VU Meter with UAA180

Description: This circuit of measurement of level uses the UAA180 of SIEMENS and a circuit of rectification of precision, round the IC2B. The calibration has become in steps 3db from the one Led in the other, ensuring, a very good rate of precision, in the measurement of entering acoustic signals. The Led can be square, thus when they are placed the one by in the other, they give the picture of bar, without space.

Part List

R1= 47Kohm R7=2.2K ohm D1....8= LED GREEN
R2= 1Mohm R8-10=330Kohm D9-10= LED YELLOW
R3= 33Kohm R11=180Kohm D11-12= LED RED
R4= 10Kohm C1= 47uF 25V D13....17= 1N4148
R5= 220ohm C2-4=47nF 100V IC1= UAA180
R6-9=390ohm C3=2.2uF 25V IC2= TL072
All the Resistors is 1/4W 1% metal film

The described circuit serves as a level measurement device utilizing the UAA180 integrated circuit from SIEMENS, which functions as a high-precision audio signal level meter. This circuit incorporates a rectification stage with precision components to ensure accurate readings of incoming acoustic signals.

The calibration of the circuit is designed to adjust in increments of 3 dB, which allows for a clear visual representation of the signal level through the use of LEDs. The arrangement of the LEDs, which can be square, enables them to be stacked closely together, creating a bar graph display effect that provides an intuitive visual indication of signal strength without gaps.

In terms of components, the circuit uses a variety of resistors and capacitors to shape the response and functionality of the measurement system. The resistors, which include values such as 47 kΩ, 1 MΩ, and 220 Ω, are all rated at 1/4 watt with a tolerance of 1%, ensuring precision in the circuit's operation. The capacitors, including a 47 µF electrolytic capacitor and several 47 nF capacitors, are chosen to manage signal coupling and filtering effectively.

The use of the TL072 operational amplifier in conjunction with the UAA180 allows for enhanced signal processing capabilities, contributing to the overall precision of the level measurement. The circuit also includes various LED indicators to represent different levels of signal strength, with green LEDs indicating lower levels and yellow and red LEDs signaling higher levels, thus providing a comprehensive visual feedback system for the user.

Overall, this circuit design is suitable for applications requiring accurate audio level monitoring, making it an essential tool in audio engineering and sound system setups.This circuit of measurement of level uses the UAA180 of SIEMENS and a circuit of rectification of precision, round the IC2B. The calibration has become in steps 3db from the one Led in the other, ensuring, a very good rate of precision, in the measurement of entering acoustic signals.

The Led can be square, thus when they are placed the one by in the other, they give the picture of bar, without space. Part List R1= 47Kohm R7=2.2K ohm D1....8= LED GREEN R2= 1Mohm R8-10=330Kohm D9-10= LED YELLOW R3= 33Kohm R11=180Kohm D11-12= LED RED R4= 10Kohm C1= 47uF 25V D13....17= 1N4148 R5= 220ohm C2-4=47nF 100V IC1= UAA180 R6-9=390ohm C3=2.2uF 25V IC2= TL072 All the Resistors is 1/4W 1% metal film