Programmable Current Source/Regulator
This is a simple circuit of programmable current source/regulator. This circuit is used to generate current. Here is the schematic diagram of programmable current source/regulator :

This circuit uses L 200 as main component. The error amplifier of this circuit is disabled by shorting pin 4 to ground. The value R is used to fix the output Io :
Io=(V5-2)/R
The output voltage can reach a maximum value Vi
– Vdrop=Vi 2 V (Vdrop depends on Io ).
[Source: SGS-Thomson Microelectronics Application Note]
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