Fairchild TinyCalc service manual

www.fairchildsemi.com

TinyCalc™ User’s Guide (Excel® 07 Version)

Introduction

TinyCalc™ is a Microsoft® Excel®-based calculator created to simplify the design of TinyBuck™-based regulators.
TinyBuck™ products are integrated synchronous buck regulators with one high-side and one low-side MOSFET and a
controller / driver integrated in one 5x6mm molded leadless package (MLP).

The last digit in the part number signifies the current rating of the product. This calculator covers designs with FAN2103,
FAN2106, FAN2108, FAN2110, FAN21SV04, and FAN21SV06 regulators. Regulators with SV in the part numbers have a
built-in 5V regulator.

This document describes how to configure Excel 07 so this calculator can work without errors. This guide explains how to use
the TinyCalc™ calculator to choose external components for designs once the input and output conditions are provided.

Video Instructions

If you would prefer to watch an online video, click on the following link: “TinyCalc Setup Video”

Before Opening TinyCalc™

Add-in installation and Macro security selections must be set up
before opening TinyCalc™.

Check for Installed Add-in(s)

1. Open a new (blank) Excel

worksheet.

2. Click on the Windows icon

at the top left.

3. This opens up a pop-up

window (at right).

4. Click on the Excel Options

button at the bottom of this
dialog box which opens the
Excel Options window.

5. Click on the Add-Ins tab on

the left side of Excel Options
window. This lists all the
Add-ins available.

6. Click on the drop-down

window next to Manage: at
the left bottom, select Excel
Add-ins, and then click on
the Go... button next to it.

7. This opens the Add-Ins

dialog box.

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
Rev. 1.0.2 • 8/31/11

AN-8022 APPLICATION NOTE

8. Select Analysis Toolpak and Analysis Toolpak – VBA. Disregard any

other add-ins.

9. Click OK and return to the new worksheet.

Note: If these two add-ins aren’t available in the Excel installation, it is

necessary to install the complete version of Excel.

Set Macro Security to Medium

TinyCalc™ works by embedding calculations as macros. Excel must be able
to run these macros for the application to function, but macros are considered
a security risk. Therefore, to run the macros, it is necessary to set your security
to medium (vs. high). With the new (blank) worksheet open, follow these steps
to set the macro security:

1.

Click the Windows icon located at the top left of the screen.

2.

Click on the Excel
Options button at the
bottom right of the
window.

3.

Select Trust Center
in the left side of
Excel options window

4.

Click on the Trust
Center Settings...
button at the right.

5.

Select the Macro
Settings in the left
pane of the Trust
Center window.

6.

Select the option:
Enable all macros
(which
opens all
files with
macros)
OR

Disable all
macros
with
notification

(which
prompts
each time a
file with
macros is opened).

7.

Click OK and click OK again on the last window open. This returns to the open blank sheet.

8.

Close the blank worksheet.

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
Rev. 1.0.2 • 8/31/11 2

AN-8022 APPLICATION NOTE

Working with TinyCalc™

1. Close any open Excel workbooks or worksheets.

2. Open the TinyCalc™ file delivered with this user guide. (The file name might change based on the revision – go to the

website to get the latest version of the calculator.)

3. If macros are enabled, the file opens without any warning.

Skip to step 7.

4. If macros are disabled with notification, the file opens with a

security warning.

5. Click on the Options… button.

6. Select the option Trust all documents from this publisher and click OK. This closes the security alert and allows the

TinyCalc™ file to open.

7. When prompted to accept Fairchild’s terms and

conditions to use TinyCalc™, click the I Agree button.

8. In the Select Regular dialog box, select the regulator for your circuit design from the drop-down list and click OK.

9. Click OK to confirm the selection.

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
Rev. 1.0.2 • 8/31/11 3

AN-8022 APPLICATION NOTE

TinyCalc™ User Interface

The figure below is the “Front Page.” The numbers from 1 to 7 indicate the order of the steps involved in going through a
design. Once you are familiar with this calculator, you can skip to steps as needed by clicking on the appropriate button.

Clicking on the Welcome / Help / Design Procedure button opens the following dialog box. It is intended to provide first­time users a brief description of the steps. It is recommended that you read this page when you use the calculator for the first
time. Click OK to return to the Front Page.

© 2010 Fairchild Semiconductor Corporation www.fairchildsemi.com
Rev. 1.0.2 • 8/31/11 4