• AD7888: FAQ

    FAQ

  • AD7888 input voltage range for reliable operation?

    Hello ADI support,

    I plan to use the AD7888 to sample dc voltages.  I will use the internal 2.5V reference.  I see on the data sheet that the analog input range is 0 to Vref volts.  My minimum dc input voltage to the AD7888 will be 25mV.  With a proper PCB…

  • AD7888: Using two 8 bit reads for the SCLK

    Q 

    How I can read ADC ad7888 data, if I use 8-bit SPI data register
    (microcontroller AVR)?
    May I read data for two 8-bit cycles?

     

    A 

    The SCLK for the AD7888 is also used for the internal bit comparisons...
    In order to avoid capacitor droop…

  • RE: AD7888 interfacing

    Hi, 

    Sorry for missing this item. I know this is long-overdue. However, we are clearing up some open items as others may find this useful.

    I noticed this similar thread in Student Zone. I hope this query already answered by this thread. 

    https://ez.analog…

  • AD7888 interfacing

    Hi team,

    I am working on a project where I need to interface AD7888 with a micro-controller (I am using MSP430F6736).

    The MCU has a SPI interface. Could anyone help me out with the steps from where I need to start and what steps do I need to follow…

  • AD7888 spike problem

    Hi,

    I have a problem using AD7888 with ATmega324PA.

    I am measuring sine voltages f=50Hz, so T= 20ms on 6 channels, 7 and 8 AIN are connected to GND

    SPI frequency is 125kHz and SPI mode is 3.

    What happens is that from time to time I get one spike…

  • Linux driver for ad7888

    I see there is linux kernel driver support for the ad7887, but the very similar ad7888 does not seem to have a driver anywhere.  Can I use the same driver?  Can I read all 8 channels using this driver, since the 7887 is only a 2 channel device?

  • AD7888采样几路电压（0.8-24V），想用电阻分压，请问多大电阻合适，还需要加跟随器吗？

    想用D7888采样几路电源电压，这几路电压分别为，1.8V，3.3V,24V，想用电阻分压，不知多大电阻合适。原来设计的是1M，实际来看，很不理想。想知道AD7888的输入阻抗有多大？自身是否带跟随器？

  • 各位工程师，请帮我看看AD7888怎么通道1怎么老是没有数据

    各位工程师，我在做AD7888实验时使用的是单片机控制AD7888的转换。端口定义在P0.0-P0.3。Measure函数就是AD7888的输入和输出函数，函数简单。Main函数就是把转换出来的值给发出来。很简单的测试程序就是出不来。请各位工程师帮忙看下。

    附上程序：

    #include<reg51.h>                   

    #include<intrins.h>

    #define uint unsigned int

    #define uchar unsigned char

    sbit…

  • What is the minimum frequency required for for SCLK ? the data sheet specs tell me the maximum fsclk = 2 MHz, but I cannot find a spec for minimum fsclk.

    Q 

    1. What  is the minimum frequency required for for SCLK ? the data sheet specs
    tell me the maximum fsclk = 2 MHz, but I cannot find a spec for minimum fsclk.

    2. What secret is behind the minimum spec for SCLK High Pulse width = 0.4 tsclk
    and for…