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Author Topic: Invert output from 74hc139 2:4 decoder  (Read 506 times)
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Southern California
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I need a 2:4 decoder and the only one I can find is the 74hc139, but it's outputs are low/on high/off.
I need this reversed because the outputs from the decoder will drive Clock inputs to 4 74hc374's flip flops, which are active high.

Do I use some pnp transistors (and resistors?) to invert the signal, or is there a better way?

Thanks in advance.
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The 4555 is a dual 2 to 4 decoder with active high outputs, see http://www.datasheetcatalog.org/datasheet/philips/HEF4555BP.pdf.
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Thanks!

Chris
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