# HT12e: How is this a 2¹² encoder?

I am using HT12E, for a rf transmitter circuit. As per the datasheet HT12E is a 2¹² encoder.

Ideally such an encoder must have 2¹² inputs and 12 outputs. In addition to that all the inputs should be 1 exclusively.

When i look at the IC, I see 12 inputs A0-A7 + AD8-AD11, which go into the transmission gate circuit of the IC.

Can someone help me understand this part of the working ?

• I haven't looked, but from your description it appears that "$2^{12}$ inputs" (your term) means instead "$2^{12}$ symbols." The 12 inputs make sense then. – jonk Jun 3 '19 at 15:52
• that appears to be a type of parallel to serial converter ... it encodes 12 inputs into a bit stream ... 12 inputs and 1 output – jsotola Jun 3 '19 at 15:54

A chip with 212 inputs would have $$\ ( {2 ^ {12}} ) ^{12} \$$ possible combinations.