Many circuits can be designed as level indicators by using a comparator IC or transistors but these are costly and complex and also time consuming. This circuit removes all the complexity by using a single TA7666p IC. LEDs are used as a power indicator. Different colour LEDs can be used for both the channels. One can also use an LED bargraph display. INPUT signals should be given from preamplifiers. Otherwise, LEDs will not glow at low volumes.
| PARTS LIST | |
| R1-R10 | 1kΩ |
| R11 | 15kΩ |
| R12 | 15kΩ |
| C1 | 0.1µF |
| C2 | 0.1µF |
| C3 | 1µF 16V |
| C4 | 1µF 16V |
| D1-D10 | 10 LEDs |
| IC1 | TA7666P |
If you have mono systems, signals should be given into both the channels. The input is given through two 4.7 µF capacitors and two 18k resistors to pins 1 and 16 respectively.
- Suitable for stereo LED driver
- Wide Supply Voltage Range : VCC = 6V to 12V
- Low Quiscent Current : ICCQ = 4ma (typ.) at Vcc = 9V
- Variable Voltage Gain Because of Inverting Amplifier
- Easy Arrangement for Dual 10 LED’s Driver by Series Connection of TA77666P and TA7667P
مدار ساخت اکولایزر 12 ال ای دی جدید 
ساخت ساعت led