SN74185A 16Bit Binary-to-BCD

Yuta Nishie

Genius 3720 points

Hi,

Our customer has a question about SN74185A.

If you know the cause of the following phenomena, could you please tell me?

There is a circuit example of 16bit Binary-to-BCD Converter in the data sheet of SN74185 obtained on the net.

Our customer used this as a reference, and create the circuit with Quartus.

Then, where the value should change from 4999 to 5000, it changed from 4999 to 8000.

I don't think there is a problem with the circuit I created, but please tell me the reason why this phenomenon occurs.

https://pdf1.alldatasheet.com/datasheet-pdf/view/98236/TI/SN74185A.html

0245.Bin2BCD16_Schematic.pdf

Best Regards,

Nishie

over 3 years ago

+1 Clemens Ladisch over 3 years ago

Guru 283370 points

The chip at the bottom must output 00101. but this combination of outputs does not appear in the function table. So that circuit in the datasheet is wrong.

I'd guess that the chip at the bottom must be shifted left by one bit.

The SN74185A is discontinued and no longer supported.

0 Yuta Nishie over 3 years ago in reply to Clemens Ladisch

Genius 3720 points

Hi Clemens Ladisch,

Thank you for your reply.

Best Regards,

Nishie

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

Logic

Logic forum

SN74185A 16Bit Binary-to-BCD