Ω Fresh look, improved user interface! • This last update brings a complete view navigation redesign with modernized view handling, fully optimized for iOS 26. Ω Audio Function Generator • new Balance control! Easily adjust the left/right stereo output for precise sound shaping. • Several improvements to musical notes playback Ω smaller fixes and improvements

Ω updates for iOS 26 Ω Audio Function Generator • new Balance control! Easily adjust the left/right stereo output for precise sound shaping. • Several improvements to musical notes playback Ω smaller fixes and improvements

Ω New Zoom Feature • added zooming support globally for all schematics, images, and formulas. • Now you can easily enlarge and examine details more closely. • Enjoy improved visibility and a more flexible experience. Ω New interactive graphs with cursor: • Low-pass, high-pass filter (Cut-Off frequency tool) • Charging and discharging of a capacitor Ω New Tools (Capacitor Charge Tools) • Inrush Current Limiter using NTC including interactive graph and cursor • Capacitor Quiescent Current calculator including interactive graph and cursor Ω New custom database for datasheets • easily manage your project datasheets with the new custom database feature! • access and store important project information directly from the new menu entry of the sidebar • keep everything organized and readily available whenever you need it Got questions or suggestions? Reach out to us at tom@ee-toolkit.com. If you're enjoying the app, please take a moment to leave a review — it makes a big difference!

Ω IC Logic Guide (Logic Gates Tool): overview of the most common process technologies / device families Ω Additions to the SBC Tools section Ω User Interface optimisations and improvements Ω Smaller fixes and improvements all over the App

Ω Audio Function Generator • significant rewrite of the function generator core functions, including an improved Audio Engine, enhanced power state management and many more core improvements. • improved Tap-To-Save feature for all page. • various UI cleanups have been implemented. Ω Other • Switches Tool improvements • User Interface optimisations • Fixes and improvements all over the App

Ω New Tool about the Kirchhoff circuit laws (Basic Tools) • Explains the two fundamental and related Kirchhoff's laws, the junction rule and the loop rule using an example circuit. Ω Audio Scope • better arrangement of the scope window and the control elements • option to increase the size of the FFT frequency label Ω Audio Function Generator • Noise Engine optimisations Ω Other • Positive + Negative Voltage Regulator Tool improvements (nearby results) • Fixes and improvements all over the App

Ω Audio Function Generator: • Redesigned Fine-Tune popover! • change the tone amplitude and the system volume independently • change the volume in % or in dB • custom configuration of the volume step size • custom configuration of the frequency step size • Several user interface changes and improvements Ω New temperature sensor tool (“Nonlinear R” tools) Ω Audio Scope improvements (FFT label) If you have any questions or suggestions, please feel free to email us at tom@ee-toolkit.com.

Ω New Tools: • Basic Tools: two more T pad and two more Pi Pad tools. Adding symmetric T/Pi pad circuits and additional T/Pi pads, which calculate the return loss and the attenuation based on the values of the input resistors and the impedance of the system. • Frequency Tools: new Fourier series tool. Illustrates how the Fourier expansion works (the number of harmonics can be set as desired within the range of 0 - 50). Ω Audio Function Generator: • Scope View optimisations (moving the waveforms, calculating the cycle duration) • BPM feature optimisations (adding fine-tuning and slider) • Audio Engine optimisations for all non-sine signals • Improved visualisation of the phase view popover • Variable sweep time calculation fix Ω Added option to copy numbers from calculated fields Ω Better readability of the control elements in Dark Mode Ω Fixed the diagram of the center tapped transformer rectifier (rectifier tools) Ω Fixes and improvements all over the App If you have any questions or suggestions, please feel free to email us at tom@ee-toolkit.com.

Ω Audio Scope: • major re-design of the controls and the FFT mode. In FFT mode, the frequency of the signal with the highest amplitude is now displayed. Ω Audio Function Generator: • now supporting 3x16 frequency presets, all fully customisable. Use the arrow buttons to switch between them or just slide the controls. • new setting to change the frequency sliders step size (0.01 – 100).

Audio Scope FFT mode bugfix

New Tools: Ω TL431 tool about the popular three-terminal adjustable shunt regulator Ω Full wave rectifier with center tab Improvements: Ω Audio Scope: improved FFT mode (more scaling options, higher accuracy) Ω Zener Diode Tool: additional input for the load current Fixes: Ω 7-segment LED Tool display bugfix

Ω Fixed loading issue of the 7400 tool

New Tools: Ω Frequency Tools: new tool for calculating the load capacitors of a crystal oscillator circuit Ω 555 Tools: example of a power on delay circuit using the 555 Timer IC Ω Capacitor Tools: new tool for demonstrating charging of a capacitor using a constant current source Extended Settings: Ω new global setting for preferred E-Series and tolerance of components

Ω Function Generator • Frequency Sweep: added new sweep option. You can now choose between fixed and variable frequency sweeps. A custom sweep step size (Hz) and a custom sweep step duration (s) can be freely selected. This gives you a whole new way to customise your frequency sweeps! • repeated Play/Pause caused R+L signals going out of phase in some cases. This is now fixed. • change popup styles Ω SBC Tools • added new section for Espressif Systems modules and boards • updated datasets of all the other SBC Tools Ω PCB Trace Width Tools • added option to enter a custom ρ (Rho) value Ω Smaller fixes and improvements all over the App

Ω bugfixes and improvements

Ω New Tools: • Center Frequency Tool for calculating the center frequency and Q-factor of a bandpass or notch filter • LED delay circuit using an RC circuit and a NPN transistor Ω Function Generator: • Dual-Tone: Fixing distortions when changing frequency during playback. Fixing an issue with the phase value not being applied when restarting or when changing tabs • Music Notes: added play/pause button to the music notes view Ω Smaller fixes and improvements all over the App

Ω bugfixes and improvements

Ω The EE ToolKit now also runs on Mac computers with Apple silicon

Ω Function Generator: • several usability optimisations and improvements • fixing an issue with frequency input range checks • fix for volume change events not working anymore with iOS 15 • optimisations for the preset settings popover (first Tab) Ω support for iPad mini 6 Ω bugfix for the PCB Trace Width tool Ω Smaller fixes and improvements all over the App

Ω New Tools: • BCD to 7-Segment using 74HC4511 (LED Tools) • LED dot/bar application using LM3914 (LED Tools) • Bit to dB tool for converting Bit depth to Decibels (Decibel Tools) Ω Function Generator: • new Fine-tune popover for fine-tuning frequency and amplitude • new system volume popover • fixed memory leak in the Sweep repeat implementation • repeat button in the Sweep tab now has 3 functions: off, repeat, siren-mode • refactored Master Volume control • added fine-tuning option to the musical notes section Ω Tools which use ICs in the example schematic have a link to the PDF datasheet of that respective IC now accessible via a sidebar link Ω Corrected swapped Vin and RL description in the loaded voltage divider tool Ω Fixed a bug in the Diodes tool Ω Corrected formula for the PCB Trace Width tools Ω Smaller fixes and improvements all over the App

The brand-new EE ToolKit is here! Happy to present great new tools, great improvements and handy new feature additions. Ω New Tools: • Comparator tools (inverting, non-inverting). Easy to understand and very useful for experimenting with OpAmp comparator circuits. With comprehensive additional explanations and illustrations. Available via the OpAmp Circuit Tools. • Schmitt-Trigger tools / Comparator with Hysteresis (inverting, non-inverting). Easy to understand and very useful for experimenting and learning about comparator circuits with hysteresis. Additional text explaining how comparators can be extended to support hysteresis and thus two different threshold levels. Available via the OpAmp Circuit Tools. • Inrush current calculator for Load Switches (using the TPS2292x from Texas Instruments as an example). This is part of the Capacitor Charge Tools. Ω Notes: from this version onwards, you can save own drawings plus text notes for each tool individually. An overview of all stored notes and drawings is provided via the side menu on the main page. Ω Zooming on info pages on iPads is working much smoother now Ω Frequency Pitch Detector is now fully unlocked also in the free version Ω Smaller fixes and improvements all over the App

Ω consolidated App versions Ω bugfixes and improvements

Ω updates for iOS 14 Ω new Notes popover. Now you can make notes for each tool individually. Via the home screen you can get an overview of all of your notes.

Ω Component Tools: • added new tool for the 4000 IC Series (consists of 127 different ICs) • improved search function of the 7400 tool • fixed datasheets of Diodes tool not loading issue Ω Single Board Computer Tools: • added 6 more Orange Pi boards (Orange Pi 4B, Orange Pi 4, Orange Pi Zero LTS, Orange Pi 3, Orange Pi 3g-Iot-B, Orange Pi 3g-Iot-A) • added Teensy Boards • fixed page size issue for iOS devices without a home button • fixed image invert issue in SBC tools and Info pages Ω Audio Function Generator: • support for AirPlay 2 with multi-room • new “AUTO” button in the oscilloscope view. • the Min/Max frequency slider values and the max sweep slider value are now changed to buttons that open a popup window for immediate means to enter a new value. Browsing to the settings page to change these values is no longer needed. • musical notes popover has been improved. The window size and button size are now as large as possible for each respective iOS device. • added settings option to allow mixing of audio with external sources. Please Note: for streaming audio over AirPlay 2, this option must be disabled. • fixed oscilloscope issue when frequency slider is set to logarithmic. • fixed a phase issue in the Dual Function Generator. When changing frequencies, the phase went out of sync in some cases. • timed playback fix in the Dual Tone Generator • sweep counter resets to the exact start value when completed Many other optimizations and improvements under the hood to make the App more future proof for upcoming iOS versions, screen size changes, etc.

- fixed misaligned images in the active filters tool - fixed a calculation error in the loaded voltage divider tool