• Problem with the AD7685.

    Problem with the AD7685. The conversion is only on 12 bits. I work in mode 3
    wire with no busy indicator. The last 4 LSB bits are always high. I read in
    hexa 0xXXXF. What are the conditions which may cause this problem.

     

    The ADC needs separate…

  • AD7685: Supplied with VDD, but Vref and Vio removed

    I use AD7685 with VDD=3.3V and Vref=Vio=1.8V.  When I remove power from Vref
    and Vio but keep VDD at 3.3V:
    Will this harm the IC in any way?
    Will there be any voltage's present on SPI pins or will they be pulled hard low?
    When Vref and Vio power…

  • VDD Power Ramp Up Issue for AD7685

    We had designed AD7685 in multi-channel AI/AO card project and configure AD7685 as CS mode 3-wire with busy. Detail please find below schematic.

    As datasheet mention, the VDD and VIO are independant and SDO should be high impedance until completion conversion…

  • AD7685

    I am using AD7685 to read a CMOS linear camera sensors. The sensor has 512 pixels. It reads 512 consecutively at 125Khz, wait some time, then read it again. 

    The first few AD readings, for some reasons, are always off a little bit. The first reading has…

  • AD7685 startup issue,

    I am running the AD7685 at 3-wire WITH busy indicator setup. 

    After power up, some readings I get are wrong, If I do the following, the problem is corrected:

    1. touch the AD7685 with my finger. 

    2. blow air on the chip from my mouth. 

    3. let it run for a…

  • RE: AD7685

    I'll try to move this on this community (+) 问答 - 精密转换器专区 - EngineerZone (analog.com). So someone here can further assist you. 

    Thanks,

    Jellenie

  • ad7685 diode clamp required

    The opam has power supply of 8, and -12VDC. 

    In some conditions, the output can swing to 8 and -12v. 

    Will that damage the AD7685? We have noticed issues with the readout is shifted downward. For example, 0vdc shows up as 60000, 5V shows up at 30000. 0…

  • AD7685的通信时序

    依据AD7685的数据手册,三线SPI通信,将SDI拉高,SPI通信前有一段转换时间,Tconv。

    但是,我用示波器抓取DEMO板的SDO,CONV,SLK三线的电平情况,发现CONV并没有一段转换时间。

    请问是否需要这段转换时间。

  • ad7685 NO busy indicator mode

    How long do I hold the CNV high ? Should I use the MAX time in the spec?