Fireplace Circuit
Description
The Acme Fireplace Company has hired you to redesign the fireplace control circuit for their latest residential gas fireplace. The fireplace burner is equipped with four thermal sensors that output a logic (1) whenever a flame is present. These sensors are connected to the fireplace control circuit which outputs a (1) to the emergency cut-off valve to keep the gas flowing (i.e., a zero will turn the gas off). The original design of the fireplace control circuit was quite simple. For the gas valve to remain on, all four sensors needed to output a logic (1). During field testing it was discovered that variations in gas pressure and humidity cause the thermal sensors to occasionally output a logic (0) even when a flame is present. This caused frequent unnecessary shut downs and constant customer dissatisfaction.
Conclusion Questions