Online Design and Simulation of the LT8609 Step-Down Regulator

Online Design and Simulation of the LT8609 Step-Down Regulator

We’ve created a new video tutorial that explores how to quickly and accurately design and simulate power management circuits with TINACloud, this time using the LT8609 synchronous step-down switching regulator as an example. You can also use the offline TINA program for this, which we’ll illustrate in another video. The SPICE model for this device, created by DesignSoft from the official Analog Devices datasheet, is compatible with most major SPICE programs, including TINA, TINACloud, PSpice, SIMetrix, and LTspice. 

Here is a summary of the video’s content:

  • Startup Transient Analysis
  • Output Voltage Ripple
  • Line and Load Step Analysis
  • AC Analysis
  • Efficiency Analysis

1. Startup Transient Analysis

A startup transient is the period a DC-DC converter takes to transition from an off state to its steady-state operating condition. Typically, simulating this can be time-consuming. However, TINA and TINACloud’s built-in average model significantly speeds up the process, taking only a few seconds. For more detailed results, the software can also perform a switching mode transient analysis, which is still quite fast thanks to its advanced multi-core solvers. Additionally, TINA and TINACloud can quickly calculate ripple voltages by combining the average and switching models.

To begin, we’ll open the “LT8609 Multiple Simulations.TSC” circuit file. This single file allows you to run all the necessary simulations to characterize the LT8609.

Running a Simulation

To perform a fast transient analysis using the average model, click the Transient Analysis Fast link or select Transient… from the Analysis menu. By default, the “Use switching model” checkbox is unchecked, which ensures the fast average model is used. After you click Run, the startup transient’s time function will appear in seconds, showing an output voltage of approximately 5V.

Startup Transient analysis

Redesigning the Circuit

TINA and TINACloud’s Design Tool can automatically adjust circuit parameters to meet a new output voltage target. Let’s change the output voltage from 5V to 3.3V. Select Re-design this circuit from the Tools menu or double-click the text box on the circuit. In the dialog, simply change Vout to 3.3V and click Run. The Design Tool will automatically adjust components like the Rfb2 and Rload resistors to achieve the new output, providing an immediate diagram based on these changes. You can then run a more accurate numerical simulation to confirm the new voltage.

You can also run a more accurate simulation using the switching model. Just select the Transient Analysis Accurate link or check the “Use switching model” checkbox. This calculation takes longer (about a minute) but provides more detailed waveforms, including the ripple that the average model doesn’t show.

Startup transient fast analysis after redesigning the circuit
Startup transient accurate analysis after redesigning the circuit

2. Steady State and Ripple Voltage Analysis

Steady-state analysis examines a circuit’s behavior once all transients have settled. This is crucial for quickly determining ripple voltages. This method is particularly fast because it doesn’t require storing initial inductor and capacitor values. Using the same circuit file, let’s perform a transient analysis to see the ripple voltages and currents. A diagram of these values will appear after a brief calculation.

Steady state analysis

TINA and TINACloud can also quickly simulate how a DC-DC converter responds to sudden changes in either input voltage or load current. These are known as line stepping and load stepping, respectively.

3. Line Step Analysis

To see how the circuit responds to an input voltage change, click the “Line Step Analysis Fast” link. Within a few seconds, a diagram of the circuit’s response, including the full ripple voltage, will appear.

Line step fast analysis
Line step accurate analysis

4. Load Step Analysis

Similarly, to see the circuit’s response to a load current change, click the “Load Step Analysis Fast” link. The diagram will appear almost instantly. You can also run a more accurate, switching-mode version of this analysis by checking the “Use switching model” box in the transient dialog.

Load step fast analysis
Load step accurate analysis

5. AC Analysis

The built-in average models also enable fast and accurate AC analysis. Simply click the AC Transfer Characteristic link or select AC Analysis from the menu. This will display the AC Bode diagram of the loop gain.

AC Bode diagram (using fast analysis)
AC Bode diagram (using accurate analysis)

6. Efficiency Analysis

Additionally, TINA and TINACloud can quickly calculate and plot efficiency as a function of time and load current. By clicking the “Efficiency Analysis Fast” link, you can get a diagram showing efficiency versus time. By switching to the TR XY Plot Tab, you can also view efficiency as a function of output or load current.

Efficiency as a function of time
Efficiency as a function of Output or Load current

Conclusion

TINA and TINACloud provide a comprehensive and efficient platform for analyzing all the key characteristics of a synchronous step-down regulator like the LT8609. Its built-in average models and advanced solvers make it easy to quickly get accurate results for various analyses, including transient, ripple, line/load step, AC, and efficiency.

