Switchable high pass configuration and an optical receiver with a switchable high pass configuration

1. A switchable high-pass filter arrangement configured to determine the high-pass filter behavior of the arrangement by a lower limiting frequency, comprising:

a transistor circuit, comprising at least one transistor in a common-gate or common-base connection, wherein the transistor comprises a control terminal forming an input of the high-pass filter arrangement, and an output terminal forming an output of the high-pass filter arrangement;

a capacitive component in series with an input of the transistor circuit; and

a programmable device comprising a current source connected to the transistor circuit and configured to set an operating current of the transistor circuit by adjusting the current source;

wherein a limiting frequency of the high-pass filter arrangement is switchable by means of the programmable device.

2. The arrangement of claim 1 , wherein the programmable device comprises an additional transistor fed by a switchable voltage source and forms a cascode circuit together with the transistor of the transistor circuit in a common-gate or common-base connection.

3. A switchable high-pass filter arrangement configured to determine the high-pass filter behavior of the arrangement by a lower limiting frequency, comprising:

a transistor circuit, comprising at least one transistor in a common-gate or common-base connection;

a capacitive component in series with an input of the transistor circuit; and

a programmable device configured to set an operating current of the transistor circuit. the programmable device comprising a programmable current mirror;

wherein a limiting frequency of the high-pass filter arrangement is switchable by means of the programmable device.

4. A switchable high-pass filter arrangement configured to determine the high-pass filter behavior of the arrangement by a lower limiting frequency, comprising:

a transistor circuit, comprising at least one transistor in a common-gate or common-base connection;

a capacitive component in series with an input of the transistor circuit; and

a programmable device configured to set an operating current of the transistor circuit, the programmable device comprising a constant-gm circuit configured to generate the operating current that is operable to compensate for temperature influences;

wherein a limiting frequency of the high-pass filter arrangement is switchable by means of the programmable device.

5. The arrangement of claim 4 , wherein the constant-gm circuit comprises switchable resistors that set the operating current of the high pass filter arrangement.

6. The arrangement of claim 1 , wherein the programmable device comprises a means for generating different switching states for selling different operating current magnitudes.

7. The arrangement of claim 1 , wherein the high-pass filter arrangement is coupled to an amplifier circuit.

8. The arrangement of claim 1 , wherein a high-pass filter arrangement is coupled to an output of a differential amplifier circuit.

9. A high-pass filter arrangement, comprising:

a transistor circuit, comprising at least one transistor in a common-gate or common-base connection, wherein the transistor comprises a control terminal forming an input of the high-pass filter arrangement, and an output terminal forming an output of the high-pass filter arrangement;

a capacitive component coupled to the input of the high-pass filter arrangement, wherein the transistor circuit and the capacitive component cooperatively operate to substantially attenuate a signal below a limiting frequency thereof, and provide the attenuated signal at the output, wherein the limiting frequency is a function of transconductance of the transistor circuit and a capacitance of the capacitive component; and

a bias circuit comprising a current source coupled to the transistor circuit, and configured to selectively vary an operating current associated with the transistor circuit by adjusting the current source, thereby altering the transconductance thereof and the limiting frequency of the high-pass filter arrangement.

10. The arrangement of claim 9 , wherein the current source comprises a switchable current source configured to selectively set a plurality of discrete, different operating currents.

11. The arrangement of claim 9 , wherein the bias circuit comprises:

a transistor circuit, and a control terminal; and

a transconductance control circuit configured to generate a control voltage at the control terminal of the transistor, wherein the control voltage is a function of a desired operating current of the transistor circuit.

12. The arrangement of claim 11 , wherein the transistor is configured to generate the desired operating current based on the control voltage coupled thereto.

13. The arrangement of claim 11 , wherein the transconductance of the transistor is kept stable by means of a current mirror and thereby keeping the limiting frequency of the high-pass filter arrangement constant.

14. The arrangement of claim 13 , wherein the current mirror is operable to set a reference current for a reference voltage at the control terminal of the transistor.

15. The arrangement of claim 14 , wherein the transconductance control circuit comprises:

a current mirror circuit; and

a variable reference resistor arrangement, wherein at least two transistors of the current mirror circuit are coupled with negative feedback by resistors of the variable reference resistor arrangement and is switch able by the reference resistor arrangement coupled to control lines and changeover switches.

16. The arrangement of claim 13 , wherein the variable reference resistor arrangement is coupled to control lines and changeover switches, wherein the changeover switches are not situated in the signal path of the high-pass filter arrangement.