Radiation-hard precision voltage reference

Patent metadata

Field	Value
Publication number	US-10566974-B2
Application number	US-201916267861-A
Country	US
Kind code	B2
Filing date	Feb 5, 2019
Priority date	Jun 30, 2015
Publication date	Feb 18, 2020
Grant date	Feb 18, 2020

Abstract

Provided is a Precision Voltage Reference (PVR). In one example, the PVR includes a resonator having an oscillation frequency, the resonator including a first proof-mass, a first forcer located adjacent a first side of the first proof-mass, and a second forcer located adjacent a second side of the first proof-mass. The PVR may include control circuitry configured to generate a reference voltage based on the oscillation frequency of the resonator, at least one converter configured to receive the reference voltage from the control circuitry, provide a first bias voltage to the first forcer based on the reference voltage, provide a second bias voltage to the second forcer based on the reference voltage, and periodically alter a polarity of the first and second bias voltages to drive the oscillation frequency to match a reference frequency, and an output configured to provide the reference voltage as a voltage reference signal.

First claim

What is claimed is:

1. A Precision Voltage Reference (PVR) comprising:
a resonator having an oscillation frequency, the resonator including a first proof-mass, a first forcer located adjacent a first side of the first proof-mass, and a second forcer located adjacent a second side of the first proof-mass;
control circuitry configured to generate a reference voltage based on the oscillation frequency of the resonator;
at least one converter coupled to the control circuitry, the first forcer, and the second forcer, the at least one converter configured to receive the reference voltage from the control circuitry, provide a first bias voltage to the first forcer based on the reference voltage, provide a second bias voltage to the second forcer based on the reference voltage, and periodically alter a polarity of the first bias voltage and the second bias voltage to drive the oscillation frequency of the resonator to match a reference frequency; and
an output configured to provide the reference voltage as a voltage reference signal,
wherein the control circuitry includes a frequency module coupled to the at least one converter, and the frequency module comprises:
a frequency detector configured to detect the oscillation frequency of the resonator;
a frequency comparator configured to compare a time-average of the oscillation frequency to the reference frequency; and
a frequency controller configured to generate a force adjustment signal based on the compared oscillation frequency and reference frequency to adjust the reference voltage generated by the control circuitry such that the oscillation frequency of the resonator matches the reference frequency.

2. The PVR according to claim 1 , wherein in periodically altering the polarity of the first bias voltage and the second bias voltage, the at least one converter is further configured to drive the first bias voltage and the second bias voltage between the reference voltage and a ground reference.

3. The PVR according to claim 2 , further comprising a voltage reference coupled to the proof-mass and configured to reference the proof-mass to substantially one half of the reference voltage.

4. The PVR according to claim 1 , wherein the control circuitry includes an amplitude module coupled to the first forcer and the second forcer, wherein the amplitude module comprises:
an amplitude detector configured to detect an oscillation amplitude of resonator oscillations;
an amplitude comparator configured to compare the oscillation amplitude to an amplitude reference; and
an amplitude controller configured to generate an amplitude adjustment signal based on the compared oscillation amplitude and amplitude reference.

5. The PVR according to claim 4 , further comprising:
a first tunable capacitor coupled to the first forcer;
a second tunable capacitor coupled to the second forcer; and
an amplifier coupled to the first tunable capacitor, the second tunable capacitor, and the amplitude module, wherein the amplitude adjustment signal controls the amplifier to adjust a differential delay between the first bias voltage provided to the first forcer and the second bias voltage provided to the second forcer.

6. The PVR according to claim 4 , further comprising a bias control circuit coupled to the amplitude module,
wherein the at least one converter includes a first converter coupled to the bias control circuit and the first forcer, and configured to provide the first bias voltage to the first forcer,
wherein the at least one converter includes a second converter coupled to the bias control circuit and the second forcer, and configured to provide the second bias voltage to the second forcer, and
wherein the amplitude adjustment signal controls the bias control circuit to adjust a differential delay between the first bias voltage provided to the first forcer and the second bias voltage provided to the second forcer.

7. The PVR according to claim 1 , wherein the at least one converter includes a one-bit digital-analog converter.

8. The PVR according to claim 1 , wherein the resonator further includes:
a second proof-mass;
a third forcer located adjacent a first side of the second proof-mass; and
a fourth forcer located adjacent a second side of the second proof-mass,
wherein, the at least one converter is configured to apply at least one of the first bias voltage and the second bias voltage to at least one of the third forcer and the fourth forcer.

9. A Precision Voltage Reference (PVR) comprising:
a resonator having an oscillation frequency, the resonator including a first proof-mass, a first forcer located adjacent a first side of the first proof-mass, and a second forcer located adjacent a second side of the first proof-mass;
control circuitry configured to generate a reference voltage based on the oscillation frequency of the resonator;
conversion means coupled to the first forcer and the second forcer and configured to receive the reference voltage from the control circuitry, provide a first bias voltage to the first forcer based on the reference voltage, provide a second bias voltage to the second forcer based on the reference voltage, and periodically alter a polarity of the first bias voltage and the second bias voltage such that the oscillation frequency of the resonator matches a reference frequency; and
an output configured to provide the reference voltage as a voltage reference signal,
wherein the control circuitry includes means for detecting the oscillation frequency of the resonator, for comparing a time-average of the oscillation frequency to the reference frequency, and for generating a force adjustment signal based on the compared oscillation frequency and reference frequency to adjust the reference voltage generated by the control circuitry such that the oscillation frequency of the resonator matches the reference frequency.

10. A method for generating a precision voltage reference with a resonator having an oscillation frequency, the resonator including a first proof-mass, a first forcer located adjacent a first side of the first proof-mass, and a second forcer located adjacent a second side of the first proof-mass, the method comprising:
receiving a reference voltage with at least one converter coupled to the first forcer and the second forcer;
providing, with the at least one converter, a first bias voltage based on the reference voltage to the first forcer;
providing, with the at least one converter, a second bias voltage based on the reference voltage to the second forcer;
periodically altering a polarity of the first bias voltage applied to the first forcer and the second bias voltage applied to second forcer such that the oscillation frequency of the resonator matches a reference frequency;
providing the reference voltage as a voltage reference signal;
detecting the oscillation frequency of the resonator;
comparing a time-average of the oscillation frequency of the resonator to the reference frequency; and
generating a force adjustment signal responsive to comparing the oscillation frequency of the resonator and the reference frequency, and adjusting, based on the force adjustment signal, the reference voltage such that the oscillation frequency of the resonator matches the reference frequency.

11. The method according to claim 10 , further comprising generating the reference voltage based on an oscillation frequency of the resonator.

12. The method according to claim 11 , wherein periodically altering the polarity of the first bias voltage and the second bias voltage includes driving the first bias voltage and the second bias voltage between the reference voltage and a ground reference.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Ward Paul A
• Pringle James S
• Weinberg Marc Steven
• Harrison Warner G

Classifications

• H10P34/00

  Irradiation with electromagnetic or particle radiation of wafers, substrates or parts of devices · CPC title

• G05F3/04

  wherein the variable is AC · CPC title

• H03L1/02

  against variations of temperature only · CPC title

• H03K19/0033 Primary

  Radiation hardening · CPC title

• G05F3/00

  Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties {(current generators specially designed for use in phase-locked loops H03L7/0891)} · CPC title