Sigma-delta converter and use thereof
View Patent ↗A sigma-delta converter has a signal input for receiving a data word. A clock signal input is designed to supply a clock signal. The sigma-delta converter includes a first clocked-operation accumulator stage whose input side is connected to the signal input, and at least one second clocked-operation accumulator stage connected in series with the first accumulator stage, with its input side coupled to an accumulator output of the first accumulator stage. The sigma-delta converter is configured to process the data word upon each clock signal only in one accumulator stage in the first and the at least one second accumulator stage, and output the processed data word at the accumulator output of the one accumulator stage. As a result, a time-critical response during signal processing is limited just to the accumulator stage which is currently processing the data word.
1. A sigma-delta converter, comprising:
a signal input configured to receive a data word;
a clock signal input configured to receive a clock signal;
a signal output configured to output a modulation signal;
a first clocked-operation accumulator stage comprising an accumulator output, and comprising an accumulator input connected to the signal input; and
at least one second clocked-operation accumulator stage connected in series with the first accumulator stage, comprising an accumulator output and an accumulator input coupled to the accumulator output of the first accumulator stage;
wherein the sigma-delta converter is configured to process the data word upon each clock signal only in one accumulator stage of the first and at least one second accumulator stage, and further configured to output the processed data word at the accumulator output of the one accumulator stage.
2. The sigma-delta converter of claim 1 , further comprising a control circuit configured to effectuate a cyclic actuation of the first and the at least one second accumulator stage, wherein the cyclic actuation cyclically processes the data word such that respectively just one of the first and at least one second accumulator stage is active.
3. The sigma-delta converter of claim 1 , further comprising:
an output stage comprising an input side coupled to the signal output, wherein the output stage is configured to output an output word based on the modulation signal, with the modulation signal indicating an overflow in the first and at least one second accumulator stage.
4. The sigma-delta converter of claim 3 , wherein the output stage comprises a plurality of delay lines comprising series-connected delay elements, where the number of delay lines and the number of series-connected delay elements in at least one delay line correspond to a number of accumulator stages.
5. The sigma-delta converter of claim 4 , wherein the delay elements in the plurality of delay lines have taps between them that collectively form a modulation output of the sigma-delta converter, thereby outputting a modulation word.
6. The sigma-delta converter of claim 5 , wherein the taps are provided at the output of the respective last delay element in each delay line.
7. The sigma-delta converter of claim 5 , wherein the number of taps and the position of the taps in a delay line are obtained from values of the binomial coefficients for an order of the sigma-delta converter.
8. The sigma-delta converter of claim 4 , wherein the delay elements comprise D-type flipflop circuits.
9. The sigma-delta converter of claim 1 , further comprising:
a control circuit comprising an input side connected to the clock signal input, wherein the control circuit is configured to cyclically actuate the first and at least one second accumulator stage for signal processing.
10. The sigma-delta converter of claim 1 , wherein the first and the at least one second clocked-operation accumulator stage respectively comprise a flipflop circuit and an accumulator which comprises a first input, a second input, an overflow output, and a sum output, wherein the sum output is connected to the second input, via the respective one flipflop circuit, and a clock input of the respective one flipflop circuit is coupled to the clock signal input, for the purpose of actuating the flipflop circuit.
11. The sigma-delta converter of claim 10 , wherein the sum output of the accumulator in the first clocked-operation accumulator stage is connected to the first input of the accumulator in the at least one second accumulator stage, and a clock input of the respective one flipflop circuit is coupled to the control unit for the purpose of actuating the flipflop circuit.
12. The sigma-delta converter of claim 10 , wherein a data output of the respective one flipflop circuit in the first accumulator stage is connected to the first input of the accumulator in the at least one second accumulator stage.
13. A sigma-delta converter, comprising:
a signal input configured to receive a data word;
a signal output configured to output a modulation signal;
first accumulation means for processing the data word in clocked fashion;
at least one second accumulation means for processing the data word processed in the first means in clocked fashion;
control means for cyclically actuating the first and the at least one second accumulation means based on a clock signal for carrying out signal processing such that the data word is processed respectively only in one of the first and the at least one second accumulation means for a given clock signal period.
14. The sigma-delta converter of claim 13 , further comprising means for deriving an output word from a modulation signal, the modulation signal indicating an overflow in the first and at least one second accumulation means.
15. The sigma-delta converter of claim 14 , wherein the derivation means comprises a plurality of delay lines comprising series-connected delay elements, wherein a number of delay lines and a number of delay elements in at least one delay line is dependent on a number of the accumulation means.