Transceiver interface reduction
View Patent ↗A transceiver interface operating in accordance with the USB protocol includes a reduced number of pin outs by replacing a logic pair of single ended outputs V p and V m with a sole single ended zero output Se 0 . The interface is intended to form part of a USB device incorporated in apparatus such as a cellular radio telephone.
1. A transceiver interface connectable, in use, to a cable, the interface including an input for receiving a pair of signals from said cable, and a logic circuit connected to the input having a single logic output line, wherein the single logic output line of the logic circuit has a first output state where both signals are below a predetermined level and a second output state where either or both signals exceed the predetermined level and wherein the logic circuit is a NOR gate.
2. An interface as claimed in claim 1 , wherein the first output state is indicative of a single ended zero state.
3. An interface as claimed in claim 1 , wherein the second output state is indicative of a non-single ended zero state.
4. An interface as claimed in claim 2 , wherein the second output state is indicative of a non-single ended zero state.
5. A serial bus device including a transceiver interface as claimed in claim 2 .
6. A serial bus device including a transceiver interface as claimed in claim 3 .
7. A serial bus device including a transceiver interface as claimed in claim 1 .
8. A device as claimed in claim 7 , wherein the device includes an application specific integrated circuit having a single physical connection to said logic output line.
9. A mobile radio telephone including a device as claimed in claim 8 as dependent therefrom, wherein the application specific integrated circuit also provides mobile telephony functions.
10. A device as claimed in claim 8 , wherein the bus is Universal Serial Bus.
11. A device as claimed in claim 7 , wherein the bus is Universal Serial Bus.
12. A mobile radio telephone including a device as claimed in claim 11 as dependent therefrom, wherein the application specific integrated circuit also provides mobile telephony functions.
13. A transceiver interface connectable, in use, to a cable, the interface including an input for receiving a pair of signals from said cable, and a logic circuit connected to the input having only a single logic output line, wherein the logic circuit has a first output state where both signals are below a predetermined level and a second output state where either or both signals exceed the predetermined level and wherein the logic circuit is a NOR gate.
14. An interface as claimed in claim 13 , wherein the first output state is indicative of a single ended zero state.
15. An interface as claimed in claim 14 , wherein the second output state is indicative of a non-single ended zero state.
16. An interface as claimed in claim 13 , wherein the second output state is indicative of a non-single ended zero state.
17. A serial bus device including a transceiver interface as claimed in claim 13 .
18. A device as claimed in claim 17 , wherein the device includes an application specific integrated circuit having a single physical connection to said logic output line.
19. A mobile radio telephone including a device as claimed in claim 18 , as dependent therefrom, wherein the application specific integrated circuit also provides mobile telephony functions.
20. A device as claimed in claim 17 , wherein the bus is Universal Serial Bus.