LIGHT-EMITTING DIODE INDICATOR FOR MONITORING VOLTAGE LEVEL Russian patent published in 1996 - IPC

FIELD: measurement technology. SUBSTANCE: light-emitting diode indicator for monitoring voltage level has light-emitting diodes 1-4 inserted in drain circuits of field-effect transistors 5-8 whose sources are connected through resistors 9-11 to ground, coupling resistors 13-16, diodes 17-20 connected to gates of field-effect transistors 5-8, photodetector amplifier 21, controlled generator 22, resonance-tuned LC circuits at input of field-effect transistors 5-8 set up of inductance coils 23-26 and capacitors 27-30, 31-34, limiting resistors 35-38, isolating resistors 39-42 at output of controlled generator 22, selector switch 43, RC filter built up of resistor 44 and capacitor 45, diode 46, amplifier 47, monitored current supply 48, D.C. current supply 49, selector switch 50, and power supply 51. EFFECT: enlarged functional capabilities. 3 dwg