Datasheetoo: DATASHEET and Circuit Diagram

The TDA5140A device is a bipolar integrated circuit which commonly used to draw 3-phase brushless DC motors in full-wave mode. This Brushless DC motor drive device is sensorless using the back-EMF sensing technique to sense the rotor position. This device used to be apply in applications such as VCR, laser beam printer, fax machine, blower, automotive. [...]

This circuit below is part of a microprocessor-based digital tachometer and hourmeter with a built-in overspeed switch which is accurate to measure speed and running hours. It is MTH6 digital tachometer and hourmeter and is equipped with easy calibration feature. This kind of device can be used in applications such as generators, compressors, marine engines, oil field equipment and etc. [...]

The laser driver circuit diagram shows the schematic of an IC-NZN application, an all-purpose laser driver circuit. It operates from 3.3 to 5.5 V and can drive N, M, and P-type laser diodes with or without monitor diode. The latest generation of all-purpose integrated laser driver solutions supports switching frequencies up to 155 MHz and laser currents up to 300 mA. [...]

The phase shift oscillator works in such a way that if the amplitude of the inverting amplifier is not high enough the system will continually attenuate the signal until the amplitude is zero, it was therefore decided to change the amplification power of the inverting amplifier. [...]

And here is the NCP1034 datasheet(source:onsemi.com). [...]