Circuit and method of operating a circuit
View Patent ↗A circuit having a first amplifier with a variable gain, a second amplifier with a variable gain configured to provide an output signal, a control unit, a memory element, and a switching member. The control unit is configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier. The memory element is configured to store a sample of the output signal. The switching member is configured to connect an output port of the circuit to either the second amplifier or to the memory element. A method of operating this circuit is also disclosed.
1. A circuit comprising,
a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal, and
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element, wherein the second amplifier is a digital amplifier.
2. The circuit according to claim 1 ,
wherein the memory element is configured to provide a signal to the output port when the output port is connected to the memory element, and
wherein the signal provided by the memory element is based on the stored sample.
3. The circuit according to claim 1 ,
wherein the memory element is configured to provide a signal to the output port when the output port is connected to the memory element, and
wherein the signal provided by the memory element is identical to the stored sample.
4. The circuit according to claim 1 ,
wherein the memory element is configured to provide a signal to the output port when the output port is connected to the memory element, and
wherein the signal provided by the memory element is an extrapolation of the stored sample.
5. The circuit according to claim 1 ,
wherein the circuit is configured such that the switching member connects the output port to the memory element for a predetermined period of time when the control unit adjusts the variable gain of the first amplifier and the variable gain of the second amplifier.
6. The circuit according to claim 5 ,
wherein the circuit is configured such that the switching member connects the output port to the second amplifier after the predetermined period of time.
7. The circuit according to claim 1 ,
wherein the circuit is configured such that, when the output port is connected to the second amplifier, the output signal of the second amplifier is written into the memory element and the memory element constantly overwrites a previously stored sample in a first-in, first-out manner.
8. The circuit according to claim 1 ,
wherein the circuit is configured such that the memory element is prevented from overwriting the stored sample when the output port is connected to the memory element.
9. The circuit according to claim 1 ,
wherein the control unit is configured to adjust the variable gain of the second amplifier reciprocally proportional and simultaneously to an adjustment of the variable gain of the first amplifier.
10. The circuit according to claim 1 ,
wherein the first amplifier is an analog amplifier.
11. The circuit according to claim 1 ,
further comprising an analog-to-digital converter arranged between the first amplifier and the second amplifier.
12. The circuit according to claim 1 ,
further comprising at least one filter.
13. Method of operating a circuit,
wherein the circuit comprises a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal, and
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element;
the method comprising the steps of:
monitoring a first output signal of the first amplifier,
adjusting the variable gain of the first amplifier and the variable gain of the second amplifier if the first output signal is below a first predefined threshold level or above a second predefined threshold level,
connecting the memory element to the output port for a predetermined period of time if the variable gain of the first amplifier and the variable gain of the second amplifier are adjusted.
14. Method according to claim 13 , further comprising the step of:
connecting the second amplifier to the output port after the predetermined period of time.
15. The circuit according to claim 1 , wherein the first amplifier and the second amplifier are arranged in a main signal path of the circuit.
16. The circuit according to claim 2 , wherein the signal provided by the memory element is identical to the stored sample or an extrapolation of the stored sample.
17. The circuit according to claim 2 ,
wherein the circuit is configured such that the switching member connects the output port to the memory element for a predetermined period of time when the control unit adjusts the variable gain of the first amplifier and the variable gain of the second amplifier.
18. The circuit according to claim 2 ,
wherein the circuit is configured such that, when the output port is connected to the second amplifier, the output signal of the second amplifier is written into the memory element and the memory element constantly overwrites a previously stored sample in a first-in, first-out manner.
19. A circuit comprising,
a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal, and
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element,
wherein the memory element is configured to provide a signal to the output port when the output port is connected to the memory element, and
wherein the signal provided by the memory element is an extrapolation of the stored sample.
20. A circuit comprising,
a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal, and
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element,
wherein the circuit is configured such that the memory element is prevented from overwriting the stored sample when the output port is connected to the memory element.
21. A circuit comprising,
a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal, and
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element,
wherein the control unit is configured to adjust the variable gain of the second amplifier reciprocally proportional and simultaneously to an adjustment of the variable gain of the first amplifier.
22. A circuit comprising,
a first amplifier with a variable gain,
a second amplifier with a variable gain configured to provide an output signal,
a control unit configured to adjust the variable gain of the first amplifier and the variable gain of the second amplifier,
a memory element configured to store a sample of the output signal,
a switching member configured to connect an output port of the circuit either to the second amplifier or to the memory element, and
an analog-to-digital converter arranged between the first amplifier and the second amplifier.