Method and apparatus for phantom battery feed
View Patent ↗A method and apparatus is for providing a phantom battery feed to reduce power consumption in a differential amplifier circuit. A voltage signal is driven onto a telecommunications line using a first amplifier and a second amplifier. A phantom battery feed is performed during a negative cycle of the voltage signal. Performing the phantom battery feed comprises: supplying a negative supply terminal of the first amplifier with a supply voltage that is one-half of a full scale supply voltage; and supplying a positive supply terminal of the second amplifier with a supply voltage that is one-half of the full scale supply voltage.
1. A method, comprising:
driving a voltage signal onto a telecommunications line using a first amplifier and a second amplifier; and
performing a phantom battery feed during a negative cycle of said voltage signal, performing said phantom battery feed comprising:
supplying a negative supply terminal of said first amplifier with a supply voltage that is a portion of a full scale supply voltage; and
supplying a positive supply terminal of said second amplifier with a supply voltage that is a portion of said full scale supply voltage.
2. The method of claim 1 , further comprising dividing an operational voltage in half to create a phantom battery.
3. The method of claim 2 , wherein supplying a negative supply terminal of said first amplifier with a supply voltage that is one-half of a full scale supply voltage further comprises switching said negative supply terminal from said full scale supply voltage to said phantom battery.
4. The method of claim 3 , wherein switching said negative supply terminal comprises automatically switching said negative supply terminal in response to said voltage signal transitioning from a positive cycle to a negative cycle.
5. The method of claim 2 , wherein supplying a positive supply terminal of said second amplifier with a supply voltage that is one-half of said full scale supply voltage further comprises switching said positive supply terminal from a ground terminal to said phantom battery.
6. The method of claim 3 , wherein switching said positive supply terminal comprises automatically switching said positive supply terminal in response to said voltage signal transitioning from a positive cycle to a negative cycle.
7. An apparatus, comprising:
a first amplifier comprising a positive supply terminal and a negative supply terminal;
a first switch coupled with said negative supply terminal of said first amplifier, said switch being adapted to transition maid negative supply terminal from a full scale voltage source to a a portion of said voltage source;
a second amplifier comprising a positive supply terminal and a negative supply terminal and
a second switch coupled with said positive supply terminal of said second amplifier, said switch being adapted to transition said positive supply terminal from a full scale voltage source to a a portion of said voltage source.
8. The apparatus of claim 7 , further comprising a voltage source coupled to said first and second amplifier through at least one switch, the voltage source being capable of producing a half scale voltage supply.
9. The apparatus of claim 8 , wherein said voltage source is a linear regulator capable of producing said half scale voltage signal.
10. The apparatus of claim 7 , further comprising a switch control unit to perform automatic switching of said positive supply terminal and said negative supply terminal.
11. An apparatus, comprising:
a subscriber line; and
a line card electronically coupled with said subscriber line said line card to:
drive a voltage signal onto said subscriber line using a first amplifier and a second amplifier;
supply a negative supply terminal of said first amplifier with a supply voltage that is a portion of a full scale supply voltage; and
supply a positive supply terminal of said second amplifier with a supply voltage that is a portion of said full scale supply voltage.
12. The apparatus of claim 11 , further comprising at lest one switch, said switch being adapted to transition at least one of said negative supply terminal and said positive supply terminal to a one-half supply.
13. The apparatus of claim 11 , further comprising a switch control unit, said switch control unit to activate said switch to transition from a normal operation mode to a phantom battery operation mode in response to said voltage signal entering a negative cycle.
14. The apparatus of claim 11 , wherein said subscriber line is a telephonic line.
15. The apparatus of claim 11 , wherein said line card is housed in a central office.
16. An apparatus, comprising:
means for driving a voltage signal onto a telecommunications line using a first amplifier and a second amplifier; and
means for performing a phantom battery feed during a negative cycle of said voltage signal, performing said phantom battery feed comprising:
supplying a negative supply terminal of said first amplifier with a supply voltage that is a full scale supply voltage; and
supplying a positive supply terminal of said second amplifier with a supply voltage that is a portion of said full scale supply voltage.
17. A computer readable program storage device encoded with instructions that, when executed by a computer, performs a method, comprising:
driving a voltage signal onto a telecommunications line using a first amplifier and a second amplifier; and
performing a phantom battery feed during a negative cycle of said voltage signal, performing said phantom battery feed comprising:
supplying a negative supply terminal of said first amplifier with a supply voltage that is a portion of a full scale supply voltage; and
supplying a positive supply terminal of said second amplifier with a supply voltage that is a portion of said full scale supply voltage.
18. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 17 , further comprising dividing an operational voltage in half to create a phantom battery.
19. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 18 , wherein supplying a negative supply terminal of said first amplifier with a supply voltage that is one-half of a full scale supply voltage further comprises switching said negative supply terminal from said full scale supply voltage to said phantom battery.
20. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 19 , wherein switching said negative supply terminal comprises automatically switching said negative supply terminal in response to said voltage signal transitioning from a positive cycle to a negative cycle.
21. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 18 , wherein supplying a positive supply terminal of said second amplifier with a supply voltage that is one-half of said full scale supply voltage further comprises switching said positive supply terminal from a ground terminal to said phantom battery.
22. The computer readable program storage device encoded with instructions that, when executed by a computer, performs the method of claim 19 , wherein switching said positive supply terminal comprises automatically switching said positive supply terminal in response to said voltage signal transitioning from a positive cycle to a negative cycle.
23. A method, comprising:
driving a signal onto a telecommunications line using a first amplifier and a second amplifier;
supplying a first supply terminal of said first amplifier with a supply voltage that is less than a full scale supply voltage during a first cycle of said voltage signal; and
supplying a second supply terminal of said second amplifier with a supply voltage that is less than said full scale supply voltage during said first cycle of said voltage signal.
24. The method of claim 23 , further comprising supplying a full scale supply voltage to said first and second supply terminal during a second cycle of said voltage signal.
25. The method of claim 1 , wherein supplying said negative supply terminal of said first amplifier with a supply voltage that a portion of a full scale supply voltage comprises supplying said negative supply terminal a supply voltage that is one-half of a fall scale supply voltage.
26. The method of claim 1 , wherein supplying said positive supply terminal of said second amplifier with a supply voltage that a portion of a full scale supply voltage comprises supplying said positive supply terminal a supply voltage that is one-half of a full scale supply voltage.