Abstract: A piezoelectric oscillator unit maintains the adhesive force of a quartz vibrator package with respect to a circuit substrate even when the solder connecting the quartz vibrator package to the circuit substrate melts. This prevents the vibrator package from lifting from or falling off of the circuit substrate. In this piezoelectric oscillator unit, a quartz vibrator housing a quartz member is overlaid on a box-shaped circuit substrate on which an oscillating circuit, a temperature compensation circuit, or other circuits are mounted. The electrodes provided on the four corners of the top surface of the circuit substrate and the electrodes provided on the four corners of the bottom surface of the quartz vibrator are bonded together using solder, and also the circuit substrate and the quartz vibrator are mechanically coupled by an adhesive.

Abstract: A quartz oscillator is constructed to achieve a better yield when being mass-produced, by providing a margin of strength for each of the substrates thereof while reducing the thickness of the quartz oscillator devices. A box-shaped circuit substrate is provided for mounting thereon circuit components having different heights from one another. The bottom plate of a recess in this circuit substrate has a level difference, and is constituted of a region where the thickness of the bottom plate is relatively larger and a region where the thickness of the bottom plate is relatively smaller. High-profile circuit components are mounted on the region where the thickness of the bottom plate is smaller, while low-profile components are mounted on the region where the thickness of the bottom plate is larger. By thus increasing the thickness of one portion of the bottom plate of the circuit substrate, the bending strength of the circuit substrate is improved.

Abstract: A compact quartz oscillator includes a quartz vibrator that is integrally mounted on a circuit substrate. In the quartz oscillator, flux residue can be easily washed away. A cavity is defined in the approximate center of the circuit substrate. Within the cavity, circuit components defining an oscillation circuit, a temperature-compensating circuit, and other such circuits are surface-mounted preferably via reflow soldering. Connection electrodes are disposed at the four corners of walls surrounding the cavity. The connection electrodes are bonded to electrodes of the quartz vibrator mounted on the circuit substrate preferably via reflow soldering. Recesses are provided in the top surfaces of the walls. With the recesses, clearances are created between the circuit substrate and the quartz vibrator. As a result, in order to wash away flux residue.

Abstract: A piezoelectric oscillator unit maintains the adhesive force of a quartz vibrator package with respect to a circuit substrate even when the solder connecting the quartz vibrator package to the circuit substrate melts. This prevents the vibrator package from lifting from or falling off of the circuit substrate. In this piezoelectric oscillator unit, a quartz vibrator housing a quartz member is overlaid on a box-shaped circuit substrate on which an oscillating circuit, a temperature compensation circuit, or other circuits are mounted. The electrodes provided on the four corners of the top surface of the circuit substrate and the electrodes provided on the four corners of the bottom surface of the quartz vibrator are bonded together using solder, and also the circuit substrate and the quartz vibrator are mechanically coupled by an adhesive.

Abstract: A compact quartz oscillator includes a quartz vibrator that is integrally mounted on a circuit substrate. In the quartz oscillator, flux residue can be easily washed away. A cavity is defined in the approximate center of the circuit substrate. Within the cavity, circuit components defining an oscillation circuit, a temperature-compensating circuit, and other such circuits are surface-mounted preferably via reflow soldering. Connection electrodes are disposed at the four corners of walls surrounding the cavity. The connection electrodes are bonded to electrodes of the quartz vibrator mounted on the circuit substrate preferably via reflow soldering. Recesses are provided in the top surfaces of the walls. With the recesses, clearances are created between the circuit substrate and the quartz vibrator. As a result, in order to wash away flux residue.

Abstract: A quartz oscillator is constructed to achieve a better yield when being mass-produced, by providing a margin of strength for each of the substrates thereof while reducing the thickness of the quartz oscillator devices. A box-shaped circuit substrate is provided for mounting thereon circuit components having different heights from one another. The bottom plate of a recess in this circuit substrate has a level difference, and is constituted of a region where the thickness of the bottom plate is relatively larger and a region where the thickness of the bottom plate is relatively smaller. High-profile circuit components are mounted on the region where the thickness of the bottom plate is smaller, while low-profile components are mounted on the region where the thickness of the bottom plate is larger. By thus increasing the thickness of one portion of the bottom plate of the circuit substrate, the bending strength of the circuit substrate is improved.

Abstract: An active filter includes two differential amplifiers. The first amplifier has its inverting input connected to an input terminal of the active filter, its non-inverting input connected to ground through a resistor. A resistor and a capacitor are connected in parallel between the inverting input and output of the first amplifier. The second amplifier has its non-inverting input connected through a resistor to the output of the first differential amplifier and also through a capacitor to ground, its inverting input connected through a resistor to ground and also through a capacitor to its output. A resistor is connected between output of the second amplifier and the inverting input of the first amplifier.