Circuit Design Examples

Introduction

This repository showcases self-learning projects in electronics and RF engineering. Contributions or suggestions are welcome. Feel free to reach me out at andresmmera@protonmail.com

While my primary interest is RF engineering, this repo also includes general electronics designs. Bug reports or improvement ideas are appreciated.

Do you want to build this page locally? See this

Open-Source RF Engineering Software

The examples in this repo use the following tools:

Tool	Licensing	Notes
Qucs-S	GPL v2	GitHub Repo
Qucs-S S-Parameter Viewer	GPL v3	GitHub Repo
EMerge	GPL v2	GitHub Repo
Sonnet Lite	Proprietary software	Free license

RF Projects

Filters

#	Project	Filter Type	Frequency	Notes
RF.F.01	RF Filter Tutorial	LPF, HPF, BPF, BSF	500 MHz	Lumped LC. Canonical & Direct-Coupled
RF.F.02	RF Filters with Murata parts	HPF, BPF	500 MHz	Simulations with Murata pspice models
RF.F.03	MS Coupled-Line Filter	BPF	5000 MHz	BW = 400 MHz. RO4003C.
RF.F.04	MS Coupled-Line Filter with stubs	BPF	5000 MHz	BW = 400 MHz. RO4003C.
RF.F.05	MS Stepped-Z LPF	LPF	2000 MHz	RO4003C
RF.F.06	MS Quarter-Wave BSF	BSF	5000 MHz	RO4003C
RF.F.07	Lumped HPF with printed inductors	HPF	2000 MHz	RO4003C

Couplers

#	Project	Frequency	Notes
RF.C.01	Directional Coupler	2000 MHz	Microstrip. RO4003C
RF.C.02	Branch-Line	2000 MHz	Microstrip. RO4003C

RF Power Detector

#	Project	Frequency	Notes
RF.PD.01	Schottky Diode Power Detector	50 - 2000 MHz

System Design Notes

#	Project	Notes
RF.SYS.01	Intercept Diagram

General Electronics

#	Project	Notes
GE.01	How to use a PWM output to get an analog voltage	Get an analog voltage from a microcontroller PWM output
GE.02	How to use a MOSFET as a switch	Use NMOSFETs or PMOSFETs as low-side or high-side switches