Constant current source,申请号US19810276943-传众专利搜索

Constant current source

申请公布号：US4352057(A)

申请号：US19810276943

申请日期：1981.06.24

申请公布日期：1982.09.28

申请人：

SONY CORPORATION

发明人：OKADA, TAKASHI;SAHARA, HIROSHI;OTSUKA, FUMIKAZU

分类号：G05F3/16;G05F3/22;G05F3/26;H03F3/347;(IPC1-7):G05F3/16

主分类号：G05F3/16

摘要：A constant current generating circuit is provided which comprises first, second, third and fourth transistors of one conductivity type, each having base, emitter and collector electrodes, and a voltage supply source having first and second voltage terminals. In this case, the collector and emitter electrodes of the first transistor are respectively connected to the first and second voltage terminals with a first impedance between the collector electrode and first voltage terminal; the emitter electrode of the second transistor is connected to the second voltage terminal through a second impedance; the emitter electrode of the third transistor is connected to the second voltage terminal through a third impedance; the emitter electrode of the fourth transistor is connected to the second voltage terminal; the base electrode of the first transistor is connected to the emitter electrode of the second transistor; the collector electrode of the first transistor is connected commonly to the base electrodes of the second and third transistors; the emitter electrode of the third transistor is connected to the base electrode of the fourth transistor; and a current utilizing means is connected between the first voltage terminal and at least one of the collector electrodes of the second, third and fourth transistors.