In this application, three 2-input OR gates are combined to produce a 4-input OR gate function as shown in Figure 8-1. The fourth gate can be used for another application in the system, or the inputs can be grounded and the channel left unused.

The SN74LVC7032A-Q1 is used to directly control the Enable pin of a fan driver. The fan driver requires only one input signal to be HIGH before being enabled, and should be disabled in the event that all signals go LOW. The 4-input OR gate function combines the four individual overheat signals into a single active-high enable signal.

Temperature sensors can often be spread throughout a system rather than being in a centralized location. This would mean longer length traces or wires to pass signals through leading to slower edge transitions. This makes the SN74LVC7032A-Q1 an excellent choice for the application since it has Schmitt-trigger inputs that do not have input transition rate requirements.