This post explains for the LED Driver.
The Part Number is TA7666P.
The function of this semiconductor is 5 Step Logarithmic Dual LED Driver.
The package is DIP 16 Pin Type
Preview images :
Both of the TA7666P and TA7667P consist of two inverting amplifers, the comparators and a reference voltage netwok. Turn-on level intervals are 5dB, 5dB, 3dB, 3dB, in TA7666P, and are 2dB, 2dB, 2dB, 2dB in TA7667P. It is suitable for stereo radio cassette applications because of dual type.
A 5-step logarithmic dual LED driver is an integrated circuit (IC) that is specifically designed to drive dual LEDs (Light-Emitting Diodes) with a logarithmic brightness control. The logarithmic control allows for smoother and more precise adjustment of the LED brightness across different intensity levels.
The “5-step” in the term refers to the number of distinct brightness levels or steps that can be achieved using the driver. This means that the driver provides five different selectable brightness settings for the LEDs, ranging from low to high intensity.
The driver typically incorporates a logarithmic converter or amplifier that maps the linear control input voltage to a logarithmic scale. This logarithmic mapping allows for a more perceptually uniform adjustment of LED brightness, as the human visual system perceives changes in brightness in a logarithmic manner.
1. Suitable for Stereo LED Driver
2. Variable voltage gain because of inverting amplifier