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US 9,712,111 B2Granted
Oscillator, electronic apparatus, and moving object
AssigneeSeiko Epson Corporation
InventorAkihiro Fukuzawa
Life of this patent
Estimating the term…
Abstract
An oscillator includes an input terminal, an oscillation circuit section configured to cause a resonator to resonate to output an oscillator signal, a digital input section to which a signal for controlling an oscillation frequency of the oscillation circuit section is input via the input terminal, and a first bias circuit section including a constant current source configured to supply a reference current to the digital input section.
Claims20
An oscillator comprising:
- an input terminal to which a first digital signal is input, the first digital signal having first and second voltage values, the first voltage value being higher than the second voltage value;
- an oscillation circuit that is configured to output an oscillator signal, an oscillation frequency of the oscillator signal corresponding to the first digital signal;
- a digital input circuit that is configured to receive the first digital signal from the input terminal and that is configured to output a second digital signal, the second digital signal corresponding to the first digital signal, the digital input circuit having a first input circuit and a level shift circuit, the second digital signal having third and fourth voltage values, the third voltage value is lower than the fourth voltage value;
- and
- a first bias circuit that has a constant current source, the constant current source being configured to supply a reference current to the digital input circuit,
- wherein the first input circuit is located at an upstream side of the level shift circuit in the digital input circuit with respect to a signal flow direction of the first digital signal, and
- the first input circuit is configured to receive the first digital signal, the reference current, and a threshold voltage,
- the first input circuit is configured to compare the threshold voltage with one of the first and second voltage values of the first digital signal, and to output a differential signal to the level shift circuit,
- wherein when the one of the first and second voltage values of the first digital signal is higher than the threshold voltage, the level shift circuit is configured to output the second digital signal having the third voltage value based on the differential signal, and
- when the one of the first and second voltage values of the first digital signal is lower than the threshold voltage, the level shift circuit is configured to output the second digital signal having the fourth voltage value based on the differential signal.
7 more elements
Dependencies are inferred from the claim text.