eCircuit Center – Spice Schematics

“The goal is a site where the learning of electronics is hands-on and fun. And the SPICE circuit simulator is a great software tool to achieve that goal. It hit me the first time I used SPICE – simulating is fun! And because it’s easy to use, I’ve spent a lot of time building and exploring circuits.” – Rick

eCircuit Center – Spice Schematics

SPICE is capable of performing both AC (frequency) Analysis and Transient (time) Analysis. SPICE also performs a number of other analyses like DC, Sensitivity, Noise and Distortion.

SPICE Basics, SPICE Commands, Circuit Collection

eCircuit Center - Spice Schematics

“At the core of the function generator is a triangle wave generator. How do you generate a triangle wave? The most common way is to get a capacitor and then alternate charging it and discharging it. But how to you get a nice linear ramp across the capacitor?”

Triangle and Square-Wave Generator

Simulation Circuit Examples –

  • Programmable Gain Amplifier (PGA) Op Amp
  • Single-Supply AC Inverting Amplifier
  • Instrumentation Amp (3 Op Amp)
  • Sensor Bridge with Current Bias
  • The PID Controller
  • Pulse Width Modulation
  • Precision Half-Wave Rectifier

PWM Control Circuit – TL494

The TL494 incorporates all the functions required in the construction of a pulse-width-modulation (PWM) control circuit on a single chip. Designed primarily for power-supply control, this device offers the flexibility to tailor the power-supply control circuitry to a specific application.

PWM Control Circuit – TL494

  • Complete PWM Power-Control Circuitry
  • Uncommitted Outputs for 200-mA Sink or Source Current
  • Output Control Selects Single-Ended or Push-Pull Operation
  • Internal Circuitry Prohibits Double Pulse at Either Output
  • Variable Dead Time Provides Control Over Total Range
  • Internal Regulator Provides a Stable 5-V Reference Supply With 5% Tolerance
  • Circuit Architecture Allows Easy Synchronization

PWM Control Circuit - TL494

The TL494 contains two error amplifiers, an on-chip adjustable oscillator, a dead-time control (DTC) comparator, a pulse-steering control flip-flop, a 5-V, 5%-precision regulator, and output-control circuits.

TL494 Related Links

Open Circuits – Open Source Electronics

Open Circuits is a wiki for sharing open source electronics knowledge, schematics, board layouts, ports and parts libraries. This include open hardware Music Players, atomic microscopes, PC, PDA and mobile phones, and batteries. Please help us to build this resource by submitting your component descriptions, projects, techniques, and PCB footprints.

Open Circuits – Open Source Electronics

Some Projects that look Interesting are

  • Multi-purpose Embedded System
  • dsPIC33 Development Board
  • ADuC832 Development Board
  • N8VEM Home Brew Computing Project

The Open Source Movement, typically covers Open Hardware, Open Firmware, and Open Software. The Open Firmware movement provides firmware which you may also know as soft-IP or FPGA coding see Open Cores for more details.

Excellent examples of Open Hardware projects range from projects at OpenCircuits to Tiny Embedded Ethernet Devices and Advanced & Intelligent Camera Designs which provide solid-state camera and FPGA assisted hardware designs. A solid overview of projects can also be found at Open Innovation Projects.