zamproject
Well-known member
- Joined
- May 11, 2010
- Messages
- 1,502
Hi all
I'm thinking about designing a 4 stereo digitally controlled GSSL switch board
My only concern for the moment is the analog switch/multiplexer
So far the only part that fit my requirement is the DG408/409
https://docs-emea.rs-online.com/webdocs/14f5/0900766b814f5ad4.pdf
...but the ON resistance is relatively high (about 40ohm for +/- 12 or 15V supply) especially for the lower attack setting,
more than 5% for the lowest (0.3), 2.5% for 1ms, after that it's ok (below 1% resistor)
As the ON resistance is not constant VS drain voltage would you consider this as an issue,
Would you just compensate basically to have Ron + Ratt equal to "original" value ?
Or just don't care for the 5% +/-1% (dynamic) mismatch ?
The switches logic will probably be drive by 595 SRIO and the 4 threshold and 4 gain by 8ch DAC (12 bit should be enough...)
The idea is to have all this in a 2U (with external psu) or 3 U rack, only one set of encoder/button/led with 4 unit select/link, and midi I/O for recall/dump/automation
Best
Zam
I'm thinking about designing a 4 stereo digitally controlled GSSL switch board
My only concern for the moment is the analog switch/multiplexer
So far the only part that fit my requirement is the DG408/409
https://docs-emea.rs-online.com/webdocs/14f5/0900766b814f5ad4.pdf
...but the ON resistance is relatively high (about 40ohm for +/- 12 or 15V supply) especially for the lower attack setting,
more than 5% for the lowest (0.3), 2.5% for 1ms, after that it's ok (below 1% resistor)
As the ON resistance is not constant VS drain voltage would you consider this as an issue,
Would you just compensate basically to have Ron + Ratt equal to "original" value ?
Or just don't care for the 5% +/-1% (dynamic) mismatch ?
The switches logic will probably be drive by 595 SRIO and the 4 threshold and 4 gain by 8ch DAC (12 bit should be enough...)
The idea is to have all this in a 2U (with external psu) or 3 U rack, only one set of encoder/button/led with 4 unit select/link, and midi I/O for recall/dump/automation
Best
Zam