• AD637: Pin layout

    The AD637 surface mount package (R) has 2 more pins than the DIP
    (D) and (Q) Packages. Unfortunately the data sheet does not indicate
    where the Power Supply pins are on the surface mount package.
    On the DIP packages -Vs is on pin 10 an…
  • AD637 simulation failed

    Hi,

    I'm currently working in a tomography project which required to acquire RMS measurements between two electrodes. The sine wave frequency is between 10kHz-200kHz. In the experiment I observed the maximum potential difference is 500mV. I tried an example…

  • AD637的问题

    最近在做一个交流有效值转换的东西,用到了ad637,电路是按照datasheet上的标准RMS连接做的。CAV取得是10uF。BUFFIN、COMMON、OUTPUT OFFSET接地。用信号发生器产生一个频率为200K峰峰值为2V的正选信号,经过AD637后,用万用表直接测量AD637的输出端为0.685V,跟理论的0.707V相差比较大,并且测量数据不稳定,相同的条件下再次测量变为0.662V,数据还一直变动,有时是0.702V。想问下这是怎么回事,请高手赐教。

  • AD637 max output current

    Anyone have an idea of the max output current on the AD637. The datasheet shows a min output current but nothing for the max. Thanks

  • 急,有关AD637使用

    用AD637进行交流测量时,用3458A测量637输入,34410测637输出。两者相除得到转换系数,发现2V有效值输入和200mV输入差别很大,有百分之几的差别,什么原因,我试了3片637都有这种情况。

  • problem with AD637 Chip select

    Hi, I'm using AD637BR with a circuit that controls the chip select pin. I implemented a 2 pole filter using the internal buffer (pins 1 and 16) that follows the RMSOUT (pin 11).

    I found out that, when chip is enabled, everything works fine but when…

  • AD637 convergence problem on Orcad pspsice

    I have imported the model of AD637 in orcad suite.

    I create a simply circuit, but pSpice return the following error:

    "ERROR(ORPSIM-15659): Discontinuing simulation due to convergence problem"

    I used this

    .OPTIONS GMIN=5E-17 for best output…

  • AD637 Scale Factor Trim

    Hello,

    I have a questions on the scale factor trim described on page 8 of the datasheet. A resistor R4 (147 ohms)  is placed in series with the input and a variable resistor R3 (1K pot) is between the output and the DEN input

    1) Is resistor R4 in the…

  • AD637响应时间

    AD637的datasheet中关于均值电容和滤波电容选择后的响应时间存在疑惑:

    (1)datasheet手册中图13右侧纵坐标标注的“FOR 1% SETTLING TIME IN SECONDS MULTIPLY READING BY 0.400

    ”这个是什么意思呢?表格7中“1% Settling Time”是什么意思呢?

    (2)我的需求是输入信号有效值范围交流正弦波100mv到5V,频率为固定的20kHz,要做RMS-TO-DC转换,转换时间需要再1ms左右,应该怎么选择电容值呢?

  • Is AD637 dB calibration without buffer possible ?

    In the AD637 data sheet Rev.L p18 fig.20 the circuit to set the reference dB = 0 point uses the AD637 integrated buffer and two external op-amps, one of which is obsolete. In any case this seems to be over-complex just to level shift a dc voltage.