Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Gates or IC to use to convert 1x 4 bit 2x 4 bit

  1. Jan 3, 2012 #1
    example 1111 = 15 is there a circuit to separate output binaries 0001(1) and 0101(5) in input 1111(15)?
  2. jcsd
  3. Jan 3, 2012 #2
    A binary to BCD decoder does what you want. There were the 74LS/HC/HCT185 ICs, but it might be difficult to get one today.
  4. Jan 3, 2012 #3
    my question was to separate 2 binary digits out of the 4 or 5 bit binary. to display it using 2x 7 segment
  5. Jan 4, 2012 #4
    Binary Coded Decimal (BCD) is the same as binary for 0-9, but then it carries to 10 and not to 0A. So this is exactly what you want. A single 74185 chip will decode up to 6 bits of binary to 2 digits of BCD.
    (You have to add one or two BCD-7segment decoder/drivers)

    Of course you could use a microcontroller or a programmable logic chip, as discussed here.

    Other alternatives:
    - simply use 5 Leds and learn to read binary
    - use a BCD-7seg decoder/driver with defined output for input a-f and learn to read this (74247, iirc)
    - two digit octal display with two standard BCD-7seg decoder/drivers
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook