Sunday, April 21, 2019
Atanua| 74ls85 4-BIT MAGNITUDE COMPARATOR
Today's blog is about the 74ls85 TTL. To build a circuit with this chip you will need two 4 pack dip switches and three led's. A datasheet is below. This TTL will compare the combined value for the 4-bit input of A inputs vs the B 4-bit inputs. The output will send a high to only one of the led's, AB depending on the condition.
Comparison of words greater than 4-bit can be accomplished by cascading 'ls85 as described in the data sheet. The 74ls85 compares two separate 4-bit words, or numbers, coming from two different sources, such as counter, shift register, etc., including hard-wiring one number on the chip. One 4-bit word is placed on the inputs A0 thru A3, with the Least Significant Bit on A0. The other word is placed on inputs B0 thru B3 A 7 segment display can be implemented in the circuit by joining the inputs to a decoder that leads to the display. This will show numeric values.
There are tons of electronic modules available. Here are three of our favorites available in our Tindie Marketplace store now. These three m...