Patent Application
20250141554
This disclosure relates to an optical transceiver, more particularly to an optical transceiver equipped with filtering capacitors having noise absorber.
Fiber optics are widely used for transmitting audio and data signals. As a transmission medium, optical technology offers numerous advantages over traditional electronic communication methods. For instance, optical signals allow for extremely high transmission rates and very high bandwidth capacity. Additionally, optics also provide more secure signaling since it does not allow partial signals to escape from the optical fiber cables, a situation that can occur in wired systems. Optical transmission can also cover longer distances without signal losses typically associated with copper wires carrying telecommunication signals.
With the increasing speeds of optical transmission offered by electronic modules, additional issues have arisen. For example, electronic devices and components operating at high frequencies often emit signals known as electromagnetic interference (EMI). This form of electrical noise is undesirable as EMI can disrupt the normal operation of other electronic components. Optical transceiver packaging, especially those operating at high transmission speeds, are particularly susceptible to the influence of EMI radiation.
According to one or more embodiment of this disclosure, an optical transceiver includes a printed circuit board, a transceiver module, a plurality of filtering capacitors and a noise absorber. The printed circuit board is provided with a plurality of signal lines and a plurality of gold fingers each connecting one of the plurality of signal lines. The transceiver module is disposed on the printed circuit board and connects the plurality of signal lines. Each of the plurality of filtering capacitors is located on one of the plurality of signal lines. The noise absorber covers at least one surface of the plurality of filtering capacitors opposite to the printed circuit board.
The present disclosure will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and thus are not limitative of the present disclosure and wherein:
In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. According to the description, claims and the drawings disclosed in the specification, one skilled in the art may easily understand the concepts and features of the present disclosure. The following embodiments further illustrate various aspects of the present disclosure, but are not meant to limit the scope of the present disclosure.
Please refer to
The transceiver module 11 may include an optical transmitter and an optical receiver. The transceiver module 11 and the filtering capacitors 12 may be disposed on the printed circuit board 10. The signal lines 102 may also be disposed within the printed circuit board 10. Each of the filtering capacitors 12 are located on one of the signal lines 102. For example, the filtering capacitors 12 may be AC-coupling capacitors or DC-decoupling capacitors. For example, the filtering capacitors 12 may be silicon capacitors and may be suitable for signal speed of the signal lines 102 ranging from 56 to 112 GBaud rates. The filtering capacitors 12 when placed on the signal lines 102 may have low broadband insertion loss, helping achieve energy consumption reduction. Further, the filtering capacitors 12 may be packaged in smaller cases to reduce the overall size of the optical transceiver 1 and even corresponding parasitic capacitance. Further, the filtering capacitors 12 may be of high capacitance.
Each of the signal lines 102 may connect one of the gold fingers 101 and the transceiver module 11. For example, the signal line 102 may connect the transceiver module 11 to a filtering capacitor 12 and further connect said filtering capacitor 12 to a corresponding gold finger 101.
It should be noted that in addition to the transceiver module 11 and the filtering capacitors 12, the optical transceiver 1 may include other electronic element(s) disposed on the printed circuit board 10. Further,
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With the noise absorber 13, the electromagnetic interference (EMI) on the optical transceiver 1 may be reduced, thereby lowering the impact of electromagnetic interference on the operation of the optical transceiver.
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Materials of the noise absorber 13 may include nickel, silicone and iron, with the nickel being 37% to 42% in terms of percent by weight, the silicone being 15% to 25% in terms of percent by weight, and the iron being 38% to 43% in terms of percent by weight.
Please refer to table 1 below, which shows the testing result of EMI leakage on the optical transceiver of using general noise absorber (condition 1) and the optical transceiver using the noise absorber as described above (condition 2). Specifically, for condition 2, the optical transceiver has the structure as shown in
In table 1, the testing parameters of carrier frequency, field strength level, field strength limit and test distance are shown. The margin of the average type of condition 2 is higher than that of condition 1 by 4.46, which shows that condition 2 has improvement in reducing EMI.
In addition, one of the filtering capacitors 12 may be in 01005 inch size (meaning 0.4 mm×0.2 mm×0.2 mm in size), and the rest of the filtering capacitors 12 may be in 0402 inch size (meaning 0.6 mm×0.3 mm×0.23 mm in size); or, each of the filtering capacitors 12 may be in 01005 inch size. Accordingly, by reducing the size of one or more of the filtering capacitors 12, energy of EMI radiation leakage may be reduced.
Please refer to table 2 below, which shows the testing result of EMI leakage on the optical transceiver of using the filter capacitors in 0402 inch size (condition 1) and the optical transceiver of using the filter capacitors in 01005 inch size (condition 2). Specifically, for condition 2, the optical transceiver has the structure as shown in
In table 2, the testing parameters of carrier frequency, field strength level, field strength limit and test distance are shown. The margin of the average type of condition 2 is higher than that of condition 1 by 1.96, which shows that condition 2 has improvement in reducing EMI.
In view of the above description, electromagnetic interference (EMI) on the optical transceiver according to one or more embodiments of the present disclosure may be reduced, thereby lowering the impact of electromagnetic interference on the operation of the optical transceiver.
The embodiments are chosen and described in order to best explain the principles of the present disclosure and its practical applications, to thereby enable others skilled in the art to best utilize the present disclosure and various embodiments with various modifications as are suited to the particular use being contemplated. It is intended that the scope of the present disclosure is defined by the following claims and their equivalents.
