A couple weeks ago, I started a thread with the same title over at DIYstompboxes: Plug-n-Play Buffered Electrical Bypass Using CD4053 and Momentary SPST.
I want to create a buffered electrical bypass scheme activated by a momentary SPST switch (similar conceptually to what is found in most Boss pedals). And rather than use discrete components like Boss does, I thought it might be simpler to use ICs. I want it to be "plug n play" in that it's generic enough to work with most typical effect PCBs (e.g. PedalPCB, EffectsLayouts, AionFX, etc). The other use-case is to be a relatively easy copy-paste circuit one could integrate into their own PCB design.
The basic idea is:
The buffer is standard fare, nothing interesting here.
I've been using this hex inverter switching control scheme for a year or so now with success (most of my recent builds use this, check build report history).
The CD4053 switching scheme is copied from RG Keen's article: Bypassing and Switching with the CD4053 CMOS Analog MUX.
My goals here are (1) transparent buffer, (2) no mechanical parts to wear out, (3) ultra-low power consumption, (4) low cost, (5) use modern, readily-available commodity parts. "No mechanical parts to wear out" doesn't include the momentary SPST (and that's only two wires, easily replaced).
Attached is the schematic, and a render of the prototype board I'm having fabbed (should be delivered this week). The physical size probably turns off a lot of people (myself included), but my plan is to miniaturize this with SMD and have a bunch pre-made.
If anyone is interested in these boards, I'm happy to send them out for free, as I would appreciate additional testing and validation!
I want to create a buffered electrical bypass scheme activated by a momentary SPST switch (similar conceptually to what is found in most Boss pedals). And rather than use discrete components like Boss does, I thought it might be simpler to use ICs. I want it to be "plug n play" in that it's generic enough to work with most typical effect PCBs (e.g. PedalPCB, EffectsLayouts, AionFX, etc). The other use-case is to be a relatively easy copy-paste circuit one could integrate into their own PCB design.
The basic idea is:
- TL072 signal buffer
- CD40106 CMOS inverter for footswitch control and status LED driver
- CD4053 for electrical analog signal switching
The buffer is standard fare, nothing interesting here.
I've been using this hex inverter switching control scheme for a year or so now with success (most of my recent builds use this, check build report history).
The CD4053 switching scheme is copied from RG Keen's article: Bypassing and Switching with the CD4053 CMOS Analog MUX.
My goals here are (1) transparent buffer, (2) no mechanical parts to wear out, (3) ultra-low power consumption, (4) low cost, (5) use modern, readily-available commodity parts. "No mechanical parts to wear out" doesn't include the momentary SPST (and that's only two wires, easily replaced).
Attached is the schematic, and a render of the prototype board I'm having fabbed (should be delivered this week). The physical size probably turns off a lot of people (myself included), but my plan is to miniaturize this with SMD and have a bunch pre-made.
If anyone is interested in these boards, I'm happy to send them out for free, as I would appreciate additional testing and validation!
