User: can you recommend some electornics circuit simulators ? i want to build a simple 1 bit CPU / computer  from scratch using electronic components. i would rather use real world components but i think i should start with virtual simulators.
Assistant: Building a 1-bit CPU or computer from scratch is an ambitious and educational project! Starting with a simulator is a great idea as it allows you to test and iterate your designs without dealing with hardware failures or shortages. Here are some popular electronics circuit simulators you might find helpful:

1. **LTSpice**: Developed by Linear Technology (now Analog Devices), LTSpice is a powerful and widely-used circuit simulator. It’s especially well-suited for analog circuits but can also handle digital components. It’s free and has a large library of components.

2. **Multisim**: Offered by National Instruments, Multisim is a versatile and user-friendly circuit simulator that is commonly used in academia. It provides comprehensive support for both analog and digital circuits, along with a rich database of components.

3. **TINA-TI**: This is a version of the TINA simulator provided by Texas Instruments. It’s a powerful simulation tool for analog, digital, and mixed-signal circuits. It’s free and specifically optimized for Texas Instruments components.

4. **QUCS (Quite Universal Circuit Simulator)**: This is an open-source circuit simulator that provides a graphical user interface to simulate a variety of electrical circuits. It supports both analog and digital simulations.

5. **Proteus**: Known for its ability to simulate microcontroller applications, Proteus is a popular choice for projects involving digital components and microcontrollers. It offers a comprehensive suite for PCB design alongside simulation.

6. **Logisim**: Specifically designed for educational purposes, Logisim is an easy-to-use digital circuit simulator that’s great for learning about logic circuits and computer architecture. It’s particularly useful for constructing CPU designs and can handle 1-bit operations quite well.

7. **Fritzing**: While more of a prototyping tool, Fritzing allows you to create and simulate simpler circuits. It’s more focused on beginners and hobbyists, providing a bridge between the design and the real-world breadboard implementation.

8. **CircuitLab**: An online circuit simulation platform, CircuitLab offers both free and paid plans. It supports mixed-signal simulation and provides a community-driven component library.

9. **KiCad**: Best known as a PCB design tool, KiCad also includes circuit simulation features. It’s open-source and offers a comprehensive suite for electronics design.

10. **Online Platforms**: Websites like EasyEDA and CircuitMaker provide powerful tools for schematic capture and simulation, with the added benefit of being cloud-based for easy collaboration.

Each of these tools comes with different features that might be beneficial depending on various aspects of your project. It's a good idea to try a few to see which one suits your workflow best.
User: i value speed and performance of simulation , what are my options in order to  have the fastest performance ? also which software do professionals use in order to simulate electronic circuits , more specifically in the field of cpu design .
Assistant: