January 2018

High-Power DC 60V/ 40A Motor Speed Controller (Part 1)

If you’re into high-power robot-wars or electric buggies then our latest motor control design is perfect for DC motors operating up to 60V and currents up to 40A. It’s packed with features including back-emf speed regulation, soft start, emergency stop, max speed limiter and low battery shut down.

It can be configured for high-side or low-side switching, depending how your motor is supplied.  Use with any suitable universal DC motor, permanent magnet, series or shunt wound. PIC microcontroller-powered with free hex code available. Constructional details are provided in Part 2 next month.

Each month’s download link will be found under the magazine cover shot (right, top)

SC200 Amplifier Module (Part 1)

This completely new amplifier circuit incorporates most of the features of modern amplifier modules, but uses through-hole PCB construction for ease of assembly and it has a number of neat touches to help get the best out of its performance, including clipping indicators and fault-tolerant circuitry.

The SC200 is rated at 200W into a 4 ohm load.  Part 2 next month describes performance and construction of the SC200.

Please Take Note – SC200 Components List
At the time of writing the FJA4313OTA is available from Digi-Key or as part of a set of hard-to-get parts from the SILICON CHIP Online Shop.

The transformer specification should be 40-0-40 not 45-0-45V.

LED1 is supplied with around 2mA so any blue LED of that size should be fine. The forward voltage is not important as the circuit will automatically adjust to compensate (it’s supplied from a constant current source). – Nicholas Vinen

Arduino Meets the ATtiny85 Microcontroller

This enjoyable and informative article explores ATtiny85 microcontrollers – very compact and versatile, they turn up by the million in industry and consumer products. This walk-through explains their architecture  and offers some simple demo applications.

Using Cheap Asian Electronics Modules (Part 1).

The first in a short series offers guidance for utilising cheap and cheerful, pre-built modules that are now popularly available online. This month the DS3231 real-time clock (RTC) is put under the microscope, showing how to use a typical RTC in your applications.

Teach-In 2018 – Get Testing!
Part 4: Component measurement

Our series devoted to choosing and using test gear this month investigates techniques for checking out many discrete components including capacitors, inductors and diodes. If you’re a novice or student in electronics, this special series will show you how to handle a multimeter with confidence and interpret the test results.

Also in this issue

• Techno Talk – reminiscing about how hobby electronics has changed over the past 60 years
• Net Work  – getting same day delivery when buying online; the EPE Chat Zone finds a new home on EEWeb
• PIC n’ Mix – our PIC microcontroller expert continues with Part 2 of a short series about utilising 4-digit 7-segment displays
• Circuit Surgery – An in-depth series on using temperature sensors concludes with Part 4 this month.
• Max’s Cool Beans Blog – Max muses about some of his latest personal projects
• Audio Out – Power supply design and assembly techniques
• Electronic Building Blocks – an LED VU Meter from a pre-built low cost imported module.

Next month:

GPS-synchronised Analogue Clock Driver – automatically sets itself to the right time and includes Daylight Saving as well. SC200 Audio Amplifier (Part 2) – Part 2 showing construction details. DC Motor Speed Controller (Part 2) – assembly and setup. Teach-In 2018 (Part 5) inductors, resonant circuits and quartz crystals.