Binary to BCD converter

[kyutekyute101]

Hi all
I am now using 74185AN ( binary to BCD converter) for my project and i found out that output of the IC do not give correct BCD format. If the input of binary value is 5 ( L LHLH ) and then the output BCD format will be the same . but in stead it gives ( HHLL HLLL ) . (don't care the first 3 MSB).

How will i need to do to have the correct one??
pls reply me.

Thanks..

 

[RadioRon]

According to the data sheet I have, the IC is working as it should if it is putting out HHLL HLLL as you say it is. I note that the IC is supposed to convert BCD bits 1 to 5 while bit 0 bypasses the IC. In other words, when you hook it up, the least significant bit of your BCD word does not go through the IC, it bypasses it to go directly to your binary output. The first input bit of the IC is the second bit of the BCD word, the one with a weighting of 2. The first output bit of the IC, called Y1 is in fact bit 1, not bit 0. So the IC is not connected to the least significant bit.

To wire it up correctly, use the least significant bit of your bcd word as the least significant bit of your binary word without passing it through the IC. Then hook up the remaining bits through the IC.

The way you have it hooked up now, it thinks that your input is actually BCD value of 10 or 11, so the output is trying to bit binary 16 or 17.

 

[kyutekyute101]

Thanks alot...RadioRon..Now your idea does really work for me...........