This circuit solved a problem encountered in developing a portable device with an ARM Cortex-M0 processor. The power supply consisted of two AA batteries (2 × 1.5 V), and I needed to signal the user ...

A version of thie article appeared in the February 2012 issue of Test & Measurement World. See the PDF. Many industrial systems use the 4–20-mA loop to transmit measurements from sensors to displays, ...

Many MCU designs are intended to control power to devices such as motors, actuators, or other electronic subsystems. This power switching usually involves using a power device like a bipolar ...

Microcontroller port pins can typically be driven either high or low, or else be put into an "input" or high-impedance state. This circuit uses the three states to drive two separate LEDs with one ...