
Description: Ngspice is an open-source circuit simulator for electronics and semiconductors. It allows analyzing, modeling, and testing analog, digital and mixed-signal circuits with over 500 spice models of MOSFETs, BJTs, diodes, transformers, etc.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: BlackBoard Circuit Designer is a free online tool for designing and simulating digital logic circuits. It allows users to build circuits using logic gates like AND, OR, NOT, flip flops, etc. and see the simulation. It is good for education and learning about digital circuits.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API