This circuit was designed to meet a medical application’s requirement to drive a laser diode with reasonable precision and a minimum of components and footprint (the device is now in clinical trials).

FET constant current sources use JFETs and MOSFETs to deliver a load current, which remains constant despite changes in load resistance or supply voltage. A FET constant current source is a type of ...

An avalanche photodiode (APD) delivers a useful electron-multiplier gain and generally improves signal-to-noise ratio (SNR) in optical communication systems. An APD is similar to a PIN photodiode with ...

It isn’t unusual to expect a precisely regulated voltage in an electronic project, but what about times when you need a precise current? Over on EDN, prolific [Stephen Woodward] explains how to use a ...