Drift compensation
An embodiment of the present disclosure relates to a device comprising an electronic circuit; an oscillation circuit comprising a quartz crystal, configured to provide a clock signal to the electronic circuit; and a heater configured to increase the temperature of the quartz crystal.
1. A device comprising:
an electronic circuit;
an oscillation circuit comprising a quartz crystal, and configured to provide a clock signal to the electronic circuit;
a heater configured to increase a temperature of the quartz crystal;
an antenna; and
a control circuit configured to:
enable a power amplifier of the electronic circuit; and
after a delay with respect to an instant from which the power amplifier is enabled, enable a passage of signals from the electronic circuit to the antenna.
2. The device of claim 1 , wherein the electronic circuit is a radio frequency transmitter.
3. The device of claim 1 , wherein the control circuit is further configured to control the heater.
4. The device of claim 1 , wherein the heater is dedicated to preheating the quartz crystal.
5. The device of claim 1 , wherein the heater is disposed within 10 mm of the quartz crystal.
6. The device of claim 1 , wherein the heater is a resistor.
7. The device of claim 1 , wherein the control circuit is configured to control a switch to enable the passage of the signals from the electronic circuit to the antenna.
8. The device of claim 1 , further comprising, coupled in series, a first variable capacitor, a first fixed capacitor, the quartz crystal, and a second variable capacitor.
9. The device of claim 8 , further comprising an inverter comprising:
an output terminal coupled between the first variable capacitor and the first fixed capacitor; and
an input terminal coupled between the oscillation circuit and the second variable capacitor.
10. A method of controlling a device comprising an electronic circuit, the method comprising:
preheating, with a heater, a quartz crystal of an oscillation circuit providing a clock signal to the electronic circuit; and
enabling an emission of signals as a temperature of the quartz crystal decreases, the enabling comprising:
enabling a power amplifier of the electronic circuit; and
after a delay with respect to an instant from which the power amplifier is enabled, enabling a passage of signals from the electronic circuit to an antenna.
11. The method of claim 10 , wherein the heater comprises a resistor, and the preheating comprises increasing a current going through the resistor.
12. The method of claim 10 , further comprising controlling capacitances of first and second variable capacitors coupled in series with the quartz crystal to be above 50% of maximum capacitances of the first and second variable capacitors, respectively.
13. The method of claim 10 , wherein the heater is dedicated to preheating the quartz crystal.
14. The method of claim 10 , wherein the preheating comprises starting the heater and then stopping the heater prior to the enabling the emission of the signals.
15. The method of claim 14 , further comprising leaving the heater stopped during the enabling the emission of the signals.
16. A method of controlling a device comprising an electronic circuit, the method comprising:
preheating, with a heater, a quartz crystal of an oscillation circuit providing a clock signal to the electronic circuit;
enabling an emission of signals as a temperature of the quartz crystal decreases; and
controlling capacitances of first and second variable capacitors coupled in series with the quartz crystal to be above 50% of maximum capacitances of the first and second variable capacitors, respectively.
17. The method of claim 16 , wherein the heater comprises a resistor, and the preheating comprises increasing a current going through the resistor.
18. The method of claim 16 , wherein the heater is dedicated to preheating the quartz crystal.
19. The method of claim 16 , wherein the preheating comprises starting the heater and then stopping the heater prior to the enabling the emission of the signals.
20. The method of claim 19 , further comprising leaving the heater stopped during the enabling the emission of the signals.