Selector guide: Signal chain 3rd edition
Whether you need to meet tight accuracy requirements, reduce form factor size, or lower power consumption, this selector guide will help you choose the right signal chain components to optimize your design. Included are analog multiplexers and switches, ADCs, DACs, operational amplifiers, digital potentiometers, filters, voltage references, resistor-dividers, and integrated subsystems.
Thanks rsdio!
This is super interesting, only, I don’t see how they are achieving 0R03 on the Ron. Basically I’d like to know what type of switch it is inside – a semi conductor or a MEMS but I was unable to find info in the pdf
The document is a selection guide, with more details found in the typical data sheets. Looking at the MAX14752 data sheet for the full info, you will learn that Ron is actually 60Ω, but they are bragging that the flatness is 0.03Ω … in other words, the 8 channels are very closely matched to each other, but the Ron is not really so unbelievably small.
One reason I already had this data sheet on my hard drive is that this mux can handle a 72V supply! That’s also compatible with a ±36V bipolar supply. I’ve seen some high-end products use less-capable 8-channel analog mux chips and then get into CMOS lockup because the connected signals exceeded the chip’s supply limits. Even higher-end products use the MAX14752 or DG411 (±22V).
Ah I missed that part. So it is semi then… I understood, wrongly, that Ron is R03 and that’s why I started thinking MEMS :D …
It’s still a very good device :)
I can’t see why you misunderstood – they really brag about that 0.03Ω flatness. However, I guess they should brag, because the 60Ω Ron has an equivalent tolerance of 0.05% (yes, that’s 0.03/60=0.0005).
I CAN see (not can’t; wish I could edit)
:D
Anyhow I really don’t get why the hack noone makes MEMS switchers :D they could go into miliohm Ron range and would be as flat as one can imagine :D … I’m sure those would be loved by the audio industry :D
I’d never heard of MEMS before, so thanks for mentioning this technology. However, after reading about it, I suspect that such tiny physical switches could not carry enough current to keep the audiophiles happy. Tubes require hundreds of volts, FETs operate on tens of volts, and I have a hunch that MEMS would only handle microvolts or millivolts. A good audio mixer has ±20V rails or more, so the possibility for MEMS switching or selection seems slight.
If you have spec sheet links for MEMS parts, I’d be curious…
most of accelerometers, gyroscopes and similar chips are MEMS :)
as for audo and mems switch, I’m more thinking about preamp phase then about amplified signal. When you start pushing amps then reed relays get the job done :) without a problem :D