Click here to watch our video.

You can learn more about TINACloud here: www.tinacloud.com

You can learn more about TINA here: www.tina.com

TINA installation on macOS

TINA installation on macOS

Installing and Running TINA on macOS

Our tutorials (UK version, US version) show you how to install and run the TINA software on a macOS system. Follow these steps:

  1. Download the installer: Download the setup file using the link provided in your email.
  2. Unzip the archive: Use Finder to locate the downloaded file and unzip the archive. Some web browsers may do this automatically.
  3. Install the software: Double-click the installation package to begin the installation.
  4. Launch the application: After installation, go to the Applications folder in Finder and launch TINA.
  5. Complete the setup: The program will download additional files and install the main modules and the AI Assistant.
  6. Start TINA: Once the setup is complete, the TINA launcher will open. Double-click the TINA icon to start the program.

Registering and Authorizing TINA

To unlock the full version of the software, you’ll need to authorize it with your order number.

  1. Find your order number: Copy the order number from your order confirmation email.
  2. Authorize the software: In TINA, click the Authorize button.
  3. Enter the order number: Paste your order number into the authorization window and click OK.

After this initial setup, you can launch the application directly from the Applications folder in Finder.

Important Note on AI Assistant:To use the AI Assistant feature, you must have the AI software Ollama installed on your system beforehand.

TINA v15 on macOS: Practical Examples

In the following sections, we will use practical examples to demonstrate how to use TINA v15 on macOS, covering:

  • Transient Analysis
The transient response appears in the Diagram Window of TINA.
The transient response appears in the Diagram Window of TINA.
  • PCB Designer
Observing the design in the 3D viewer within the PCB Designer
  • Using TINA’s AI Assistant
Checking the output voltage by using transient analysis
Asking the AI Assistant to redesign the circuit to achieve an output voltage of 6V.
The output voltage is 6V and the changed components are selected in red.

Click here (UK version, US version) to watch our videos.

You can learn more about TINA here: www.tina.com

You can learn more about TINACloud here: www.tinacloud.com

Linux installation of TINA on openSUSE

Linux installation of TINA on openSUSE
This video will guide you through:
  • Installing Wine on SUSE Linux 
  • Installing TINA v15 on SUSE Linux 15.6
  • Operating TINA v15 on SUSE Linux 15.6

TINA, a Windows-based software, runs seamlessly on Linux by utilizing Wine, a compatibility layer. You can easily install it on SUSE Linux using the YaST Software Manager.

How to Install Wine on SUSE Linux?

To run TINA on Linux, Wine is essential. We recommend using Wine version 9 or later.

Here are the main installation steps:

  1. Launch YaST Software Manager: YaST2 (Yet another Setup Tool) is a powerful and user-friendly system administration tool for openSUSE and SUSE Linux, available with both graphical and text interfaces.
  2. Search for “wine”: Use the search function within YaST to find the Wine package.
  3. Select “wine” for installation: Check the box next to the “wine” package.
  4. Accept and install: Click “Accept” to begin the installation.
  5. Verify installation: After the process completes, confirm a successful installation in your Terminal.
  6. Configure Wine: Launch winecfg to set your preferred font size for optimal display.
  7. Start TINA setup: Once Wine is configured, you can proceed with the TINA setup.
How to install TINA v15 on SUSE Linux 15.6?

Up next, we’ll guide you through the installation of TINA v15 on SUSE Linux 15.6:

  • Download the setup ZIP file.
  • Execute the setup program and allow it to download all necessary components.
  • Proceed with the installation steps as prompted.
How TINA v15 Operates on SUSE Linux 15.6?

In conclusion, we’ll demonstrate TINA v15’s functionality on SUSE Linux through practical examples, including:

  1. Transient Analysis
  2. PCB Designer and Interactive simulation
  3. Using TINA’s AI Assistant

PCB Designer and Interactive simulation

For more detailed instructions on running TINA on Linux, please refer to our comprehensive guide: TINA Installation Guide for Linux.

Click here to watch our video.

Content of the video:

00:15 How to install Wine on SUSE Linux?

01:18 How to install TINA v15 on SUSE Linux 15.6?

02:17 How TINA v15 operates on SUSE Linux 15.6?

You can learn more about TINA here: www.tina.com

You can learn more about TINACloud here: www.tinacloud.com

Creating a Quiz using AI and Creating step-by-step solution of simple DC/AC circuits with TINA

Creating a Quiz using AI and Creating step-by-step solution of simple DC/AC circuits with TINA


Creating a quiz using the Hartley Oscillator circuit in TINA

This video covers how to create a quiz using the Hartley Oscillator circuit in TINA.

