Implantable receiver circuit

A circuit for use in an implantable device which provides pulse signals to electrically stimulate bodily tissue, said device including receiver means for detecting electrical signals applied external to said body but proximate thereto and for providing said detected signals to said circuit, said signals being radio frequency alternating current energy bursts occuring at a determined rate and magnitude, said circuit comprising:

• a pair of oppositely poled rectifiers each coupled to said receiver means;
• a filter for each rectifier for filtering the radio frequency from the signals provided by that rectifier to provide a pair of opposite polarity pulse series signals;
• an output capacitor electrically coupled between one of said filters and said bodily tissue;
• and
• a semiconductor switching device having a pair of main electrodes coupled between the junction of said one filter and said capacitor and a point of reference and having a control electrode coupled to the output of said other filter, said switching device being poled to discharge said capacitor during the interim between pulses applied thereto.