[a.mehran]

This is an easy to build, but nevertheless very accurate and useful digital voltmeter. It has been designed as a panel meter and can be used in DC power supplies or anywhere else it is necessary to have an accurate indication of the voltage present. The circuit employs the ADC (Analogue to Digital Converter) I.C. CL7107 made by INTERSIL. This IC incorporates in a 40 pin case all the circuitry necessary to convert an analogue signal to digital and can drive a series of four seven segment LED displays directly. The circuits built into the IC are an analogue to digital converter, a comparator, a clock, a decoder and a seven segment LED display driver. The circuit as it is described here can display any DC voltage in the range of 0-1999 Volts.









PCB dimensions: 77,6mm x 44,18mm or scale it at 35%

انواع مقاومت برای انواع ولتاژ
0 - 2 V ............ R3 = 0 ohm 1%
0 - 20 V ........... R3 = 1.2 Kohm 1%
0 - 200 V .......... R3 = 12 Kohm 1%
0 - 2000 V ......... R3 = 120 Kohm 1%
----------------------------------------
R1 = 180k

P1 = 20k trimmer multi turn

R2 = 22k

U1 = ICL 7107

R3 = 12k

LD1,2,3,4 = MAN 6960 common anode led displays

R4 = 1M

 

R5 = 470k

 

R6 = 560 Ohm

 

 

 

C1 = 100pF

 

C2, C6, C7 = 100nF

 

C3 = 47nF

 

C4 = 10nF

 
C5 = 220nF


مدار تغذیه