Abstract: A multiple input window detector is disclosed which includes a balance pair of common base PNP transistors having multiple emitters connected to respective inputs for comparing either input to an upper threshold level established by a voltage divider. A pair of common emitter PNP transistors compare the inputs to a lower threshold level. The two outputs of each comparator are interconnected and the combined currents control an output stage which is driven to one state when both inputs are within the window established by the divider and is driven in the other state if either input is outside the window.