DG/Vishay-switcher

I always wonder what switch does what, so here it is:

Vishay also have switches with the DG3xx prefix (and others)

8p:

DG417: SPST normally closed

DG418: SPST normally open

Dg419: SPDT 

16p:

DG401: 2 x SPST in DIL16

DG403: 2 x SPDT

Dg405: 2 x linked SPST

Dg408: 1:8 mux

DG409: 2 x Linked 1:4 mux

DG411: 4 switches, normally closed

DG412: 4 switches, normally open

DG413: 4 switches, 2 pos and 2 neg logic, May be used as SPDT/DPDT

NB: Max +/-8V men kan funke med single supply opp til 16v:

Dg4051: 1:8 mux

Dg4052: 2 x linked 1:4 mux

Dg4053: 3 x spdt 

28p wide

Dg406: 1:16 mux

Dg407: 2 x Linked 1:8 mux

Dg445 - quad spst - what’s The catch?

Per the 12th of April 2022 I have:

2 x DG403 (dual SPDT)

2 x DG408 (1:8)

1 x DG409 (2 x 1:4)

5 x DG412 (4 x SPST)

1 x DG418 (SPST normally open)

8 x DG419 (SPDT)

Update

I ordered 306 Harris DG413 from Digikey as they were the cheapest I could find (around NOK 8.5). I also ordered 45 DG408 from Farnell, not as cheap, and will order 100 Intersil DG412 from Rs components (around NOK 8.5 too).

Analog switches and V logic

A quick note on the DG series analog switches:

I've successfully run at least one of these with a V_l (logic level voltage) of 15V while controlling the chip from a 5V MCU.

As I considered doing this for all switches (but with 3.3v logic level), I did a quick search that turned up these three posts:

"How do I connect the DG403 logic supply (VL) pin?"

https://en-support.renesas.com/knowledgeBase/4966520

"switches - VL input on analog switch"

https://electronics.stackexchange.com/questions/416272/vl-input-on-analog-switch

"Analog Switch switching voltage (DG412)"

https://modwiggler.com/forum/viewtopic.php?t=231474

They don't give the exact same answer though. The Renesas one says to use a 5V supply (even for 3.3v logic), derived from the 15V using a resistor voltage divider with high value resistors.

Now, they may not be talking about the same chip as the DG series are produced by a variety of suppliers, but at least it sort of validates just using a voltage divider.

The stack exchange post starts talking about excessive current draw. 

The modwiggler post suggests using zener diodes or a resistor divider connected to an emitter follower. 

For now, I'll stick with V_l = 5V but I'll test doing it with a resistor divider.

Digital 12/24dB switching for the moog filter

I built a digitally controllable switching circuit for the moog filter. I doubled up the differential buffer and connected one after the second pole and one after the fourth, giving 12dB and 24dB respectively.

After connecting a Vishay DG403 as a dual SPDT, I realised that the two outputs did not have the same DC offset anymore, so I had to move the balance trimmer to before the switch and duplicate it as well.

Resonance feedback is tapped after the 24dB buffer but before the switch, so resonance is always based on 24dB.

The circuit looks like this: