System and method for power supply preservation in a personal health monitor

A method of operation for a personal health monitor having an isolation relay requiring the supply of power upon the condition that the supply of a first power source is disconnected, the method comprising the steps of:

• operating the personal health monitor with a second power source, and,
• upon the condition that the voltage level is at or below a minimum operation level,
• storing information on the personal health monitor indicating that the supply of power from the second power source to one or more components of the personal health monitor will be disconnected,
• disconnecting the supply of power from the second power source to one or more components of the personal health monitor, and
• maintaining the isolation relay closed by providing the isolation relay with a supply of power from the second power source,
• whereby the isolation relay can remain closed and the personal health monitor can be restarted from the first power source if the first power source is restored.

In a personal health monitor of the type that utilizes a first power source and further in which the personal health monitor includes:

• one or more components for the measurement of one or more clinical parameters of a patient,
• a rechargeable backup battery power source adapted to provide power to the one or more components of the personal health monitor upon the condition that the first power source is disconnected or fails,
• an isolation relay coupled to the first power source, the isolation relay adapted to disconnect the personal health monitor from the first power source in the absence of a supply of power to the isolation relay,
• a voltage detector responsive to the output of the rechargeable backup battery power source, and
• a power switch coupled between the outputs of the first power source and the rechargeable backup battery power source and the one or more components of the personal health monitor, a controller for preserving operation of the personal health monitor, said controller coupled to the rechargeable battery backup power source, the power switch, the voltage detector and the isolation relay, and further in which said controller comprises:
• means for opening the power switch to disconnect the rechargeable backup battery power source from the components of the personal health monitor upon detection by the voltage detector of a voltage at or below a minimum operation level,
• means for supplying power to the isolation relay to enable the isolation relay to remain closed, whereby the personal health monitor can be restarted from the first power source.

A system for providing an uninterruptible power source for a personal health monitor of the type that utilizes a first power source and further in which the personal health monitor includes one or more components for the measurement of one or more clinical parameters of a patient, the system comprising:

• a rechargeable backup battery power source adapted to provide power to the one or more components of the personal health monitor upon the condition that the first power source is disconnected or fails,
• an isolation relay coupled to the first power source, said isolation relay adapted to disconnect the personal health monitor from the first power source in the absence of a supply of power to the isolation relay,
• a voltage detector responsive to the output of said rechargeable backup battery power source,
• a power switch coupled between the first power source, the output of said rechargeable backup battery power source and the one or more components of the personal health monitor, and
• a controller coupled to said rechargeable battery backup power source, said power switch, said voltage detector and said isolation relay, said controller comprising:
• means for opening said power switch to disconnect said rechargeable backup battery power source from the components of the personal health monitor upon the detection by said voltage detector of a voltage at or below a minimum operation level,
• means for supplying power to said isolation relay to enable said isolation relay to remain closed, whereby the personal health monitor can be restarted from the first power source.