Backup battery power supply for microprocessor based telephones
First Claim
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1. A battery backup power supply for use with an associated line connected telephone, said battery backup power supply comprising:
- a regulated voltage input connected to a voltage regulator included in said telephone;
a battery;
control means including circuit connections to said regulator and to said telephone line, operated in response to a voltage on said telephone line insufficient to power said telephone to connect said battery to said voltage regulator; and
a low pass filter connected across said telephone line operated to block voice signals on said telephone line from said control means.
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Accused Products
Abstract
A circuit arrangement for use in telephone instruments which require battery backup for memory retention and microprocessor operation during such procedures as pulse dial address signalling where no power can be supplied by the telephone subscriber'"'"'s line. Bipolar solid state circuitry may be used to provide the necessary backup power supply during these periods.
30 Citations
7 Claims
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1. A battery backup power supply for use with an associated line connected telephone, said battery backup power supply comprising:
- a regulated voltage input connected to a voltage regulator included in said telephone;
a battery;
control means including circuit connections to said regulator and to said telephone line, operated in response to a voltage on said telephone line insufficient to power said telephone to connect said battery to said voltage regulator; and
a low pass filter connected across said telephone line operated to block voice signals on said telephone line from said control means. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- a regulated voltage input connected to a voltage regulator included in said telephone;
Specification