Silicon ChipSPICE streamlines circuit design - June 2017 SILICON CHIP
  1. Outer Front Cover
  2. Contents
  3. Publisher's Letter: SPICE streamlines circuit design
  4. Feature: The Flettner Rotating Sail and the Magnus Force by Ross Tester
  5. Project: All-new 10-Octave Stereo Graphic Equaliser, Part 1 by John Clarke
  6. Project: Arduino-based Digital Inductance & Capacitance Meter by Jim Rowe
  7. Feature: LTspice – simulating and circuit testing, Part 1 by Nicholas Vinen
  8. Serviceman's Log: Fixing the food processor that wouldn't by Dave Thompson
  9. Project: El Cheapo Modules, Part 7: LED Matix displays by Jim Rowe
  10. Project: New Marine Ultrasonic Anti-Fouling Unit, Part 2 by Leo Simpson & John Clarke
  11. Feature: Getting Started with the Micromite, Part 4 by Geoff Graham
  12. Subscriptions
  13. Review: Keysight’s 9917A 18GHz Spectrum Analyser by Nicholas Vinen
  14. Product Showcase
  15. Vintage Radio: HMV’s 1951 portable model B61D by Associate Professor Graham Parslow
  16. PartShop
  17. Market Centre
  18. Advertising Index
  19. Notes & Errata: Micromite LCD BackPack V2 / ATmega-based Metal Detector with stepped frequency indication (Notebook Mar17)
  20. Outer Back Cover: Hare & Forbes Machineryhouse

This is only a preview of the June 2017 issue of Silicon Chip.

You can view 43 of the 112 pages in the full issue and the advertisments.

For full access, purchase the issue for $10.00 or subscribe for access to the latest issues.

Items relevant to "All-new 10-Octave Stereo Graphic Equaliser, Part 1":
  • 10-Octave Stereo Graphic Equaliser PCB [01105171] (AUD $12.50)
  • Front panel for the 10-Octave Stereo Graphic Equaliser [01105172] RevB (PCB, AUD $15.00)
  • 10-Octave Stereo Graphic Equaliser acrylic case pieces (PCB, AUD $15.00)
  • Pack of ten slide potentiometers for 10-Band Graphic Equaliser (Component, AUD $40.00)
  • 10-Octave Stereo Graphic Equaliser PCB pattern (PDF download) [01105171] (AUD $3.00)
  • 10-Octave Stereo Graphic Equaliser front panel artwork (PDF download) (AUD $3.00)
Articles in this series:
  • All-new 10-Octave Stereo Graphic Equaliser, Part 1 (June 2017)
  • Completing our new Graphic Equaliser (July 2017)
Items relevant to "Arduino-based Digital Inductance & Capacitance Meter":
  • Clear UB3 Lid for Arduino-based Digital LC Meter (PCB, AUD $5.00)
  • 16x2 Alphanumeric serial (I²C) LCD module with blue backlight (Component, AUD $7.50)
  • 1nF ±1% polypropylene (MKP) or C0G/NP0 ceramic capacitor (Component, AUD $2.50)
  • Firmware (Arduino Sketch) file for the Arduino-based Digital Inductance & Capacitance Meter [Arduino_LC_meter_sketch.HEX] (Software, Free)
  • Arduino-based Digital LC Meter front panel artwork (PDF download) (AUD $3.00)
Items relevant to "LTspice – simulating and circuit testing, Part 1":
  • Software for the LTspice Tutorial, Part 1 (Free)
Articles in this series:
  • LTspice – simulating and circuit testing, Part 1 (June 2017)
  • LTspice Part 2: Simulating and Testing Circuits (August 2017)
  • LTspice Tutorial Part 3: Modelling an NTC Thermistor (September 2017)
  • LTspice Simulation: Analysing/Optimising Audio Circuits (May 2018)
Items relevant to "El Cheapo Modules, Part 7: LED Matix displays":
  • MAX7219 controller (SMD) with pluggable 8x8 red LED matrix display (Component, AUD $5.00)
  • MAX7219 controller (DIP) with pluggable 8x8 red LED matrix display and jumper leads (Component, AUD $5.00)
  • MAX7219 controller (SMD) with red 8-digit 7-segment display (Component, AUD $7.50)
  • Software for MAX7219 (Free)
Articles in this series:
  • El Cheapo Modules From Asia - Part 1 (October 2016)
  • El Cheapo Modules From Asia - Part 2 (December 2016)
  • El Cheapo Modules From Asia - Part 3 (January 2017)
  • El Cheapo Modules from Asia - Part 4 (February 2017)
  • El Cheapo Modules, Part 5: LCD module with I²C (March 2017)
  • El Cheapo Modules, Part 6: Direct Digital Synthesiser (April 2017)
  • El Cheapo Modules, Part 7: LED Matix displays (June 2017)
  • El Cheapo Modules: Li-ion & LiPo Chargers (August 2017)
  • El Cheapo modules Part 9: AD9850 DDS module (September 2017)
  • El Cheapo Modules Part 10: GPS receivers (October 2017)
  • El Cheapo Modules 11: Pressure/Temperature Sensors (December 2017)
  • El Cheapo Modules 12: 2.4GHz Wireless Data Modules (January 2018)
  • El Cheapo Modules 13: sensing motion and moisture (February 2018)
  • El Cheapo Modules 14: Logarithmic RF Detector (March 2018)
  • El Cheapo Modules 16: 35-4400MHz frequency generator (May 2018)
  • El Cheapo Modules 17: 4GHz digital attenuator (June 2018)
  • El Cheapo: 500MHz frequency counter and preamp (July 2018)
  • El Cheapo modules Part 19 – Arduino NFC Shield (September 2018)
  • El cheapo modules, part 20: two tiny compass modules (November 2018)
  • El cheapo modules, part 21: stamp-sized audio player (December 2018)
  • El Cheapo Modules 22: Stepper Motor Drivers (February 2019)
  • El Cheapo Modules 23: Galvanic Skin Response (March 2019)
  • El Cheapo Modules: Class D amplifier modules (May 2019)
  • El Cheapo Modules: Long Range (LoRa) Transceivers (June 2019)
  • El Cheapo Modules: AD584 Precision Voltage References (July 2019)
  • Three I-O Expanders to give you more control! (November 2019)
  • El Cheapo modules: “Intelligent” 8x8 RGB LED Matrix (January 2020)
  • El Cheapo modules: 8-channel USB Logic Analyser (February 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules (May 2020)
  • New w-i-d-e-b-a-n-d RTL-SDR modules, Part 2 (June 2020)
  • El Cheapo Modules: Mini Digital Volt/Amp Panel Meters (December 2020)
  • El Cheapo Modules: Mini Digital AC Panel Meters (January 2021)
  • El Cheapo Modules: LCR-T4 Digital Multi-Tester (February 2021)
Items relevant to "New Marine Ultrasonic Anti-Fouling Unit, Part 2":
  • Pair of CSD18534KCS logic-level Mosfets (Component, AUD $6.00)
  • New Marine Ultrasonic Anti-fouling unit lid panel artwork (PDF download) (AUD $3.00)
Articles in this series:
  • New Marine Ultrasonic Anti-Fouling Unit (May 2017)
  • New Marine Ultrasonic Anti-Fouling Unit, Part 2 (June 2017)
Items relevant to "Getting Started with the Micromite, Part 4":
  • Software for the Micromite Tutorial, Part 4 (Free)
Articles in this series:
  • Getting Started with the Micromite (February 2017)
  • Getting Started with the Micromite, Part Two (March 2017)
  • Micromite Tutorial, Part 3: strings and arrays (May 2017)
  • Getting Started with the Micromite, Part 4 (June 2017)

Purchase a printed copy of this issue for $10.00.

SILICON SILIC CHIP www.siliconchip.com.au Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Editor Nicholas Vinen Technical Editor John Clarke, B.E.(Elec.) Technical Staff Ross Tester Jim Rowe, B.A., B.Sc Bao Smith, B.Sc Photography Ross Tester Reader Services Ann Morris Advertising Enquiries Glyn Smith Phone (02) 9939 3295 Mobile 0431 792 293 glyn<at>siliconchip.com.au Regular Contributors Brendan Akhurst Ian Batty David Maddison B.App.Sc. (Hons 1), PhD, Grad.Dip.Entr.Innov. Associate Professor Graham Parslow Dave Thompson SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. ACN 003 205 490. ABN 49 003 205 490. All material is copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing and Distribution: Derby Street, Silverwater, NSW 2148. Subscription rates: $105.00 per year in Australia. For overseas rates, see our website or the subscriptions page in this issue. Editorial office: Unit 1 (up ramp), 234 Harbord Rd, Brookvale, NSW 2100. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9939 3295. E-mail: silicon<at>siliconchip.com.au ISSN 1030-2662 Recommended & maximum price only. 2  Silicon Chip Publisher’s Letter SPICE streamlines circuit design This month’s tuitional article on the topic of SPICE simulation (page 38) will have a particular interest for readers who would like an insight into the ways in which we produce the circuits for our projects. These days we seldom bother with building a “bird’s nest” or a protoboard layout on the workbench. There are a number of reasons for this. First, the components are simply too small and usually have too many pins to produce a bird’s nest. Second, even if we did wire up a bird’s nest or a protoboard, the stray wiring capacitance and inductance would be so unpredictable that reliable operation would be unlikely. Or if it did work by some fluke, it might be very hard to reproduce the same performance on a PCB. Second, the key devices in many circuits are now surface-mount types and the only way to wire these into a prototype layout would be to use adaptor boards of some sort. Even then, stray wiring capacitance and inductance would be a problem. Finally, many of our microprocessor circuits, particularly those using the PIC16F88, are variations on past themes and the real “smarts” are in the software. The major part of the design is in writing and debugging the program. So in virtually every project these days, we proceed directly to producing a prototype PCB, designed using the powerful and highly regarded CAD package, Altium Designer (produced in Australia, by the way). Part of the design process for the PCB will involve trying to make provision for any circuit changes which might prove to be necessary, without producing another iteration of the board. If this can be done successfully, we save time and money. But the PCB design does not simply involve using a pencil circuit sketch or a more elegant CAD rendition which becomes the “netlist”. In the case of most analog circuits, we need to run SPICE simulations to ensure that the proposed design will actually work. In fact, SPICE simulation takes the place of the bird’s nest or the more elaborate protoboard layout. As described in this month’s article on SPICE simulation, this process allows as many iterations as we need, to be confident that the circuit will work as intended. Nor is there any need to do any instrument testing, because the SPICE program will simulate that too. So for example, SPICE can show how a filter circuit will respond to an impulse, or model the input surge current into a power supply, or show how deliberate overloads will affect the circuit – all without blowing a single fuse or letting the “smoke out” of any expensive semiconductors. However, despite all that initial simulation, after assembling the prototype PCB we sometimes find that the performance is not what we wanted. This can happen no matter how carefully the PCB has been laid out – and this happened with the Graphic Equaliser in this month’s issue. You can see that there would be no practical way in which that circuit could be prototyped in the traditional way – it is simply too large and complicated. Perhaps inevitably though, the initial performance of the prototype PCB was not up to scratch. Its boost and cut were excessive and the distortion and residual noise were too high. And here I will let you into a secret: we had not done any initial SPICE simulations, because the circuit was a miniaturised variation of a design we presented back in 1989. Sorting out the problems with the prototype could have taken many days of component changes and subsequent testing but we did not have time for that. Instead, we simply did a few SPICE simulations of the key circuit sections and this pointed to the solution. The results can be seen on page 18 of this issue. Leo Simpson siliconchip.com.au