Maker Factory ELECTRONICS EXPERIMENTS BOX Manual page 282

Fig. 3.98: Circuit 98 – Constant current power supply for LEDs
Circuits 98 and 99: The flat output characteristics of the emitter-to-ground circuit ensure that diode current
will not depend on the type of an LED.
Circuit 100: The functioning principle is described on page 259.
284
Fig. 3.99: Circuit 99 – Constant current power supply for LEDs
Fig. 3.100:
Circuit 100:
Electronic level
control