THAT5173 Preamp Controller IC

[mediatechnology]

THAT has just announced the 5173 which has 0-60dB range in 3 dB steps.

http://www.thatcorp.com/datashts/THAT_5 ... asheet.pdf

It fixes the gain range to provide equal dB steps in the first 6 dB of range.

Glad they did this.

[promixe]

thatdipmini_v1.JPG (24.49 KiB) Viewed 14639 times

I call this THATDIP mini (as opposed to THATDIP full-featured 1570/5171 adapter I designed a while ago). It's 90% done. It is DIP-24 with 1570/5173 on-board and most essential pins routed out to make a great mic preamp in as tiny DIP package as possible. I will post more details once this is developed and integrated with my UMPC controllers (front panel, MIDI, and Ethernet).

Thanks!

PS: It's funny, the adapter is pretty much finished, but I have no clue where to get the 5173s to prototype it with. =))) Any idea when Mouser will start carrying them?

[mediatechnology]

I'll see what sample status is.

You might still want to consider splitting Rg...

[promixe]

Ok, I see your point about splitting Rg's.

Do you think splitting Vcc/Vee for the chips is necessary as was done on the 1570/5171 adapter? As far as the adapter's intended purpose do you think many people will run 1570 at ±18V and 5171 at ±17V to get that little extra input headroom?

The next form factor up is DIP-28, so we get 4 "extra" pins. Let's see here... =)

This is how I did it on the 1570/5171 (in blue are 5171 pins, in green are 1570 with original datasheet pin#'s in () ):

pinout_v3.gif (23.5 KiB) Viewed 14637 times

[mediatechnology]

As far as the adapter's intended purpose do you think many people will run 1570 at ±18V and 5171 at ±17V to get that little extra input headroom?

Not sure I know enough to answer that. Keeping it to 28 pins might be better than 32.

[JR.]

Unless there's a huge cost/size penalty between 32 and 28, I might be tempted to give the extra flexibility,

Is there any chance of subtle PSRR issues from common rail connection and common path on sub board?

JR

PS not to hijack but i am curious about IPAD, or mac/PC software to talk to digital controlled gadgets like this.

[promixe]

PS not to hijack but i am curious about IPAD, or mac/PC software to talk to digital controlled gadgets like this.

I use WIZnet modules (WIZ820io in particular) in conjunction with AVR Xmega on the hardware side of things. On the software side I haven't started in depth yet (just preliminary prototyping, because I'm busy doing MIDI control for THAT5171s right now). But the software basically sends/receives OSC bundles to/from the Xmega, which in turn parses them and deals with local SPI communication. The main trick for me right now is implementing zeroconf properly so that the end-user doesn't deal with any of the network stuff, but just plugs it in and it works.

I'm inclined to use Apple's Cocoa framework because once the model is there it literally is available on majority of devices out there. It could then also be ported to Windows with minimal/medium pain by using Cocotron.

Having said all that, one of my main objectives for this year is to develop what I call OSCAR (Open Sound Control Audio Remote), which is a tiny board with RJ-45 jack that sits between your local SPI/UART controlled gear (inside the chassis, as a part of the gear) and a PC app that then is enabled to control your gear via TCP/IP. The main beauty of this arrangement is that you upload a JSON file into that little board that describes what GUI you want and what element of the GUI sends/receives what SPI command. The PC app then just reads that description upon connecting to the board and initializes itself with the described GUI. Therefore the app doesn't actually need to contain gear-specific interface and be rigid in that regard. It could be generic and the same app could work for a multitude of devices. You could control an 8-channel preamp with it, as well as a LA-3A with motorized pots, as well as a temperature sensor outside your house. =) The JSON descriptor file could be generated on a website through a nice and easy step-by-step wizard.

It's a complex project to develop but we'll see how deep down the rabbit hole I'm able to travel... =)

PS: Now I actually hijacked the thread... =) Oops..

[JR.]

There are several processors with the TCIP stack built in, but I barely can repeat the jargon let alone make one.. It seems mimicking an IP address so amy web browser can interface should be pretty universal.

Not clear also what is the popular connector? Do the portable pad devices have RJ-45? I like the usb because you can also use it to suck power from wall powered computers to recharge batteries in portable devices.

/hijack]

JR

[mediatechnology]

John - IIRC there are some "web server" embeded products: http://netmedia.com/siteplayer/webserver/index.html

I think I've seen one embedded into an RJ-45 providing I^2C, SPI or serial out.

[JR.]

Thanks, nice, but at $25 a pop too expensive to design into a consumer product. I've seen <$5 micro's with the TCIP stack, so hardware is not the nut. For $25 per unit, I will learn how to make the code work, but not this weekend.

JR