Current stabilizer with starting circuit

• US 4,567,426 A
• Filed: 03/30/1984
• Issued: 01/28/1986
• Est. Priority Date: 04/05/1983
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Sijbers, Peter J. M., van de Plassche, Rudy J.
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Rebsch, D. L.
• Application Number:
  US06/595,062
• Time in Patent Office: 669 Days
• Field of Search: 310/312, 310/313, 310/314, 310/315, 310/316, 310/901
• US Class Current: 323/315
• CPC Class Codes: G05F 3/265 using bipolar transistors only
• CPC Class Codes: Y10S 323/901 Starting circuits

Abstract

Two current circuits are between two common terminals (+V_B and -V_B). The ratio between the currents in the two current circuits is defined by a first current-dividing circuit, and the absolute values of these currents are defined by means of a second current-dividing circuit, in particular a resistor in this second current-dividing circuit. In order to ensure that the current-stabilizing assumes the proper state upon activation, a first current-supply circuit is coupled to the input of the second current-dividing circuit, which current-supply circuit comprises the series arrangement of a resistor and a transistor arranged as a diode, and a second current-supply circuit is coupled to the output of the current-dividing circuit, which second current-supply circuit includes a transistor whose base is connected in common with that of the transistor of the first current-supply circuit.

Claims

1. A current stabilizing arrangement comprising a first and a second current path between a first and a second common terminal, a first current-dividing circuit comprising transistors of a first conductivity type and having an input circuit with a low input impedance and an output circuit with a high output impedance, and a second current-dividing circuit comprising transistors of a second conductivity type and also having an input circuit with a low input impedance and an output circuit with a high output impedance, the first current-dividing circuit defining the ratio between currents flowing in the two current paths and the second current-dividing circuit defining the absolute values of the currents flowing in the two current paths and having a semiconductor junction connected in parallel with a series arrangement of a semiconductor junction and a first resistor, which current-stabilizing arrangement also comprises means for starting the current-stabilizing arrangement, characterized in that the means comprises a first current-supply circuit which supplies a current to the input circuit of the second current-dividing circuit and a second current-supply circuit which supplies a current to the output circuit of the second current-dividing circuit, the currents supplied by the first and the second current-supply circuit having a ratio which is equal to the ratio between the currents in the two current paths as defined by the first current-dividing circuit.

2. A current-stabilizing arrangement as claimed in claim 1, characterized in that the first current-supply circuit comprises a series arrangement of a transistor connected as a diode and a resistor, the resistor being coupled to the input circuit of the second current-dividing circuit, and the second current supply circuit comprises a transistor whose base is coupled to the base of the transistor of the first current-supply circuit.

3. A current-stabilizing arrangement as claimed in claim 1, characterized in that the first and the second current-supply circuit each comprise a transistor, which transistors have commoned bases which carry a reference voltage.

4. A current-stabilizing arrangement as claimed in claim 3, characterized in that the transistors of the first and the second current-supply circuit comprise a single transistor having a double collector.