This issue of Electronic Engineering Times includes: News Brief, In-Depth, Precision Timing, Using USB to Charge Batteries, Design Idea, Using a Digital Potentiometer for Voltage-to-Resistance Conversion, Building a Charge Pump Using GPIO Expanders to Drive a Blue LED, and Using the High-Power USB Port to Charge a Single 2100mAh NiMH Battery.
The Maxim Engineering Journal presents a collection of technical articles. It includes a news brief, a discussion of integrated DC logarithmic amplifiers, and precision timing topics. Design examples show how to use digital potentiometers for voltage‑to‑resistance conversion and how to drive blue‑LEDs with a GPIO expander.
The journal also provides circuit diagrams, equations, and practical tips for implementing log‑amplifier circuits such as the MAX4206, including supply‑voltage options, temperature‑compensation techniques, and layout recommendations. This manual is written in Chinese.