ^ AS3340 data sheet
  7. ^ AS3340-HYB New VCO chip, Mod Wiggler Forum, May 2019
  8. ^ AS3340-HYB data sheet
  9. ^ Does the A SOL MC-202 modular kit work on the SH-101?, Mod Wiggler forum, Nov 2010
  10. ^ The VCO-1 Project
  11. ^ VCO/LFO PCB for CEM3340 chips, Mod Wiggler forum, Aug 2015

External links

Projects

Retrieved from "https://sdiy.info/wiki/CEM3340?oldid=21979"