High speed serial link systems

High speed serial link techniques are provided. A system applying the high speed serial link technique comprises a relay unit and an amplifier. The relay unit receives a first pair of differential signals provided by a high speed transmitter of a first device, and provides the amplifier with at least one signal that is generated based on the first pair of differential signals. The amplifier amplifies and converts the signal provided by the relay unit to a second pair of differential signals to be received by a high speed receiver of a second device.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application claims priority of Taiwan Patent Application No. 098122733, filed on Jul. 6, 2009, the entirety of which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to high speed serial link techniques.

2. Description of the Related Art

High speed serial link techniques, such as SATA (serial advanced technology attachment), PCIe (peripheral component interconnect express), USB (universal serial bus) and so on, typically use a pair of differential signals to convey data. Cables adopted in this art typically comprise at least two transmission lines for conveying the pair of differential signals.

However, precise cables are required for high speed differential signal transmission. To ensure transmission reliability, the two transmission lines conveying the pair of differential signals are expected to have identical characteristics, for example, identical lengths or identical transmission abilities.

BRIEF SUMMARY OF THE INVENTION

The invention discloses high speed serial link systems.

An exemplary embodiment of the high speed serial link system comprises a relay unit and an amplifier.

The relay unit receives a first pair of differential signals provided by a high speed transmitter of a first device, and provides the amplifier with at least one signal. The amplifier amplifies and converts the signal, provided by the relay unit, to a second pair of differential signals to be received by a high speed receiver of a second device.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows a block diagram depicting an exemplary embodiment of the high speed serial link technique of the invention.FIG. 1shows a first device102, a second device104, and a high speed serial link106therebetween. The figures of the invention only show the transmission from the first device102to the second device104and not vice versa for simplicity. The transmission, from the second device104to the first device102, may use the same technique as that from the first device102to the second device104.

The first device102comprises a high speed transmitter TX and a control unit108. Under the control of the control unit108, the high speed transmitter TX transmits a first pair of differential signals including a positive signal S1+and a negative signal S1−. The data in the first pair of differential signals S1+and S1−are conveyed to the second device104by the high speed serial link106.

The high speed serial link106comprises a relay unit112and an amplifier114. The relay unit112receives the first pair of differential signals S1+and S1−to provide at least one signal to the amplifier114. The amplifier114amplifies and converts the signal, provided by the relay unit112, to a second pair of differential signals including a positive signal S2+and a negative signal S2−.

The second device104comprises a high speed receiver RX and a control unit110. Under the control of the control unit110, the high speed receiver RX receives the second pair of differential signals S2+and S2−. The control unit110may process the data received by the high speed receiver RX.

FIG. 2depicts another exemplary embodiment of the high speed serial link technique of the invention. Compared withFIG. 1,FIG. 2further discloses a first transmission line line1and a second transmission line line2which separately convey the positive signal S1+and the negative signal S1−of the first pair of differential signals to the relay unit112. The relay unit112electrically couples the first transmission line line1to the amplifier114. Furthermore, the relay unit112comprises a terminating circuit202, which couples the second transmission line line2to ground. The terminating circuit202may be a resistor (for example, a 50 ohm resistor).

InFIG. 2, the amplifier114is realized by a single in differential out amplifier204, which provides an adjustable gain and improves the intensity of the second pair of differential signals (S2+and S2−).

The relay unit112and the amplifier114shown inFIG. 2may form a signal processing device to be assembled on the second device104. In some embodiments, the signal processing device (including the relay unit112and the amplifier114) may be combined with the second device104to form an electronic product or integrated chip.

Furthermore, the first transmission line line1, second transmission line line2, relay unit112and amplifier114may be applied in a high speed serial link cable to accomplish one way transmission thereof.

FIG. 3Adepicts another exemplary embodiment of the high speed serial link technique of the invention. As shown, the relay unit112comprises a transmission line302A and a differential in single out amplifier304. The differential in single out amplifier304A is coupled to the high speed transmitter TX to receive the first pair of the differential signals S1+and S1−and, according to the received signals S1+and S1−, the differential in single out amplifier304A outputs a single end signal to be conveyed to the amplifier114. In this embodiment, the amplifier114is realized by a single in differential out amplifier306A which may have an adjustable gain and can improve the intensity of the second pair of differential signals S2+and S2−.

The differential in single out amplifier304A, the transmission line302A and the single in differential out amplifier306A may be applied in a high speed serial link cable to accomplish one way transmission thereof.

In other exemplary embodiments, the single in differential out amplifier306A is applied to a signal processing device to be assembled on the second device104. The signal processing device (including the single in differential out amplifier306A) may be combined with the second device104as an electronic product or integrated chip. Furthermore, the differential in single out amplifier304A and the transmission line302A may be applied in a high speed serial link cable to convey the first pair differential signals S1+and S1−to the signal processing device comprising the single in differential out amplifier306A.

In other embodiments, the differential in single out amplifier304A may be applied to a first signal processing device to be assembled on the first device102, and the single in differential out amplifier306A may be applied to a second signal processing device to be assembled on the second device104. In this embodiment, the transmission line302A is applied in a high speed serial link cable to link the first and second signal processing devices (realized by the amplifiers304A and306A, respectively). In some embodiments, the first signal processing device (realized by the differential in single out amplifier304A) is combined with the first device102to form an electronic device or integrated chip. The second signal processing device (realized by the single in differential out amplifier306A) may be combined with the second device104to form another electronic device or integrated chip.

