EP 0731403 A2 19960911 - Constant current source
Title (en)
Constant current source
Title (de)
Konstantstromquelle
Title (fr)
Source de courant constante
Publication
Application
Priority
US 39907995 A 19950308
Abstract (en)
A current source for generating a current that is relatively stable over variations in the power supply voltage and temperature, and over variations in process parameters is disclosed. The current source includes a bias circuit, for producing a compensating bias voltage, and a current mirror. The bias circuit utilizes a voltage divider to generate a divided voltage based on the power supply value. The divided voltage is applied to the gate of a modulating transistor (biased in saturation) in a first current mirror, which controls a current applied to a linear load device. The voltage across the load device determines the bias voltage, which is in turn applied to the gate of a transistor in the reference leg of a second current mirror. The bias voltage controls the current in the reference leg of the second current mirror, and an output leg mirrors the second reference current to produce a stable output current. <IMAGE>
IPC 1-7
IPC 8 full level
G05F 3/26 (2006.01); H03F 3/343 (2006.01); H03F 3/347 (2006.01)
CPC (source: EP)
G05F 3/262 (2013.01)
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0731403 A2 19960911; EP 0731403 A3 19970723; JP H08263158 A 19961011
DOCDB simple family (application)
EP 96301270 A 19960226; JP 5191496 A 19960308