HIGH SPEED, HIGH EFFICIENCY, HIGH POWER RF PULSE MODULATING INTEGRATED SWITCH

• US 20150130657A1
• Filed: 11/08/2013
• Published: 05/14/2015
• Est. Priority Date: 11/08/2013
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Young, Richard D., Stading, Mark E., Saunders, Jeffrey H., Richardson, Mark T., Kultran, Denpol, Gerace, George W.
• Granted Patent: US 9,287,870 B2
• Time in Patent Office: Days
• US Class Current: 342/175
• CPC Class Codes: G01S 13/02 Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
• CPC Class Codes: G01S 7/02 of systems according to group G01S13/00
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: H03K 19/0013 in field effect transistor circuits
• CPC Class Codes: H03K 19/01721 by means of a pull-up or down element

Abstract

Embodiments of a drain modulator that uses high power switch sensing to control active pulldown are generally described herein. In some embodiments, a logic and sense module is arranged to receive a control signal for controlling an on and an off state of an input of a switch to turn a high power voltage at an output of the switch on and off. A pullup module and a pulldown module are coupled to the input of the switch. An active pulldown module coupled to the output of the switch. The logic and sense module monitors the input to the switch and activates the active pulldown module to drain the output of the switch to a zero voltage when the input of the switch transitions to the off state.

Claims

1. A drain modulator, comprising:

a logic and sense module arranged to receive a control signal for controlling an on and an off state of an input of a switch to turn a high power voltage at an output of the switch on and off;

a pullup module coupled to the input of the switch;

a pulldown module coupled to the input of the switch; and

an active pulldown module coupled to the output of the switch;

wherein the logic and sense module monitors the input to the switch and activates the active pulldown module to drain the output of the switch to a zero voltage when the input of the switch transitions to the off state.

2. The drain modulator of claim 1, wherein the switch is a high power field effect transistor (FET).

3. The drain modulator of claim 2, wherein the logic and sense module mirrors a threshold of a gate of the FET to track switch timing independent of process conditions and temperature.

4. The drain modulator of claim 2, wherein the logic and sense module includes a gate sense module to detect an edge of the voltage at the input to the FET and provides an indication of the detected edge of the voltage at the input of the FET to a gate sense drive module.

5. The drain modulator of claim 4, wherein the logic and sense module includes an active pulldown trigger arranged to activate the active pulldown module to cause the active pulldown module to drain current from the FET thereby causing the voltage at a drain of the FET to go to zero volts.

6. The drain modulator of claim 1, wherein the pullup module is pulsed by the logic and sense module to create an off state at the input of the switch.

7. The drain modulator of claim 1, wherein the pulldown is pulsed by the logic and sense module to create an on state at the input of the switch.

8. The drain modulator of claim 1, wherein the logic and sense module includes digital logic for processing the control signal to generate a pulse to the pullup module and the pulldown module.

9. The drain modulator of claim 1, wherein the logic and sense module provides a high current pulse mode for fast switch rise and fall times with a low current sustain mode to reduce power consumption when the switch is in steady state.

10. A method for providing gate sensed active pulldown to a high power switch, comprising:

receiving, at a control module, a control signal for controlling an output voltage of a high power switch, the control signal communicating an on state and an off state for the high power switch;

generating, by the control module, a first input state at an input to the high power switch to turn on the high power switch in response to the control signal communicating an on state for the high power switch;

generating, by the control module, a second input state at an input to the high power switch to turn off the high power switch in response to the control signal communicating an off state for the high power switch;

monitoring the input to the high power switch to determine whether the input to the high power switch is in the first input state or the second input state; and

pulling down the output voltage of the high power switch to zero volts by an active pulldown module when the input to the high power switch is determined to transition to the second input state.

11. The method of claim 10, wherein the receiving a control signal for controlling an output voltage of a high power switch further comprises receiving a control signal for controlling an output voltage of a field effect transistor (FET).

12. The method of claim 11, wherein the monitoring the input to the high power switch further comprises mirroring a threshold of a gate of the FET to track switch timing independent of process conditions and temperature.

13. The method of claim 11, wherein the monitoring the input to the high power switch further comprises detecting detect an edge of the voltage at the input to the FET and providing an indication of the detected edge of the voltage at the input of the FET to a gate sense drive module.

14. The method of claim 11, wherein the pulling down the output voltage of the high power switch to zero volts further comprises activating the active pulldown module to cause the active pulldown module to drain current from the FET thereby causing the voltage at a drain of the FET to decrease to zero volts.

15. The method of claim 10, wherein the pulling down the output voltage of the high power switch to zero volts further comprises pulsing a pullup module to create an off state at the input of the switch.

16. The method of claim 10, wherein the pulling down the output voltage of the high power switch to zero volts further comprises pulsing the pulldown module to create an on state at the input of the switch.

17. The method of claim 10, wherein the pulling down the output voltage of the high power switch to zero volts further comprises providing a high current pulse mode for fast switch rise and fall times with a low current sustain mode to reduce power consumption when the switch is in steady state.

18. A radar system, comprising:

a waveform generator for generating radar waveforms;

a high power amplifier, arranged to receive the generated waveforms and to amplify the generated waveforms to produce a high power radar transmission signal;

a drain modulator, coupled to the high power amplifier, the drain modulator arranged to switch the high power amplifier on and off, wherein the drain modulator includes;

a logic and sense module arranged to receive a control signal for controlling an on and an off state of an input of a switch to turn a high power voltage at an output of the switch on and off for turning the high power amplifier on and off;

a pullup module coupled to the input of the switch;

a pulldown module coupled to the input of the switch; and

an active pulldown module coupled to the output of the switch;

wherein the logic and sense module monitors the input to the switch and activates the active pulldown module to drain the output of the switch to a zero voltage when the input of the switch transitions to the off state.

19. The radar system of claim 18, wherein the switch is a high power field effect transistor (FET).

20. The radar system of claim 19, wherein the logic and sense module mirrors a threshold of a gate of the FET to track switch timing independent of process conditions and temperature.

21. The radar system of claim 19, wherein the logic and sense module includes a gate sense module to detect an edge of the voltage at the input to the FET and provides an indication of the detected edge of the voltage at the input of the FET to a gate sense drive module.

22. The radar system of claim 21, wherein the logic and sense module includes an active pulldown trigger arranged to activate the active pulldown module to cause the active pulldown module to drain current from the FET thereby causing the voltage at a drain of the FET to go to zero volts.

23. The radar system of claim 18, wherein the pullup module is pulsed by the logic and sense module to create an off state at the input of the switch.

24. The radar system of claim 18, wherein the pulldown is pulsed by the logic and sense module to create an on state at the input of the switch.

25. The radar system of claim 18, wherein the logic and sense module includes digital logic for processing the control signal to generate a pulse to the pullup module and the pulldown module.