TINA’s AI assists you in generating quizzes for any circuit. Simply provide the circuit’s name if it’s well-known, or add a title and description for circuits that are less familiar. The AI analyzes your request and then provides a detailed summary of your learning progress.
Remember that questions are randomized, so you’ll likely face different questions even when using the same circuit.

Once you’ve answered five questions, you’ll be asked by the TINA AI to either retake or stop the test.

Creating step-by-step solution of simple DC/AC circuits

This video demonstrates step-by-step solutions for simple DC/AC circuits.

You’ll discover how TINA’s AI-powered analysis employs fundamental circuit theory to generate exact analytical results, perfectly aligning with the numerical outputs from TINA’s interactive DC analysis tool.


Our First Example: DC Circuit Analysis

First, we’ll analyze a circuit consisting of four resistors, a voltage source, and a voltmeter. We’ll use both AI and numerical simulation. After adjusting component values as needed, the circuit will be ready. We’ll then instruct the AI to “Calculate the voltage on R2.” The detailed analytical solution will immediately appear in the AI Assistant Window. We’ll compare this with the numerical simulation, confirming the results are identical. As an alternative, we can also have the AI “Calculate the voltage displayed by the Voltmeter.”

Our Second Example: Complex Circuits with Superposition

Next, we’ll analyze a more complex circuit with two sources. We’ll add a current source to our current setup. Our request to the AI will be: “Calculate the VM1 voltage.”

Here, the AI produces the analytical solution using the superposition method, calculating the effect of each source independently. Initially, the current source is considered while the voltage source is short-circuited. Then, the voltage source’s effect is determined, with the IS1 Current Source replaced by an open circuit.

Summing the results from these individual superposition runs yields the final VM1 voltage. We’ll conclude by comparing this result again with the numerical simulation.

TINA’s AI-powered analysis, using fundamental circuit theory, delivers results that precisely match numerical simulations, provided by the interactive DC analysis tool of TINA.

Click here to watch our video.

You can learn more about TINA here: www.tina.com

You can learn more about TINACloud here: www.tinacloud.com

Creating a Quiz using AI and Creating step-by-step solution of simple DC/AC circuits with TINACloud

Creating a Quiz using AI and Creating step-by-step solution of simple DC/AC circuits with TINACloud

Creating a Quiz using AI

This video demonstrates how TINACloud’s AI can assist in creating interactive quizzes for any circuit. For well-known circuits, simply provide the name; for others, a title and description will suffice. The AI analyzes your request and summarizes your learning progress.

Below, we outline the steps for taking a quiz in TINACloud. Please note that questions are randomly generated, so attempting the same circuit may result in different questions.

First, we instruct TINACloud’s AI to load a Hartley oscillator circuit. Once the circuit is loaded, we’ll enter “Create a Quiz” in the AI Assistant window. The quiz will consist of five questions. Upon completion of these questions, an evaluation of the session will be provided.

Creating a quiz with TINACloud’s AI

Creating step-by-step solution of simple DC/AC circuits

This video demonstrates how TINACloud’s AI-powered analysis uses fundamental circuit theory to derive step-by-step exact analytical results that precisely match the numerical results of TINACloud’s interactive DC analysis tool.

First, we’ll build a circuit consisting of four resistors, a voltage source, and a voltmeter. After adjusting component values, we’ll use TINACloud’s AI to calculate the voltage across R2. The detailed analytical solution will appear in the AI Assistant Window, and we’ll compare it to the numerical simulation to show they are identical. We’ll also have the AI calculate the voltage displayed by the voltmeter.

Calculating the voltage on R2 using AI and
Comparing the result with the numerical simulation


Next, we’ll tackle a more complex circuit with two sources by adding a current source to our existing circuit and calculating the VM1 voltage. For this, the AI will use the superposition method, analyzing the effect of each source separately. This involves:

  • Considering the current source while replacing the voltage source with a short circuit.

Processing Generator IS1

Processing Generator IS1
  • Considering the voltage source while replacing the current source with an open circuit.
Processing Generator VS1

Finally, we’ll compare the AI’s analytical result with TINACloud’s numerical simulation by pressing the DC button.

This will again confirm that TINACloud’s AI-powered analysis, using fundamental circuit theory, delivers results that precisely match numerical simulations, provided by the interactive DC analysis tool of TINACloud.

Click here to watch our video.

You can learn more about TINACloud here: www.tinacloud.com

You can learn more about TINA here: www.tina.com