Power supply is indispensable for voltmeter circuit ICL7107 most commonly used in the market for this job (LCD-LED display, A / D converters) has integrated with-5v and +5 +5 volt single source we have two circuits Our first half is working with the +5 volt supply only source of PCBs to be a bit bigger but the circuit makes it attractive. The second circuit portion of the printed circuit quite small display control section, but feed on a single PCB symmetrical + – voltage
Voltmeter-1 http://www.reber.si/dvm/index.htm
R1 = 180k R2 = 22k R3 = 12k* R4 = 1M R5 = 470k R6 = 560
C1 = 100pF C2, C6, C7 = 100nF C3 = 47nF C4 = 10nF C5 = 220nF
P1 = 20k multi-turn U1 = ICL 7107 LD1,2,3,4 = 4 adet 7 segment Display
R 3 should be changed according to the voltage to be measured
0-20 V ….R3 = 1.2K
0-200 V …R3 = 12K
0-2000 V ..R3 = 120K
Password: 320volt.com
Published: 2008/03/20 Tags: analog circuits projects
Voice and Touch Switch Circuit
Circuit works both touch and voice. microphones in the window, door or blow into your home if it is connected and works with sound relay. Do not touch the pins on the relay circuit switches to manually contact paste and apply again until the sound again until it touches or holds permanent contact relay. RL resistance can take the relay instead of the integrated circuit and can remove. CD4013 integrated feature opening and closing constantly adds. While the supply pins to connect the integrated circuit to remember! (- VSS 7 + vdd 14)