Transmission cable structure for GHz frequency band signals and connector used for transmission of GHz frequency band signals

• US 7,113,002 B2
• Filed: 05/14/2004
• Issued: 09/26/2006
• Est. Priority Date: 05/15/2003
• Status: Expired due to Fees

• Current Assignee: Fujikura Limited
• Original Assignee: Fujikura Limited
• Inventors: Koyasu, Osamu, Usami, Tamotsu, Akiyama, Yutaka, Ueda, Chihiro, Otsuka, Kanji
• Primary Examiner(s): Tan, Vibol
• Application Number:
  US10/845,503
• Publication Number:
  US 20040227580A1
• Time in Patent Office: 865 Days
• Field of Search: 326/30, 326/101, 333/4, 333/5, 333/33, 174/74.R
• US Class Current: 326/86
• CPC Class Codes: H01L 2224/45015 being circular
• CPC Class Codes: H01L 2224/45028 Side-to-side arrangements
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/45565 Single coating layer
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/13091 Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/30107 Inductance
• CPC Class Codes: H01L 2924/3011 Impedance
• CPC Class Codes: H01L 2924/30111 matching
• CPC Class Codes: H01P 3/02 with two longitudinal conductors

Abstract

A differential signal transmission cable structure for transmitting differential signals having GHz frequency band in the present invention is provided with a differential signal transmission pair cable 30 connecting a driver circuit 23a and a receiver circuit 23b, for transmitting differential signals having GHz frequency band, and a power supply ground transmission pair cable 31 connecting ground and a first power supply 26a connected to the driver circuit and ground and a second power supply 26b connected to the receiver circuit. Further characteristic impedance of the differential signal transmission pair cable is matched to that of the driver circuit and the receiver circuit, thereby enabling TEM waves of differential signals having GHz frequency band transmission mode to be maintained when the differential signals are transmitted.

Claims

1. A differential signal transmission cable structure for transmitting differential signals having a GHz frequency band, comprising:

a differential signal transmission pair cable connecting a driver circuit and a receiver circuit that transmits the differential signals having a GHz frequency band while matching characteristic impedances of the driver circuit and the receiver circuit; and

a power supply ground transmission pair cable connecting a first power supply and ground connected to the driver circuit and a second power supply and ground connected to the receiver circuit that matches characteristic impedances of the first power supply and ground and the second power supply and ground;

wherein, as matching characteristic impedances of the power supply ground transmission cable and the differential signal transmission cable, TEM waves of the differential signals having a GHz frequency band are maintained when the differential signal transmission cable transmits the transmission signals having a GHz frequency band.

2. A differential signal transmission cable structure according to claim 1, further comprising:

a relay circuit having a driver circuit and a receiver circuit for inputting and outputting differential signals having a GHz frequency band, disposed on the differential signal transmission pair cable,

wherein the relay circuit, disposed on the power supply ground transmission pair cable, inputs and outputs components of variation from power supply and ground arising due to fluctuations of the differential signals having a GHz frequency band.

3. A differential signal transmission cable structure according to claim 1, wherein the differential signal transmission pair cable comprises:

a pair of wires that have core wires of conducting material that are covered with a first insulating material; and

a covering that covers the pair of wires comprising a second insulating material having a relative permittivity of 1 to 1.3 times greater than the relative permittivity of the first insulating material.

4. A differential signal transmission cable structure according to claim 3, wherein the differential signal transmission pair cable comprises four pair cables, and the four pair cables are arranged flatly such that each of the center lines joining the centers of the pair of wires comprising each pair cable are parallel with respect to each other.

5. A differential signal transmission cable structure according to claim 3, wherein the differential signal transmission pair cable comprises four pair cables, and the four pair cables are arranged such that each two adjoining center lines joining the centers of the pair of wires comprising each pair cable intersect at an angle π

/2 (rad).

13. A differential signal transmission cable structure according to claim 1, wherein the differential signal transmission pair cable is a pair coplanar cable comprising two pair cables having two wires arranged parallel with a first interval, the two pair cables being arranged such that these four wires follow above the same straight line and the center two wires among the four wires are arranged with a second interval.

14. A differential signal transmission cable structure according to claim 1, wherein the differential signal transmission pair cable is a stacked pair cable comprising two pair cables having two wires arranged parallel with a first interval, the two pair cables being arranged such that the center lines joining the centers of the two wires forming each the pair cable are parallel with respect to each other, and the two pair cables are arranged with a second interval.

15. A differential signal transmission cable structure according to claim 1, wherein the differential signal transmission pair cable is a guard coplanar cable comprising two cables having a single wire and two other wires arranged parallel such that said single wire is disposed therebetween, said two other wires being connected in common, the two cables being arranged such that said six wires follow along the same straight line, the two center wires among said six wires being arranged with a prescribed interval.

