Delay circuit with temperature and voltage stability

摘要

Described are delay circuits that are relatively insensitive to changes in temperature and supply voltage. A delay circuit includes at least one inverter circuit made up of a pair of transistors. The inverter responds to voltage changes on the input terminal by providing corresponding inverse changes on the output terminal. The speed at which the inverter responds to voltage changes on the input terminal depends upon the ability of one or both transistors to conduct current to or from the output terminal. The ability of one or both transistors in the inverter to move charge to or from the output terminal is restricted to reduce the switching speed of the inverter, thus imposing a delay on the input signal. Further, the restricted current is provided at a reference level that is relatively insensitive to temperature changes and supply-voltage fluctuations.