UAA180 based VU Meter Circuit Schematic With Explanation

The circuit was designed based on the operation of Siemens UAA180 as it functions as a LED driver for light band displays for measuring the level of audio signals.

Part List
R1----22K--1/4W
R2----27K--1/4W
R3----33K--1/4W
C1----1nF
D13---1N4148
P1-----10K--TRIMMER
IC1----UAA180
D1...12-LEDS