Patent ID: 7230456

Claim:
A detector circuit comprising: an input terminal; a ground terminal; an output terminal; a first device coupled to the input and output terminals, to pull the output terminal to a first output voltage when a supply voltage below a supply threshold is applied to the input terminal, and the first device being configured to have no substantial change in current consumption after the supply voltage applied to the input terminal has exceeded the supply threshold; the first device comprises a depletion NMOS device with a drain of the depletion NMOS device coupled to the input terminal, and a source of the depletion NMOS device coupled to a gate of the depletion NMOS device and the output terminal; and a second device coupled to the input, ground and output terminals, to pull the output terminal to a second output voltage when the supply voltage applied to the input terminal exceeds the supply threshold, the second device comprises a NMOS device with a drain of the NMOS device coupled to the output terminal, a gate of the NMOS device coupled to the input terminal, and a source of the NMOS device coupled to the ground terminal.