CrazyEngineers
  • AD633 Multiplier Problem

    syee10

    Member

    Updated: Oct 26, 2024
    Views: 1.2K
    Hi,

    I am designing a power meter which using the multiplier LM331 to multiply the Voltage and Current signal. The voltage and current signal will be go through the sample and hold circuit and the output of the sample and hold will be go into the LM331 multiplier. Power, P=VIcos(angle) and the LM331 having a transfer function of output W = [(X1-X2)(Y1-Y2)/10V]+Z. The problem is for example V=3V and I=2A, Output should be 6W(ignoring the cos(angle)). Due to the transfer function of LM331 i will never get the output 6W that i want. So anyone there can help me out? =)
    0
    Replies
Howdy guest!
Dear guest, you must be logged-in to participate on CrazyEngineers. We would love to have you as a member of our community. Consider creating an account or login.
Replies
  • shreyasm89

    MemberOct 5, 2010

    I don't think you can't ignore the power factor because that will denote the phase shift between vlt. & current. If you could explain how you got the transfer probably we could help you out. As ther are 2 inputs(X1 & X2) is 'Z" the o/p impedance of LM331?
    Are you sure? This action cannot be undone.
    Cancel
  • syee10

    MemberOct 5, 2010

    The transfer function W=[(X1-X2)(Y1-Y2)/10V]+Z is from the datasheet of AD633. Z is the additional input allows the user to add 2 or more multiplier output. What i mean is the Instantaneous Voltage and Instantaneous Current. The result W of the multiplier should give me 3W if we assume the V=3V and I=2cos60=1A? But with the Transfer function in the multiplier it will never give me that answer? I had attached the datasheet of AD633 for your reference. Thanks =)
    Are you sure? This action cannot be undone.
    Cancel
  • shreyasm89

    MemberOct 5, 2010

    What are x1 & X2 as well as Y1 & Y2?
    Are you sure? This action cannot be undone.
    Cancel
  • syee10

    MemberOct 5, 2010

    X1X2 and Y1Y2 are differential Input. For example if i want to multiply 3X2 it will be X1=3 and Y1=2. X2 and Y2 will be grounded as 0?
    Are you sure? This action cannot be undone.
    Cancel
  • shreyasm89

    MemberOct 8, 2010

    I think judging by the transfer function your power meter is givung o/p in terms of dB? Am I right?
    Are you sure? This action cannot be undone.
    Cancel
Home Channels Search Login Register