ADS1291

Hello ,

I have some questions about ADS1291 which i could not find the answers on datasheet.

1)IN2N, IN2P, PGA2N,PGA2P,RESP_MODN,RESP_MODP

Are these pins not connected or connected to some where?

2)Are we going to use same register table with ADS1292. Is there also 12 byte register table?

3)  05h CH2SET is exist but are we going to dont care?

Regards,

Fazıl

Thank you Tony

Hello Fazl ;

I am trying to use ADS1292 too ; could you share a working shematic please ; I have built a shematic but i am still need support.

Thank you inadvanced

Hector

Hello Hector,

i have used same schematics from ADS129X ECG Frontend Development board.

In shematics i used ADS1291, but also if you use frontends shematic (from datasheet) it will work perfectly.

If you send your own schematic we can discuss it.

Best Regards

Fazıl

Thank you fazl ;

I will send you the shematic on friday ; I am out of the office travelling to UK; infact I am good digital one ; but not analog one :) .

Do you have good experience with ECG analysis ?

By the way your name sound Spanish ; are you ? I am spanish too .

Regards

Hector

Hi, Fazil

I notice in your schematic you have a low pass filter with 66K cut off frequency. and in slau384, it also use a 66K cut off low pass filter, do you know why use a 66K cut off low pass.

and I notice there is a 100K resistor between pin 29 to pin30 in slau384 for drive out feedback. do you use drive out in your design? if not, is R1 and C2 necessary?

thank you for share your schematic.

David

Hi Fazil

I know many portable or handheld device don't use RLD. if you don't have limitation of the application, do you think RLD will improve overall performance? ( baseline stability as you mentioned)

Thank you 

David 

Hi Fazil

I have one more question, in SLAU384, there are 3 Ferrite Beads used for VCC.  L3, L4 and L7 all used 0603 package Max current is 2A. for current in mA circuit is it really necessary to use that big margin. I hope I can use 0402 package which is 500mA rated.

thank you,

David

Hello, 

I have one question about 1291 layout. there is no recommended land pattern pqfp32 in datasheet. in 1292 website there is an allegro package symbol, but my 16.2 dbdoctor couldn't upgrade it. I am not a professional layout guy. could anyone send a link or post an allegro 16.2 PCB editor symbol. appreciate your help.

David 

Hello Tony Calabria, Fazil Duman, and Yuan-Heng Lu!
I have followed this thread and the one where Lu shows his schematics, in my attempt to create a single-lead battery-driven low-energy ECG with rudimentary “patient-protection” based on ADS1291 and MSP430  micro controller. I would really appreciate if you, Tony, and anyone else would comment upon the schematic below. Will it work? What have I done wrong? What could be done better? I'm not an engineer by profession. I'm a surgeon but very interested in embedded design.
As you can see I have left IN3N and IN3P unconnected. Can I use them for leads-on/off control? If they can be used for that purpose I would appreciate to get some directions about how to accomplish that.
Further I want to kindly ask you, Fazil, to present your schematics in an other format. I have used .gif to present my schematics and I hope it will be easy to read. I have problems to read your schematics concerning your battery solution, which I find very interesting for my development. Thank you! Or  perhaps you can direct me to your source if you haven't developed them yourself.

Regards Bo

Hello Tony Calabria, Fazil Duman, and Yuan-Heng Lu!
I have followed this thread and the one where Lu shows his schematics, in my attempt to create a single-lead battery-driven low-energy ECG with rudimentary “patient-protection” based on ADS1291 and MSP430  micro controller. I would really appreciate if you, Tony, and anyone else would comment upon the schematic below. Will it work? What have I done wrong? What could be done better? I'm not an engineer by profession. I'm a surgeon but very interested in embedded design.
As you can see I have left IN3N and IN3P unconnected. Can I use them for leads-on/off control? If they can be used for that purpose I would appreciate to get some directions about how to accomplish that.
Further I want to kindly ask you, Fazil, to present your schematics in an other format. I have used .gif to present my schematics and I hope it will be easy to read. I have problems to read your schematics concerning your battery solution, which I find very interesting for my development. Thank you! Or  perhaps you can direct me to your source if you haven't developed them yourself.

Regards Bo

>> 1. These are no connects and should be pulled high through weak pull up resistors.

Does this mean that the unused pins on the ADS1291 are pulled high internally or that weak pullup resistors are required external to the pins?

Thank you!

Tony was referring to external pull-up resistors. :)

Regards,