FIELD: electric engineering.
SUBSTANCE: electronic unit of field instrument includes rheostat penetrated with supply current for adjustment and/or modulation of supply current, besides supply current is caused by supply voltage generated from the side of external power supply source. Electronic unit of field instrument further includes internal working circuit of signal processing to control field instrument, and also supply internal working circuit of signal processing applied to internal input voltage of electronic unit of field instrument separated from supply voltage, and internal supply circuit. Supply circuit includes useful voltage controller at least periodically penetrated with the first partial current of supply current, which generates mainly the first internal useful voltage in electronic unit of field instrument, and this voltage is permanently adjusted for the specified first level of voltage. Besides supply circuit has the second controller of useful voltage at least periodically penetrated with the second partial current of supply current, and it generates the second internal useful voltage that alternates in specified limits, and also voltage controller at least periodically penetrated with the third partial current of supply current for adjustment and fixation of internal input voltage of electronic unit in field instrument at specified level of voltage. According to invention, working circuit of signal processing is at least periodically penetrated with both the first useful current caused by the first useful voltage and the second useful current used by the second useful voltage.
EFFECT: reduction of power inputs and wider field of application.
47 cl, 13 dwg
