Re: need L290 substitute

Hal Murray wrote:
Why is it whenever I find the PERFECT chip for something, it turns out to be discontinued? I found the L290 from SGS-Thompson, an old part that converts quadrature encoder signals to bipolar voltage proportinal to frequency. It looks like it could be real difficult to get this part, except from the vultures. It is basically a double F-V converter, so it produces a voltage proportional to count rate, with the sign of the output indicating the direction the encoder is turning. I think I know how to do this with 2 F-V converters and some logic, but I can't get it below about 6 chips. Does anyone know of a replacement for the L290 or L290B that does the same quadrature to bipolar voltage conversion?

CPLD?


That can get you from one obsolescence problem into the next. Programmable logic doesn't have a particularly long life span and it's expensive.


How fast do the bits change? Can you do it in software
with a PIC/AVR/8051? ...


Way to go.


... Pick your favorite.


Which one comes with teriyaki sauce?

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Relevant Pages

  • Re: need L290 substitute
    ... I found the L290 from SGS-Thompson, an old part that converts quadrature encoder signals to bipolar voltage proportinal to frequency. ... It is basically a double F-V converter, so it produces a voltage proportional to count rate, with the sign of the output indicating the direction the encoder is turning. ...
    (sci.electronics.design)
  • Re: need L290 substitute
    ... an old part that converts quadrature encoder ... signals to bipolar voltage proportinal to frequency. ... It is basically a double F-V converter, ...
    (sci.electronics.design)