Oblon, Fisher, Spivak, McClelland & Maier
Semiconductor circuit device
 A semiconductor circuit device comprises a first depletion type n-channel insulated gate field effect transistor (hereinafter referred to as IG-FET) having its gate and source electrodes connected to each other, a second depletion type n-channel IG-FET connected between the source electrode of the first n-channel IG-FET and a positive power source and having its source and gate electrodes connected to each other, an enhancement type n-channel IG-FET connected between the source electrode of the first IG-FET and ground and having its gate electrode connected to an input terminal, an output terminal connected to the drain electrode of the first IG-FET, and a capacitor connected to the above-mentioned output terminal and ground. When a potential on the above-mentioned input terminal is dropped down to zero volt, the first depletion type IG-FET is abruptly shifted to the ON state, causing the capacitor to be abruptly charged by a positive power source. When the potential on the above-mentioned input terminal is raised to a predetermined positive level, the capacitor is slowly discharged through a zero-volt channel i.e. a remaining channel of the first depletion type IG-FET whose gate electrode is biased to zero volt. 
Tokyo Shibaura Electric Co., Ltd.
H G G
H03K G11C G11C
inventional inventional inventional
Kenji Kazunori
Yoshida Oouchi