Measurement input circuit and measurement device

Patent metadata

Field	Value
Publication number	US-11287447-B2
Application number	US-201715632458-A
Country	US
Kind code	B2
Filing date	Jun 26, 2017
Priority date	Jun 26, 2017
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

A measurement input circuit for a measurement device for measuring an electric signal in a device under test comprises a signal input that receives the electronic signal from the device under test and provides the received electronic signal at a signal node, a direct signal coupling path that is coupled between the signal node an electrical ground and comprises a first impedance value, an alternating signal coupling path that is coupled between the signal node and the electrical ground, and comprises a second impedance value that is lower than the first impedance value, and a signal output that is coupled to the signal node and outputs the received electronic signal.

First claim

The invention claimed is:

1. A measurement input circuit for a measurement device for measuring an electric signal in a device under test, the measurement input circuit comprising:
a user interface that receives a selection of a measurement mode according to requirements of a respective measurement task;
a signal input that receives the electronic signal from the device under test and provides the received electronic signal at a signal node,
a direct signal coupling path that is coupled between the signal node and an electrical ground and comprises a first impedance value,
an alternating signal coupling path that is coupled between the signal node and the electrical ground, and comprises a second impedance value that is lower than the first impedance value, and
a signal output that is coupled to the signal node and outputs the received electronic signal,
wherein the direct signal coupling path comprises a first resistor with a first resistance between the signal node and the electrical ground, the first resistor comprises a first tunable resistor and is tunable to at least two first resistance values between 10 kΩ and 100 MΩ; and
wherein the alternating signal coupling path comprises an alternating signal coupling element with a second resistor with a second resistance in series between the signal node and the electrical ground, and the alternating signal coupling element comprises a tunable capacitor that is tunable to at least two capacitance values between 1 μF and 100 nF;
wherein the measurement input circuit comprises a controller that tunes the first resistor, the second resistor and the capacitor according to a selected predetermined measurement mode according to requirements of a respective measurement task received from the user interface,
wherein the predetermined measurement mode according to the respective measurement task is selected based on an operating mode of the device under test,
wherein the alternating signal coupling path comprises a frequency dependent filter and a cutoff frequency of the alternating signal coupling path is set according to the requirements of the respective measurement task.

2. The measurement input circuit according to claim 1 , wherein the first resistor is tunable to a 50 kΩ resistance or a 75 kΩ resistance or a 100 kΩ resistance.

3. The measurement input circuit according to claim 1 , wherein the capacitor is tunable to 1 nF and 2 nF and 5 nF.

4. The measurement input circuit according to claim 1 , wherein the second resistor comprises a second tunable resistor and is tunable to at least two second resistance values between 10 Ω and 100 Ω.

5. The measurement input circuit according to claim 1 , comprising a measurement amplifier, wherein an input port of the measurement amplifier is connected to the signal node.

6. The measurement input circuit according to claim 5 , wherein the measurement amplifier is a broadband amplifier with a bandwidth between 1 GHz and 100 GHz.

7. A measurement device for measuring an electronic signal in a device under test, the measurement device comprising a measurement input circuit, the measurement input circuit comprising:
a user interface that receives a selection of a measurement mode according to requirements of a respective measurement task;
a signal input that receives the electronic signal from the device under test and provides the received electronic signal at a signal node,
a direct signal coupling path that is coupled between the signal node and an electrical ground and comprises a first impedance value,
an alternating signal coupling path that is coupled between the signal node and the electrical ground, and comprises a second impedance value that is lower than the first impedance value, and
a signal output that is coupled to the signal node and outputs the received electronic signal,
wherein the direct signal coupling path comprises a first resistor with a first resistance between the signal node and the electrical ground, the first resistor comprises a first tunable resistor and is tunable to at least two first resistance values; and
wherein the alternating signal coupling path comprises an alternating signal coupling element with a second resistor with a second resistance in series between the signal node and the electrical ground, and the alternating signal coupling element comprises a tunable capacitor that is tunable to at least two capacitance values between 1 μF and 100 nF;
wherein the measurement input circuit comprises a controller that tunes the first resistor, the second resistor and the capacitor are set according to the received selection of the measurement mode received from the user interface, and
wherein the alternating signal coupling path comprises a frequency dependent filter and a cutoff frequency of the alternating signal coupling path is set according to the requirements of the respective measurement task.

8. The measurement device according to claim 7 , wherein the first resistor is tunable to resistance values between 10 kΩ and 100 MΩ.

9. The measurement device according to claim 7 , wherein the capacitor is tunable to 1 nF and 2 nF and 5 nF.

10. The measurement device according to claim 7 , wherein the second resistor comprises a second tunable resistor and is tunable to at least two first resistance values, especially resistance values between 10 Ω and 100 Ω.

11. The measurement device according to claim 7 , comprising a measurement amplifier, wherein an input port of the measurement amplifier is connected to the signal node.

12. The measurement device according to claim 11 , wherein the measurement amplifier is a broadband amplifier with a bandwidth between 1 GHz and 100 GHz.

Assignees

• Rohde & Schwarz

Inventors

• Peschke Martin

Classifications

• G01R1/06766 Primary

  Input circuits therefor · CPC title

• G01R13/0272 Primary

  for sampling · CPC title

• G01R13/22

  Circuits therefor · CPC title

• G01R1/30 Primary

  Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier · CPC title