04401120 is referenced by 35 patents and cites 3 patents.

A programmable cardiac pacemaker pulse generator utilizing digital circuitry for controlling the provision of cardiac stimulating pulses. The pulse generator is capable of having the rate, the pulse width, the pulse amplitude, the refractory period, the sensitivity and the mode of operation programmed. In addition, the pulse generator can have the output inhibited and can respond to programming signals causing a threshold margin test to be performed, effects of closure of the reed switch overridden, a hysteresis function added and a high rate exceeding the normal upper rate limit programmed. Many of the programmable functions of the pulse generator can either be programmed on a permanent or a temporary basis. The pulse generator further includes means for signaling the acceptance of a programming signal, and means to reset the program acceptance circuit if extraneous signals are detected as programming signals. The program signal acceptance circuit performs several different checks on the detected programming signal including a parity check, an access code check and determining if the proper number of signals were transmitted within a given time. The timing circuit of the pulse generator includes a crystal clock oscillator and counter means for counting the clock pulses therefrom to determine the rate of the pacemaker. The pulse width of each pacemaker pulse is determined by using a voltage controlled oscillator in place of the crystal oscillator to obtain energy compensation due to the battery voltage decreasing with time.

Title
Digital cardiac pacemaker with program acceptance indicator
Application Number
957961
Publication Number
4401120
Application Date
August 12, 1981
Publication Date
August 30, 1983
Inventor
Ray S McDonald
St. Paul
MN, US
Jerome T Hartlaub
New Brighton
MN, US
Agent
Glenn W Bowen
Reed A Duthler
Joseph F Breimayer
Assignee
Medtronic
MN, US
IPC
A61N 1/36
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