Data transmission circuits and data transceiver systems
A transmission circuit includes a serial clock generator, a serializer and a transmission clock generator. The serial clock generator generates a serial clock. The serializer serializes N-bit parallel data to N-bit serial data in synchronization with the serial clock. The transmission clock generator receives the serial clock to generate a transmission clock that has a same delay as the N-bit serial data, and the data transmission circuit simultaneously transmits the N-bit serial data and the serial clock.
1. A data transmission circuit, comprising:
a serial clock generator configured to generate a serial clock;
a serializer configured to serialize N-bit parallel data to N-bit serial data in synchronization with the serial clock, N being a natural number greater than one; and a transmission clock generator configured to receive the serial clock to generate a transmission clock, the data transmission circuit simultaneously transmitting the N-bit serial data and the transmission clock, wherein the transmission clock generator includes,
a plurality of multiplexers, each of the plurality of multiplexers having a first input terminal that receives a first or second logic value level and a second input terminal that receives a shifted logic value based on the first and second logic value level, the first and second logic value levels alternating among the plurality of multiplexers, and
a plurality of flip-flops, each of the plurality of flip-flops receiving an output from one of the plurality of multiplexers, the plurality of flip-flops configured to receive and delay outputs of the plurality of multiplexers to provide the transmission clock.
2. The data transmission circuit of claim 1 , wherein the serializer and the transmission clock generator have a same circuit configuration.
3. The data transmission circuit of claim 1 , further comprising:
a data buffer configured to receive the N-bit serial data to convert the received N-bit serial data into first and second data signals that have reduced swing levels; and
a clock buffer configured to receive the transmission clock to convert the received the transmission clock into first and second clock signals that have reduced swing levels.
4. The data transmission circuit of claim 3 , wherein the first and second data signals are differential signals.
5. The data transmission circuit of claim 3 , wherein the first and second clock signals are differential signals.
6. The data transmission circuit of claim 1 , wherein the serializer comprises:
a plurality of multiplexers, each of the plurality of multiplexers having a first input terminal that receives a bit of the N-bit parallel data, and a second input terminal that receives a shifted value of a previous bit of the N-bit parallel data; and
a plurality of flip-flops, each of the plurality of flip-flops receiving an output from one of the plurality of multiplexers, the plurality of flip-flops configured to receive and delay outputs of the plurality of multiplexers to provide the N-bit serial data.
7. The data transmission circuit of claim 6 , wherein the serializer provides the N-bit serial data by shifting the N-bit parallel data input by one bit when a first control signal input to the plurality of multiplexers is enabled.
8. The data transmission circuit of claim 1 , wherein the transmission clock generator provides the transmission clock by shifting the first and second logic value levels when a control signal input to the plurality of multiplexers is enabled.
9. The data transmission circuit of claim 8 , wherein the transmission clock has a period that is two times longer than a period of the serial clock.
10. A data transmission and reception system comprising:
the data transmission circuit of claim 1 .
11. The data transmission and reception system of claim 10 , wherein the serializer comprises:
a plurality of multiplexers, each of the plurality of multiplexers having a first input terminal that receives a bit of the N-bit parallel data, and a second input terminal that receives a shifted value of a previous bit of the N-bit parallel data; and
a plurality of flip-flops receiving an output from one of the plurality of multiplexers, the plurality of flip-flops configured to receive and delay outputs of the plurality of multiplexers to provide the N-bit serial data.
12. The data transmission and reception system of claim 10 further comprising:
a deserializer configured to receive the N-bit serial data and the second clock to deserialize the N-bit serial data to the N-bit parallel data in synchronization with the first clock, the N-bit serial data and the second clock being simultaneously transmitted.
13. The data transmission and reception system of claim 12 , wherein the deserializer is configured to deserailize the N-bit serial data to the N-bit parallel data by having a symmetric circuit configuration with respect to the serializer.
14. The data transmission and reception system of claim 12 , wherein the serializer comprises:
a plurality of multiplexers, each of the plurality of multiplexers having a first input terminal that receives a bit of the N-bit parallel data, and a second input terminal that receives a shifted value of a previous bit of the N-bit parallel data; and
a plurality of flip-flops receiving an output from on of the plurality of multiplexers, the plurality of flip-flops configured to receive and delay outputs of the plurality of multiplexers to provide the N-bit serial data.