Precision Data Converters

Browse by Tags

Precision Data Converters

Welcome to the Precision Data Converters Section of the TI E2E Support Community. Ask questions, share knowledge, explore ideas, and help solve problems with fellow engineers. To post a question, click on the forum tab then "New Post".

Sign In to Post
Tags
You have subscribed to this tag. To view or manage your tag subscriptions, click here.   Close
You have unsubscribed from this tag. To view or manage your tag subscriptions, click here.   Close
You are currently viewing:
DAC1220
Related Posts

  • Forum Post: Re: DAC1220 C1 & C2 pins

    Bob Benjamin
    Al, I don't understand why you are seeing a large settling time. It should be in the order of milliseconds with 15 milliseconds worst case. What kind of load do you have at the output? The caps do affect the settling time. There are register bits in the CMR that control fast settling behavior...
    on Nov 24, 2010

  • Forum Post: Re: Power of DAC1220 / 20 bit at lower main clock rates

    Bob Benjamin
    David, The DAC1220 was designed about 14 years ago when power consumption wasn't as big of an issue is it is today. So we really don't have detailed data on the DAC1220 that you would like to see. There is no data for any clock speeds less than 2.5MHz, but I would suspect it to be slightly...
    on Jun 7, 2011

  • Forum Post: Re: Power of DAC1220 / 20 bit at lower main clock rates

    Bob Benjamin
    David, Always feel free to ask, as often times we can give more information. At this time the best solution we have is the DAC1220. Best regards, Bob B
    on Jun 8, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi again, thanks for the fast reply, you are right, the INSR is the Command Byte, and apparently, I have been using the correct sequence with the DAC, even so, the DAC is not working, perhaps the times, in the datasheet. Because when you sent a operation(read,write) you must respect the times(t9,t10...
    on Nov 25, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi again, Well I finally have success with the DAC1220,now I understand its operation, I make a few tests and it works fine, thanks for all the explanations. There is only one problem left, right now I'm bulding a project with the DAC1220 and I need to work with microvolts(uV) so I decided...
    on Nov 26, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi Tony, First, thanks for your soon reply, well I will try it with your advice, but in case A or in case B, i mean: (A) I put the lower codes, and the exit change from 700uV, lets say for code 1--->704uV, for code 2--->708uV, etc. (B) I put the lower codes and the exit doesn't change...
    on Nov 28, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Pedro, Just a couple of other things. The quality of the cap and guard ring around the C1 and C2 caps are also very important to keep noise to a minimum. Review the layout recommendations in the application section of the datasheet. You may also want to review the DAC1220EVM user's guide for a...
    on Dec 7, 2011

  • Forum Post: Re: DAC1220 Serial interface

    Bob Benjamin
    1931435, Welcome to the forum! Before running the Reset pattern, you need to make sure that you have waited a sufficient amount of time for oscillator to have started, as for the Reset pattern to be detected there needs to be an internal timer available to determine that the pattern timing is valid...
    on Dec 9, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi Tony, Bob It's Daniel again, I just want to ask you something very particular, it's about the reset procedure of the DAC1220, apparently we are working properly with the DAC, and we obtain the real codes I mean( ideal codes with a error margin), but I was reading the datasheet, and it...
    on Dec 12, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Daniel, After RESET the device will go into SLEEP mode, so even if the DIO is 0, it will not change the output until the device is in NORMAL mode. When in SLEEP the output should be high impedance. You probably want to do a CALIBRATION first thing after RESET, which will place the device in NORMAL...
    on Dec 12, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Page 12 of the datasheet describes the modes, and sleep is the mode after a reset. After a self calibration the mode goes to normal, so I believe that there is a type on page 13. Best regards, Bob B
    on Dec 12, 2011

  • Forum Post: Re: DAC1220 Serial interface

    Bob Benjamin
    I would try lengthening the times a little as you are pretty close to the minimum high times. Best regards, Bob B
    on Dec 12, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi Bob, Thanks for the advice, I will do the calibration procedure but I have a doubt. I read the datasheet about the sequence for the calibration, but in the page 17 when you must change the bits MD for the operation mode, it says: Self calibration mode (No other bits should be changed in the...
    on Dec 13, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Daniel, You just go by the descriptions for default. Not all of the values apply or they are for commands and that is why there isn't a default value. Binary value '0010000000000001' or hex 0x2001. Best regards, Bob B
    on Dec 14, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi again Bob, Tony I write this message to inform you that we did the calibration procedure, but first, let me tell you what we are doing exactly, we are using two DACs (both 1220), and their outputs are connected to an intrumentation amplifier with gain=1, so we have at the output of the amplifier...
    on Dec 15, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Daniel, 800uV from the rail is pretty good. The output just can't get to the supplies as there is a transistor between. So you will see a number of codes that just don't appear to do anything close to the rails. The number of codes affected will be determined by whether you are running 16...
    on Dec 15, 2011

