04844076 is referenced by 437 patents and cites 3 patents.

A temperature responsive transmitter is disclosed. The transmitter utilizes a unique circuit design that allows encapsulation in an ingestible size capsule. The inventive circuit design uses a one transistor inverting amplifier with a tank circuit forming the link between the transistor's collector and the battery. The tank circuit is tuned to provide a lagging capacitive load which causes the inverting amplifier to oscillate. The tank circuit contains a coil inductor that emits a near field magnetic communications field containing temperature information. The ingestible size temperature pill can be configured in a rechargeable embodiment. In this embodiment the pill uses the inductive coil in the tank circuit as the magnetic pickup to charge a rechargeable nickel cadmium battery.

Title
Ingestible size continuously transmitting temperature monitoring pill
Application Number
7/236885
Publication Number
4844076
Application Date
August 26, 1988
Publication Date
July 4, 1989
Inventor
Arthur F Hogrefe
Laurel
MD, US
Jeffery C Lesho
Brookeville
MD, US
Agent
Howard W Califano
Robert E Archibald
Assignee
The Johns Hopkins University
MD, US
IPC
A61B 5/07
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