DS

Overview: AN12942B is an one-chip IC for the stereo speakers which can output 1 W by 8 Ω, headphone amplifiers, line amplifiers, and electronic volumes. The AGC circuit is built-in to prevent the resonance or the vibration by the speaker’s energy and the clipping distortion what is  called "broken up sound".  Also the AN12942B is built-in power saving on/off function automatically detecting input signal to save the power of speaker  amplifier. Circuit Diagram: Audio signal processing

Here is a simple circuit that can be used as a sequential signal light in automobiles. The circuit is based on two ICs. A TS 555 CN CMOS timer IC and a CD4017 decade counter IC. The IC1 is wired as an astable multivibrator to trigger the counter IC. When triggered, the outputs of the IC 2 (pins 3, 2, 4 and 7) will go high and low in sequence and the speed of this sequencing will be proportional to the triggering frequency. The transistors Q1 to Q4 drives the corresponding LEDs. The switch S1 can be used to select the direction of turning and the LEDs arranged at the corresponding side of the vehicle will start sequencing. Notes.    * The switch S1 can be the existing changeover switch of the vehicle it self. * The circuit can be powered of the 12V available from the vehicle itself. * The color of the LED depends on your choice . * The ICs must be mounted on IC holders. * Assemble the circuit on a good quality PCB . * Be careful with the wiring of this circuit  because a...