Differential line driver circuit and method therefor
View Patent ↗A differential line driver circuit comprising a plurality of driver stages is described. Each driver stage is operably coupled to at least one output of the line driver circuit and arranged to receive at least one control signal and to drive at least one output signal on the at least one output of the line driver circuit in accordance with the at least one control signal received thereby. The line driver circuit further comprises at least one delay component arranged to receive the at least one control signal, and to sequentially propagate the at least one control signal to the driver stages with time delays between the propagation of the at least one control signal to sequentially adjacent driver stages. The delay component is arranged to sequentially propagate the at least one control signal to the driver stages such that such that the at least one control signal is propagated with at least one of: a progressively increasing time delay between sequentially adjacent driver stages; and a progressively decreasing time delay between sequentially adjacent driver stages.
1. A differential line driver circuit comprising:
a plurality of driver stages, each driver stage being operably coupled to two different outputs of the line driver circuit and arranged to receive at least one control signal and to drive output signals on the two different outputs of the line driver circuit in accordance with the at least one control signal received thereby;
the line driver circuit further comprises at least one delay component arranged to receive the at least one control signal, and to sequentially propagate the at least one control signal to the driver stages with time delays between the propagation of the at least one control signal to sequentially adjacent driver stages;
wherein
each of the plurality of driver stages includes a first switch, a first resistor, a second switch, and a second resistor,
the first switch of one of the plurality of driver stages is operated with the at least one control signal to couple the first resistor of the one of the plurality of driver stages to one of the different outputs, and
the second switch of the one of the plurality of driver stages is operated with the at least one control signal to couple the second resistor of the one of the plurality of driver stages to another one of the different outputs; and
the delay component is arranged to sequentially propagate the at least one control signal to the driver stages such that the at least one control signal is propagated with at least one of:
a progressively increasing time delay between sequentially adjacent driver stages; and
a progressively decreasing time delay between sequentially adjacent driver stages.
2. The differential line driver circuit of claim 1 , wherein the at least one delay component is arranged to propagate the at least one control signal to the driver stages such that an output signal of the line driver circuit comprises a substantially linear slope.
3. The differential line driver circuit of claim 2 , wherein the at least one delay component is arranged to propagate the at least one control signal to the driver stages such that the at least one control signal is propagated with delays between sequentially adjacent driver stages configured in accordance with a time delay function derived to achieve a constant derivative of an output voltage signal for the switching driver stages.
4. The differential line driver circuit of claim 1 , wherein the at least one delay component is arranged to propagate the at least one control signal to the driver stages such that:
the at least one control signal is propagated with a first set of delays; and
the at least one control signal is propagated with a different set of delays between sequentially adjacent driver stages during a falling slope of at least one of the output signals of the line driver circuit.
5. The differential line driver circuit of claim 4 , wherein the set of delays between sequentially adjacent driver stages during a falling slope of the at least one output signal of the line driver circuit is the reverse of the set of delays between sequentially adjacent driver stages during a rising slope of the at least one of the output signals of the line driver circuit.
6. The differential line driver circuit of claim 4 , wherein different time delays are configured within a respective delay block between adjacent driver stages for a rising slope and a falling slope by configuring different resistances within respective signal paths of an inverter of the delay block.
7. The differential line driver circuit of claim 1 , wherein the line driver circuit comprises a plurality of uniform driver stages.
8. The differential line driver circuit of claim 1 , wherein the line driver circuit comprises a Controller Area Network (CAN) line driver circuit.
9. The differential line driver circuit of claim 1 when implemented within an integrated circuit device comprising at least one die within a single integrated circuit package.
10. The differential line driver circuit of claim 1 , wherein the delay component includes a plurality of delay blocks, and each of the plurality of delay blocks includes a comparator component and an RC circuit operably coupled in series with the comparator component.
11. The differential line driver circuit of claim 1 , further comprising a termination resistor coupled between the different outputs.
12. The differential line driver circuit of claim 1 , wherein the delay component includes a plurality of delay blocks, and each of the plurality of delay blocks includes a pair of series inverters and an RC circuit operably coupled in series with the pair of series inverters.
13. The differential line driver circuit of claim 1 , wherein the delay component includes a plurality of delay blocks, and each of the plurality of delay blocks includes a pair of complimentary transistors.
14. A method of driving output signals for transmission over differential outputs, the method comprising:
receiving at least one control signal; and
sequentially propagating the at least one control signal to a plurality of driver stages with time delays between the propagation of the at least one control signal to sequentially adjacent driver stages, wherein each of the plurality of driver stages includes a first switch, a first resistor, a second switch, and a second resistor,
wherein the method further comprises:
operating the first switch of one of the plurality of driver stages with the at least one control signal to couple the first resistor of the one of the plurality of driver stages to one of the differential outputs;
operating the second switch of the one of the plurality of driver stages with the at least one control signal to couple the second resistor of the one of the plurality of driver stages to another one of the differential outputs;
sequentially propagating the at least one control signal to the driver stages such that:
the at least one control signal is propagated with at least one of:
a progressively increasing time delay between sequentially adjacent driver stages; and
a progressively decreasing time delay between sequentially adjacent driver stages.