FIG. 4shows an exemplary embodiment of the transmission line302A. In this figure, the transmission line302A is realized by a pair of transmission lines line1and line2of a typical high speed serial link cable. As shown, to work as a single transmission line, the input terminals of the transmission lines line1and line2are short together, and the output terminals of the transmission line1and line2are short together.

FIG. 3Bdepicts another exemplary embodiment of the high speed serial link technique of the invention. As shown, the relay unit112is realized by a pair of transmission lines302B and a first differential in differential out amplifier304B. The first differential in differential out amplifier304B is coupled to the high speed transmitter TX to receive the first pair of differential signals S1+and S1−. Based on the first pair of differential signals S1+and S1−, the first differential in differential out amplifier304B generates a pair of relay differential signals to be transmitted to the amplifier114, wherein the pair of relay differential signals is conveyed by the pair of transmission lines302B. The amplifier114may be realized by a second differential in differential out amplifier306B which provides an adjustable gain and improves the intensity of the second pair of differential signals S2+and S2−.

The first differential in differential out amplifier304B and the pair of transmission lines302B and the second differential in differential out amplifier306B ofFIG. 3Bmay be applied in a high speed serial link cable to accomplish one way transmission thereof.

In other embodiments, the second differential in differential out amplifier306B may be applied to a signal processing device to be assembled on the second device104. In some embodiments, the signal processing device (including the second differential in differential out amplifier306B) may be combined with the second device104to form an electronic device or integrated chip. Furthermore, The first differential in differential out amplifier304B and the pair of transmission lines302B may be applied in a high speed serial link cable to convey the first pair of differential signals S1+and S1−from the first device102to the signal processing device realized by the second differential in differential out amplifier306B.

In another embodiment, the first differential in differential out amplifier304B may be applied to a first signal processing device to be assembled in the first device102and the second differential in differential out amplifier306B may be applied to a second signal processing device to be assembled on the second device104, and the pair of transmission lines302B may be part of a high speed serial link cable which couples the first and second signal processing devices (realized by the amplifiers304B and306B, respectively.) The first signal processing device (including the differential in differential out amplifier304B) may be combined with the first device102to form an electronic product or integrated chip. The second signal processing device (including the second differential in differential out amplifier306B) may be combined with the second device104to form another electronic product or integrated chip.

FIG. 5Adepicts another exemplary embodiment of the high speed serial link technique of the invention. The relay unit112is realized by a differential in single out amplifier502A, and the amplifier114is a single in differential out amplifier504A. In this embodiment, a first transmission line line1, a second transmission line line2, a third transmission line line3and a fourth transmission line line4are disclosed. The first and second transmission lines line1and line2convey the first pair of differential signals S1+and S1−, provided by the high speed transmitter TX, to the differential in single out amplifier502A. The third and fourth transmission lines line3and line4convey the second pair of differential signals S2+and S2−, generated by the single in differential out amplifier504A, to the high speed receiver RX of the second device104. The gain of the single in differential out amplifier504A may be adjustable and the single in differential out amplifier504A can improve the intensity of the second pair of differential signals S2+and S2−.

The differential in single out amplifier502A and the single in differential out amplifier504A may form a signal processing device504and may be manufactured into products. The first and second transmission lines line1and line2may be applied in a first high speed serial link cable. The third and fourth transmission lines line3and line4may be applied in a second high speed serial link cable.

In another exemplary embodiment, the first, second, third and fourth transmission lines line1, line2, line3and line4and the differential in single out amplifier502A and the single in differential out amplifier504A may be applied in a high speed serial link cable to accomplish one way transmission thereof.

FIG. 5Bdepicts another exemplary embodiment of the high speed serial link technique of the invention. Compared withFIG. 5A, the differences are the relay unit112and the amplifier114. InFIG. 5B, the relay unit112is realized by a first differential in differential out amplifier502B and the amplifier114is realized by a second differential in differential out amplifier504B. The first and second transmission lines line1and line2convey the first pair of differential signals S1+and S1−, provided by the high speed transmitted TX, to the first differential in differential out amplifier502B. The first differential in differential out amplifier502B converts the first pair of differential signals S1+and S1−to a pair of relay differential signals to be sent to the second differential in differential out amplifier504B. The second differential in differential out amplifier504B converts the pair of relay differential signals to the second pair of differential signals S2+and S2−. The third and fourth transmission lines line3and line4convey the second pair of differential signals S2+and S2−to the high speed receiver RX of the second device104. The gain of the second differential in differential out amplifier504B may be adjustable and the second differential in differential out amplifier504B can improve the intensity of the second pair of differential signals S2+and S2−.

The first and second differential in differential out amplifiers502B and504B ofFIG. 5Bmay form a signal processing device504to be manufactured into products. The first and second transmission lines line1and line2may be applied in a first high speed serial link cable. The third and fourth transmission lines line3and line4may be applied in a second high speed serial link cable.

In another embodiment, the first, second, third and fourth transmission lines line1, line2, line3and line4, and the first and second differential in differential out amplifiers502B and504B ofFIG. 5Bmay be applied in a high speed serial link cable to accomplish one way transmission thereof.

The aforementioned transmission lines may be realized by various techniques. For example, they may be realized by the typical cables for high speed serial link transmissions. Or, they may be realized by electronic wires or PCB traces and so on.