Power supply

• US 3,871,383 A
• Filed: 09/25/1973
• Issued: 03/18/1975
• Est. Priority Date: 09/25/1973
• Status: Expired due to Term

• Current Assignee: Exide Electronics Corporation (Exide Electronics Group, Inc.)
• Original Assignee: Jin W. Lee
• Inventors: Lee, Jin W.
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US05/400,503
• Time in Patent Office: 539 Days
• Field of Search: 128/419P,419PS,419R,421,422,423 307/46,48,51,60,71,87,297 320/16,33
• US Class Current: 607/34
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/378 Electrical supply
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 9/061 for DC powered loads

Abstract

A redundant power supply for a body organ stimulating device having at least two parallel branches. Circuit means are provided which are operatively connected to the output terminals of the power supply and to each parallel branch thereof and are responsive to the voltage across the output terminals of the power supply falling to a predetermined value for automatically serially interconnecting the power sources of the power supply.

Claims

1. In a power supply having a pair of power output terminals, the power supply being connectable to the power input terminals of a body organ stimulating device, the power supply further comprising at least two voltage sources connected in parallel, each voltage source being connected to the power output terminals and having substantially the same initial terminal voltage whereby initially the power output terminals of the power supply are supplied with a voltage substantially equal to the terminal voltage appearing across each voltage source of the power supply, the improvement comprising:

voltage regulating means operatively connected to the power output terminals of the power supply and to each voltage source thereof and being responsive to the voltage appearing across the output terminals of the power supply falling to a predetermined value less than the initial terminal voltage of the voltage sources for automatically serially interconnecting each of the voltage sources and the power output terminals of the power supply, and for maintaining the voltage across the power output terminals of the power supply substantially equal to the predetermined value.

2. In a power supply as defined in claim 1 wherein the voltage regulating means includes:

a. means having a variable impedance interconnecting each of the voltage sources of the power supply and when activated providing a series connection between the voltage sources and the power output terminals of the power supply with the voltage appearing across the power output terminals in such series configuration being substantially equal to the sum of the voltages appearing across each of the voltage sources of the power supply minus the voltage drop across the means having a variable impedance;

b. voltage sensing means operatively connected to the power output terminals of the power supply and to the means having a variable impedance for continuously sensing the voltage across the power output terminals of the power supply and being responsive to the voltage across the power output terminals of the power supply falling to a predetermined value for activating and continuously varying the impedance of the means having a variable impedance thereby maintaining the voltage across the power output terminals at the predetermined level; and

c. means for rendering ineffective the parallel connection of the voltage sources when a series connection thereof is effected.

3. In a power supply as defined in claim 1 including selectively actuable means operatively connected to the voltage regulating means for controlling the operation thereof and for causing it to effect a series interconnection of the voltage sources and the power output terminals of the power supply irrespective of the voltage appearing across the power output terminals of the power supply.

4. In a cardiac pacer having a voltage responsive, variable rate pulse generator a redundant power supply comprising:

a. a pair of power output terminals;

b. a first voltage source coupled to the pair of power output terminals;

c. a second voltage source coupled to the pair of power output terminals and connected in parallel with the first voltage source, the first and second voltage sources initially supplying a voltage to the pair of power output terminals substantially equal to the terminal voltages thereof; and

d. voltage regulating means coupled to the pair of power output terminals for maintaining the voltage across the pair of power output terminals at a predetermined substantially constant value less than the initial terminal voltages of the first and second voltage sources in response to the voltage appearing across the pair of power output terminals falling to the predetermined value, the voltage regulating means comprising;

i. means havIng a variable impedance interconnecting the first and second voltage sources and when activated providing a series connection between the first and second voltage sources and the pair of power output terminals, with the voltage appearing across the pair of power output terminals in such series configuration being substantially equal to the sum of the voltages appearing across each of the first and second voltage sources minus the voltage drop across the means having a variable impedance;

ii. voltage sensing means coupled to the pair of power output terminals and to the means having a variable impedance for continuously sensing the voltage across the pair of output terminals and for activating and continuously varying the impedance of the means having a variable impedance when the voltage across the pair of power output terminals falls to the predetermined value thereby maintaining the voltage across the pair of power output terminals at the predetermined level; and

c. means for rendering ineffective the parallel connection of the voltage sources when a series connection thereof is effected.

5. In a cardiac pacer as defined in claim 4 including:

a. selectively actuable means operatively connected to the voltage regulating means for controlling the operation thereof and for causing the voltage regulating means to interconnect the first and second voltage sources and the pair of power output terminals of the power supply in series irrespective of the voltage appearing across the power output terminals and for simultaneously causing the pulse providing means to operate at a continuous rate.

6. A cardiac pacer having the redundant power supply of claim 5 further including a diode connected across each voltage source of the power supply to provide conduction by-passing a voltage source in the event of open circuit failure thereof and to provide a shunt for reverse polarization of a voltage source.

7. In a cardiac pacer as defined in claim 4 including:

a. selectively actuable means operatively connected to the voltage regulating means for controlling the operation thereof and for causing the voltage regulating means to interconnect the first and second voltage sources and the pair of power output terminals of the power supply in series irrespective of the voltage across the power output terminals and for simultaneously causing the pulse providing means to operate in a continuous mode, the timing by an observer of pulses generated by the pulse providing means providing an indication to the observer of the voltage across the power output terminals when the voltage sources and pair of power output terminals are connected in series.