.. Reference Woodward, Stephen. A negative current source with PWM input and LM337 output. Materials on the topic Datasheet Fairchild LM317 Datasheet ON Semiconductor LM337 Datasheet Analog Devices LM4041 Datasheet Infineon BSS308PE ...
.. with a voltage doubler charge pump circuit. Materials on the topic Datasheet Texas Instruments SN74HC14 Datasheet Fairchild 1N5819 discovercircuits.com
.. current mirror that is. Chapter 11: The Current Mirror Materials on the topic Datasheet Texas Instruments LMC555 Datasheet Fairchild 2N3906 Datasheet Central Semiconductor 2N5087 Datasheet ON Semiconductor 2N5089