16. A differential signal transmission cable structure according to claim 1, wherein the differential signal transmission pair cable is a guard stacked pair cable comprising two cables having a single wire and two other wires arranged parallel such that the single wire is disposed therebetween, said two cables being arranged such that the center lines joining the centers of the wires forming the cables are parallel with respect to each other, the pair cables being arranged with a prescribed interval.

6. A differential signal transmission cable structure for transmitting differential signals having a GHz frequency band, comprising:

a differential signal transmission pair cable connecting a driver circuit and a receiver circuit; and

a directionality coupler for transmitting differential signals having a GHz frequency band;

wherein said coupler comprises;

first parallel electrodes disposed at an end of the driver circuit;

long shaped flat plates and second parallel electrodes disposed at an end of the differential signal transmission pair cable; and

long shaped flat plates arranged in proximity to the first parallel electrodes.

8. A differential signal transmission cable structure according to claim 6, wherein, when differential signals output from said driver circuit are input respectively into one end of a resistance R_F and a condenser C_F that are connected in parallel, the other end of the resistance R_F and the condenser C_F are input to a twisted pair cable, the other ends of the twisted pair cable are connected to a terminating resistance R_T and both ends of the terminating resistance R_T are connected to receiver terminals of a receiver circuit;

and

total stray capacitance C_ST arising in the region surrounding said terminating resistance R_T, satisfies R_T/(R_F+R_T)=α

C_F/(C_ST+C_F), where α

=0.7 to 1.3.

10. A differential signal transmission cable structure according to claim 6, wherein the directionality coupler has a quartz layer accommodating the first parallel electrodes and an air layer accommodating the second parallel electrodes.

11. A differential signal transmission cable structure according to claim 6, wherein the directionality coupler has a first insulating layer of quartz accommodating the first parallel electrodes and a second insulating layer of aluminum accommodating the second parallel electrodes.

7. A differential signal transmission cable structure for transmitting differential signals having a GHz frequency band, comprising:

a differential signal transmission pair cable connecting a driver circuit and a receiver circuit, and

a capacitance coupler for transmitting differential signals having a GHz frequency band;

wherein said coupler comprises;

first parallel electrodes disposed at an end of the driver circuit;

long shaped flat plates and second parallel electrodes disposed at an end of the differential signal transmission pair cable; and

long shaped flat plates arranged in proximity to the first parallel electrodes.

9. A differential signal transmission cable structure according to claim 7, wherein, when differential signals output from said driver circuit are input respectively into one end of a resistance R_F and a condenser C_F that are connected in parallel, the other end of the resistance R_F and the condenser C_F are input to a twisted pair cable, the other ends of the twisted pair cable are connected to a terminating resistance R_T and both ends of the terminating resistance R_T are connected to receiver terminals of a receiver circuit;

and

total stray capacitance C_ST arising in the region surrounding said terminating resistance R_T, satisfies R_T/(R_F+R_T)=α

C_F/(C_ST+C_F), where α

=0.7 to 1.3.

12. A differential signal transmission cable structure according to claim 7, wherein the capacitance coupler is comprised of chip capacitors.

17. A differential signal transmission cable structure for transmitting differential signals having GHz frequency band, comprising:

a first stacked pair cable connected to a pair of gate terminals of a pair of transistor elements comprising a differential circuit,

a coplanar cable connected to a pair of drain terminals of the pair of transistor elements, for inputting power supplied via resistance, and

a second stacked pair cable connected to the pair of drain terminals of said pair of transistor elements, for outputting external differential signals.

18. A differential signal transmission cable structure according to claim 17, wherein the first stacked pair cable or the second pair cable comprises a transmission cable disposed within insulating layers vertically for a flat ground layer.

19. A differential signal transmission cable structure comprising:

a differential signal transmission pair cable connecting a driver circuit and a receiver circuit; and

a power supply ground transmission pair cable connecting a first power supply and ground connected to the driver circuit and a second power supply and ground connected to the receiver circuit that matches characteristic impedances of the first power supply and ground and the second power supply and ground;

wherein TEM waves of the differential signals having a GHz frequency band are maintained when the differential signal transmission cable transmits the transmission signals having a GHz frequency band.

20. A differential signal transmission cable structure comprising:

a differential signal transmission pair cable connecting a driver circuit and a receiver circuit; and

a directionality coupler for transmitting differential signals having a GHz frequency band;

wherein said coupler further comprises;

first parallel electrodes disposed at an end of the driver circuit;

long shaped flat plates and second parallel electrodes disposed at an end of the differential signal transmission pair cable; and

long shaped flat plates arranged in proximity to the first parallel electrodes.