  • Forum Post: Re: DAC1220

    Daniel Bedoya
    Hi Bob Well, we follow almost all the considerations that you mention,except that we are using ceramic capacitors with these values C1=10nF, and C2=3.3nF(for the datasheet), but we are not using the guard ring, so maybe there is a problem in that part. But if we increase the values of the capacitors...
    on Dec 16, 2011

  • Forum Post: Re: DAC1220

    Bob Benjamin
    Daniel, Yes the guard ring and ground plane are very important. As this DAC is a delta-sigma there is a modulator and switching. The C1, C2 caps filter this noise. As it is impossible for me to see and know the frequency of the oscillation you are talking about it is hard for me to determine the source...
    on Dec 16, 2011

  • Forum Post: DAC1220

    Daniel Bedoya
    Hi, I just want to ask about the DAC1220 startup sequence, I'm having problems to understand the procedure, so maybe you can help me. The waiting period for the crystal oscillator and the SCLK reset pattern, is all fine, but the problem is in the step 3 because it says that the DAC1220 enters...
    on Nov 25, 2011

  • Forum Post: Re: DAC1220, reading process, OCR,FCR, DIR

    Daniel Bedoya
    Hi again, here I send a part of my code in assembly for the communication with the DAC, can you check the subroutines for the reading procedure, please?. The RET is for return, I mean the exit of the subroutine. I indicated in red, the fragment of the code for the communication with one of the DACs,...
    on Jan 13, 2012

  • Forum Post: Re: DAC1220, reading process, OCR,FCR, DIR

    Bob Benjamin
    Daniel, It is a little hard for me to follow your code, though it appears to be ok. The DAC1220 interface for the serial pin is bi-directional, so when you are writing and reading from the same pin a minimum of time (t9) is required between the last SCLK of the write and the first SCLK of the read...
    on Jan 13, 2012

  • Forum Post: DAC1220, reading process, OCR,FCR, DIR

    Daniel Bedoya
    Hi, I post a few weeks ago another problem that I had with the DAC1220, and finally I understand how it works, but I now have problems with the read operations, I try to read the DIR, after I sent a code to the DAC, but I couldn't, I used exactly the same procedure like in a write operation, because...
    on Jan 12, 2012

  • Forum Post: DAC1220

    Tom Burdick
    I have the DAC1220EVM and have it operarting quite nicely, however, the output amp rolls over when approaching max output. This is a property of the op-amp, as monitoring the DAC output directly, things go to nearly the rails. Can you suggest a more modern op-amp that will not roll over and be single...
    on Mar 30, 2012

  • Forum Post: RE: DAC1220 EVM Board Startup Difficulties

    Bob Benjamin
    Michael, Sorry for the delay in response. A couple of things. In regards to connections, you were detailed on how you made your connections to the EVM connector except for the SCLK and SDIO settings. SCLK should connect to the serial connector pin 3. SDIO should connect to serial connector pin 11....
    on May 19, 2012

  • Forum Post: RE: DAC1220 communication problem

    Bob Benjamin
    Albin, Were you able to achieve any success in resolving your issues? If not, can you send us the information Tom requested? Also, it would be good to know the commands that you are giving to initialize the device. Best regards, Bob B
    on May 19, 2012
12

All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.

Content on this site may contain or be subject to specific guidelines or limitations on use. All postings and use of the content on this site are subject to the Terms of Use of the site; third parties using this content agree to abide by any limitations or guidelines and to comply with the Terms of Use of this site. TI, its suppliers and providers of content reserve the right to make corrections, deletions, modifications, enhancements, improvements and other changes to the content and materials, its products, programs and services at any time or to move or discontinue any content, products, programs, or services without notice.

TI Worldwide | Contact Us | my.TI Login | Site Map | Corporate Citizenship | mobile m.ti.com (Mobile Version)

TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs and
embedded processors, along with software, tools and the industry’s largest sales/support staff.

© Copyright 1995-2013 Texas Instruments Incorporated. All rights reserved.
Trademarks | Privacy Policy | Terms of Use