Abstract A stabilized current output circuit having a DC power source with a pair of terminals, a series circuit consisting of m number of diodes which is connected at one end thereof to one terminal of the DC power source and at the other end thereof to the other end of the DC power source, a first transistor forming a first current mirror circuit together with the last diode of the series circuit located nearest to the other terminal of the DC power source, the last diode being connected between the base and emitter of the first transistor, a first resistor connected between the first diode of said series circuit and said one terminal, a second resistor connected between the collector of the first transistor and the one terminal of the DC power source, a diode connected between the collector of the first transistor and the other terminal of the DC power source, and an output transistor which is connected at the base thereof to the collector of the first transistor. In this case, the output transistor and the last-mentioned diode form a second current mirror circuit, and the resistance values of the first and second resistors are selected in connection with the number m to produce a stabilized constant current at the collector of the output transistor.
A stabilized current output circuit comprising: (a) a DC power source having a pair of terminals; (b) a series circuit consisting of a first resistor and m number of diodes, said series circuit being connected at one end thereof to one terminal of said DC power source and at the other end thereof to the other terminal of said DC power source; (c) a first transistor which forms a first current mirror circuit together with the last diode of said series circuit located closest to said other terminal of said DC power source, said last diode being connected between the base and emitter of said first transistor; (d) a second resistor connected between a collector of said first transistor and said one terminal of said DC power source; (e) a diode connected between the collector of said first transistor and said other terminal of said DC power source; and (f) an output transistor whose base is connected to the collector of said first transistor, said output transistor and last-mentioned diode forming a second current mirror circuit, wherein resistance values of said first and second resistors are selected in connection with said number m to produce a stabilized constant current at the collector of said output transistor.
Claim 2
Dependent Claim
206 words
A stabilized current output circuit comprising: (a) a DC power source having a pair of terminals; (b) a series circuit consisting of a first resistor and m number of diodes, said series circuit being connected at one end thereof to one terminal of said DC power source and at the other end thereof to the other terminal of said DC power source; (c) a first transistor which forms a first current mirror circuit together with the last diode of said series circuit located closest to said other terminal of said DC power source, said last diode being connected between the base and emitter of said first transistor; (d) a second resistor connected between a collector of said first transistor and said one terminal of said DC power source; (e) a diode connected between the collector of said first transistor and said other terminal of said DC power source; and (f) an output transistor whose base is connected to the collector of said first transistor, said output transistor and last-mentioned diode forming a second current mirror circuit, wherein resistance values of said first and second resistors are selected in connection with said number m to produce a stabilized constant current at the collector of said output transistor.
Claim 3
Dependent Claim
36 words
A stabilized current output circuit according to claim 1, wherein each of said m number of diodes and the last-mentioned diode is a diode-connected transistor where the collector and base thereof are connected to each other.
Claim 4
Dependent Claim
67 words
A stabilized current output circuit according to claim 2, wherein the emitter area ratio of said first transistor and said last diode-connected transistor of said series circuit is selected n:1, the emitter ratio of said output transistor and last mentioned transistor is selected l:1, and resistance values R 5 and R 0 of said first and second resistors are selected to satisfy R 5 =mnR 0 .
Claim 5
Dependent Claim
56 words
A stabilized current output circuit according to claim 3, wherein the number m of said diodes in said series circuit is selected to be 2, the values l and n are both selected as 1, and the resistance value of said first resistor is selected to be twice as much as that of said second resistor.