SEMICONDUCTOR DEVICE AND METHOD OF GENERATING FREQUENCY STABILIZATION FLAG

• Main Author: KOBAYASHI KAUHITO
• Format: Patent
• Language: English; Japanese
• Published: 16.03.2017
• Subjects: BASIC ELECTRONIC CIRCUITRY; CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; ELECTRICITY; GENERATION OF NOISE BY SUCH CIRCUITS; GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING,BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN ANON-SWITCHING MANNER; PHYSICS; PULSE TECHNIQUE

PROBLEM TO BE SOLVED: To generate a proper frequency stabilization flag based on a frequency of an oscillation signal.SOLUTION: A semiconductor device includes: a first circuit that generates a first signal whose level makes a transition depending on transition of a level of an oscillation signal outputted from an oscillation circuit; a second circuit that generates a second signal whose level makes a transition in a case where a time period from when the level of the first signal makes a transition to when the level of the first signal makes a transition next exceeds a predetermined time period; and a third circuit that outputs a third signal that makes a transition to a predetermined level depending on the transition of level of the second signal, and maintains the level of the third signal to the predetermined level.SELECTED DRAWING: Figure 3 【課題】発振信号の周波数に基づく適切な周波数安定フラグを生成する。【解決手段】半導体装置は、発振回路から出力される発振信号のレベルの遷移に応じてレベルが遷移する第１の信号を生成する第１の回路と、第１の信号のレベルが遷移してから第１の信号のレベルが次に遷移するまでの期間が所定期間を超えた場合にレベルが遷移する第２の信号を生成する第２の回路と、第２の信号のレベルの遷移に応じて所定のレベルに遷移する第３の信号を出力し、且つ前記第３の信号のレベルを前記所定のレベルに維持する第３の回路と、を含む。【選択図】図３