PROTO circuit simulator alternative: digital logic from the transistor up
PROTO - circuit simulator is a realtime electronic circuit simulator app for Android on Google Play. You set up a circuit, run it, and check voltages, currents and other values, with animations of voltage and current flow and a four-channel oscilloscope. Its parts include AC, DC and waveform sources, resistors, capacitors, inductors, transformers, diodes, BJTs, MOSFETs, op-amps, a 555 timer and the digital gates with logic inputs and outputs, and it can use the phone's light sensor and accelerometer as circuit inputs. You can learn from built-in examples and video tutorials, share circuits and export them as PNG, JPG or PDF. It lists extra component packs, such as an Analog Pack, and has in-app purchases. PROTO simulates electronics on your phone, analog first with logic gates included; digiwleea is a guided lab for the logic inside a computer, in any browser.
What PROTO is good at
Trying out circuits on an Android phone before building them: set up a circuit, tune its values while it runs and read the signals on a four-channel oscilloscope, with examples and video tutorials to learn from. It is aimed at hobby projects with boards such as Arduino, Raspberry Pi and ESP32 as well as at learning. (digiwleea is an independent project, not affiliated with PROTO.)
How digiwleea is different
digiwleea concentrates on digital logic and runs in any modern browser, on phones, tablets and computers. You build the gates yourself from NMOS and PMOS transistors, then adders, latches, registers, RAM and an 8-bit CPU that runs a stored program, through a 40+ level course where every part is checked against its truth table, with an AI tutor (Wleea). It has no analog parts or oscilloscope: every wire is 0, 1 or floating, which keeps the focus on how logic and computers work. Use PROTO for voltages and waveforms, and digiwleea to see a computer come together.
| PROTO circuit simulator | digiwleea | |
|---|---|---|
| Focus | Analog and digital electronics | Digital logic, transistor to CPU |
| Runs on | Android (Google Play) | Any modern browser, including phones |
| Logic gates | Ready-made components | Built by you from transistors, then reused |
| Measurements | Four-channel oscilloscope, voltages, currents | Logic levels, truth tables, timelines |
| Price | Free to install; in-app purchases | Free lab and Act I; Premium for the full course |
No sign-up is needed to start: open the lab and place your first transistor, or read the free theory course. The account (and the AI tutor) are optional.
More comparisons: Logic simulators
See for yourself: build a logic gate from transistors in the simulator, then follow the path from sand to an 8-bit CPU.
Open the digiwleea lab →Frequently asked
Does PROTO simulate digital logic?
Yes. It includes AND, NAND, OR, XOR, NOR, XNOR and inverter gates with logic inputs and outputs, and its listing says it can be used as a logic circuit simulator.
Is PROTO circuit simulator free?
It is free to install from Google Play and has in-app purchases; its listing also names extra component packs, such as an Analog Pack.
Is there a browser alternative to PROTO for learning logic?
digiwleea runs in any current browser and teaches digital logic by having you build gates from transistors, then adders, memory and a CPU.