Wideband RF amplifiers

• US 7,944,307 B2
• Filed: 03/19/2009
• Issued: 05/17/2011
• Est. Priority Date: 03/19/2009
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Balboni, Edmund J., Goldfarb, Marc
• Primary Examiner(s): Mottola; Steven J
• Application Number:
  US12/407,148
• Publication Number:
  US 20100237941A1
• Time in Patent Office: 789 Days
• Field of Search: 330/277, 330/290, 330/295
• US Class Current: 330/295
• CPC Class Codes: H03F 1/483 with field-effect transistors
• CPC Class Codes: H03F 2203/45666 the LC comprising two anti-phase controlled inverter circuits as output stages, e.g. fully differential
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence
• CPC Class Codes: H03F 3/45179 using MOSFET transistors as the active amplifying circuit H03F3/45278 takes precedence

Abstract

A device for amplifying signals over a wide frequency range features stacked amplifying modules connected between a DC voltage source and an electrical ground. The stacking configuration reuses the DC current produced the voltage source, and thus reduces the amount of operational DC current permitting the use of lower voltage, higher frequency devices to be used. The amplifying modules are fed signals which are different versions of an input signal, and the output signals are AC coupled using capacitors to balance out gain imbalances and asymmetries between the amplifying modules.

Claims

1. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source; and

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground, wherein the stacked amplifying modules employ DC feedback to establish a stable DC operating point, resulting in the proportional division of the first DC voltage across the stacked amplifying modules.

2. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source;

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground, wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

an input differential amplifier for receiving the input signal and generating multiple signals including the first signal and the second signal, wherein the first signal and the second signal have 180 degree phase difference.

4. The device of claim 2, wherein at least one of the first amplifying module or the second amplifying module comprises an inverter amplifier.

6. The device of claim 4, wherein the inverter amplifier comprises an electrically isolated PMOS transistor and an electrically isolated NMOS transistor.

8. The device of claim 2, wherein the input differential amplifier comprises a bipolar junction transistor (BJT).

9. The device of claim 2, wherein at least one of the first amplifying module or the second amplifying module comprises two-stage cascaded amplifiers.

17. The device of claim 2, wherein the voltage produced by the first DC voltage source is approximately equally divided between the first and second amplifying modules.

18. The device of claim 2, wherein the input signal comprises a radio frequency (RF) signal with a frequency range from about 10 MHz to about 5000 MHz.

3. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source;

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground, wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

a splitter for receiving the input signal and splitting the input signal into multiple signals including the first signal and the second signal, the first signal comprising voltage values of the input signal exceeding a predetermined voltage value, and the second signal comprising voltage values of the input signal falling below the predetermined voltage value.

5. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source; and

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

wherein at least one of the first amplifying module or the second amplifying module comprises an inverter amplifier, wherein the inverter amplifier comprises one or more 0.25 micron transistors.

7. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source; and

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

wherein at least one of the first amplifying module or the second amplifying module comprises an inverter amplifier, wherein the inverter amplifier comprises an electrically isolated transistor, wherein the electrically isolated transistor comprises a deep N-well or triple well transistor.

10. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source;

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

a third amplifying module for amplifying the second signal to produce a third amplified signal, the third amplifying module being directly connected to a second DC voltage source;

a fourth amplifying module for amplifying the first signal to produce a fourth amplified signal, the fourth amplifying module being directly connected to the electrical ground, wherein the third and fourth amplifying modules are stacked between the second DC voltage source and the electrical ground;

a first combiner for combining the first amplified signal and the fourth amplified signal to produce a first output signal; and

a second combiner for combining the second amplified signal and the third amplified signal to produce a second output signal.

11. The device of claim 10, wherein the first combiner comprises a first coupling capacitor.

12. The device of claim 10, wherein the second combiner comprises a second coupling capacitor.

13. The device of claim 10, wherein at least one of the first combiner or the second combiner comprises a transformer, a transmission line, or a multiplicity of inductors, and capacitors.

14. The device of claim 10, wherein at least one of the third amplifying module or the fourth amplifying module comprises two-stage cascaded amplifiers.

16. The device of claim 14, wherein the self-bias circuit comprises a feedback resistor.

27. The device of claim 10:

wherein the first combiner comprises a first coupling capacitor configured to capacitively couple the first amplified signal and the first output signal and a second coupling capacitor configured to capacitively couple the fourth amplified signal and the first output signal;

wherein the second combiner comprises a third coupling capacitor configured to capacitively couple the second amplified signal and the second output signal and a fourth coupling capacitor configured to capacitively couple the third amplified signal and the second output signal.

15. An electronic device for amplifying an input signal, the device comprising:

a first amplifying module for amplifying a first signal to produce a first amplified signal, the first amplifying module being directly connected to a first DC voltage source; and

a second amplifying module for amplifying a second signal to produce a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

wherein at least one of the first amplifying module or the second amplifying module comprises a self-bias circuit.

19. A method of amplifying an input signal, the method comprising:

amplifying a first signal to produce a first amplified signal using a first amplifying module, the first amplifying module being directly connected to a first DC voltage source;

amplifying a second signal to produce a second amplified signal using a second amplifying module, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

receiving the input signal and generating multiple signals including the first signal and the second signal, wherein the first signal and the second signal have 180 degree phase difference.

21. The method of claim 19, wherein at least one of the first amplifying module or the second amplifying module comprises an inverter amplifier.

25. The method of claim 19 further comprising shunting AC voltage from an intermediate node between the stacked first and second amplifying modules via a shunting capacitor.

20. A method of amplifying an input signal, the method comprising:

amplifying a first signal to produce a first amplified signal using a first amplifying module, the first amplifying module being directly connected to a first DC voltage source;

amplifying a second signal to produce a second amplified signal using a second amplifying module, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

splitting the input signal into multiple signals including the first signal and the second signal, the first signal comprising voltage values of the input signal exceeding a predetermined voltage value, and the second signal comprising voltage values of the input signal falling below the predetermined voltage value.

22. A method of amplifying an input signal, the method comprising:

amplifying a first signal to produce a first amplified signal using a first amplifying module, the first amplifying module being directly connected to a first DC voltage source;

amplifying a second signal to produce a second amplified signal using a second amplifying module, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

amplifying the second signal to produce a third amplified signal using a third amplifying module, the third amplifying module being directly connected to a second DC voltage source;

amplifying the first signal to produce a fourth amplified signal using a fourth amplifying module, the fourth amplifying module being directly connected to an electrical ground, wherein the third and fourth amplifying modules are stacked between the second DC voltage source and the electrical ground;

combining the first amplified signal and the fourth amplified signal to produce a first output signal; and

combining the second amplified signal and the third amplified signal to produce a second output signal.

23. A method of amplifying an input signal, the method comprising:

amplifying a first signal to produce a first amplified signal using a first amplifying module, the first amplifying module being directly connected to a first DC voltage source;

amplifying a second signal to produce a second amplified signal using a second amplifying module, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

stabilizing at least one of the first amplifying module or the second amplifying module using a self-bias circuit.

24. The method of claim 23, wherein the self-bias circuit comprises a feedback resistor.

26. A method of amplifying an input signal, the method comprising:

amplifying a first signal to produce a first amplified signal using a first amplifying module, the first amplifying module being directly connected to a first DC voltage source;

amplifying a second signal to produce a second amplified signal using a second amplifying module, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground; and

utilizing DC feedback to establish a stable DC operating point across the stacked amplifying modules, resulting in the proportional division of the first DC voltage across the stacked amplifying modules.

28. An apparatus for amplifying an input signal, the apparatus comprising:

a first amplifying module configured to amplify a first signal to generate a first amplified signal, the first amplifying module being directly connected to a first voltage reference;

a second amplifying module configured to amplify a second signal to generate a second amplified signal, the second amplifying module being directly connected to a second voltage reference, wherein the first and second amplifying modules are stacked between the first voltage reference and the second voltage reference; and

an input differential amplifier configured to receive the input signal and to generate multiple signals including the first signal and the second signal, wherein the first signal and the second signal have 180 degree phase difference.

29. An apparatus for amplifying an input signal, the apparatus comprising:

a first amplifying module configured to amplify a first signal to generate a first amplified signal, the first amplifying module being directly connected to a first DC voltage source;

a second amplifying module configured to amplify a second signal to generate a second amplified signal, the second amplifying module being directly connected to an electrical ground;

wherein the first and second amplifying modules are stacked between the first DC voltage source and the electrical ground;

a third amplifying module configured to amplify the second signal to generate a third amplified signal, the third amplifying module being directly connected to a second DC voltage source;

a fourth amplifying module configured to amplify the first signal to generate a fourth amplified signal, the fourth amplifying module being directly connected to the electrical ground, wherein the third and fourth amplifying modules are stacked between the second DC voltage source and the electrical ground;

a first combiner configured to combine the first amplified signal and the fourth amplified signal to generate a first output signal; and

a second combiner configured to combine the second amplified signal and the third amplified signal to generate a second output signal.

30. The apparatus of claim 29:

wherein the first combiner comprises a first coupling capacitor configured to capacitively couple the first amplified signal and the first output signal and a second coupling capacitor configured to capacitively couple the fourth amplified signal and the first output signal;

wherein the second combiner comprises a third coupling capacitor configured to capacitively couple the second amplified signal and the second output signal and a fourth coupling capacitor configured to capacitively couple the third amplified signal and the second output signal;

wherein the voltage produced by the first DC voltage source is approximately equally divided between the first and second amplifying modules;

wherein at least one of the first amplifying module or the second amplifying module comprises an inverter amplifier, wherein the inverter amplifier comprises an electrically isolated transistor, wherein the electrically isolated transistor comprises an electrically isolated PMOS transistor and an electrically isolated NMOS transistor.