Hi everyone,
I was reading the below link on the Standard Product of Sums (SPOS): http://www.allaboutcircuits.com/vol_4/chpt_7/9.html
(It starts at around this part
The answer is (A + B + C) (A' + B' + C') and I know we want the sensors to detect the flame equally. So why is it that A OR B OR C logic works? Shouldn't it be A AND B AND C? Because then A and B and C would have to be equal for the output to be 0, which is what we want right?
I'm sorry if I don't make sense, English isn't my first language, so if you have any questions, please ask. Thanks in advance!
I was reading the below link on the Standard Product of Sums (SPOS): http://www.allaboutcircuits.com/vol_4/chpt_7/9.html
(It starts at around this part
I understand how to calculate the SPOS, but I don't understand the logic behind the example they give.If all three sensors are operating properly, they should detect flame with equal accuracy. Thus, they should either all register "low" (000: no flame) or all register "high" (111: good flame).
The answer is (A + B + C) (A' + B' + C') and I know we want the sensors to detect the flame equally. So why is it that A OR B OR C logic works? Shouldn't it be A AND B AND C? Because then A and B and C would have to be equal for the output to be 0, which is what we want right?
I'm sorry if I don't make sense, English isn't my first language, so if you have any questions, please ask. Thanks in advance!