# 3. Assembly and Reflow

## Assembly Time!

Now that you have deposited solder paste on your circuit, all that is left to do is place your components and reflow the solder on the board.

{% hint style="info" %}
We have a component staging print out that you can use to layout all your parts in the correct orientation before placing them on your board:
{% endhint %}

{% file src="/files/fmwBmW9NTU3OFa4hUwUT" %}

### Surface Mount Components

The circuit requires the following components that have been included with the voltage regulator kit:

* Linear regulator IC × 1
* Switching regulator IC × 1
* Blue LED × 2
* 330Ω resistors × 2
* 0.1µF capacitors × 2
* 100µF capacitors × 3
* 330µF capacitor × 1
* Diode × 1
* 330µH inductor × 1
* Wire connector × 6
* Battery Connector × 1
* 9V battery × 1

<figure><img src="/files/5WvVWu8ZmYTesSMEDscd" alt=""><figcaption></figcaption></figure>

Carefully place your components onto the corresponding pads, as shown in the board layout below.&#x20;

<figure><img src="/files/pbAnuNhh05fuIArSLe70" alt=""><figcaption></figcaption></figure>

{% hint style="success" %}
Use the tweezers included with the V-One to place components precisely.
{% endhint %}

Do not smear the solder paste when placing components. Once they are placed, press down gently so the components rest evenly on the pads.

<figure><img src="/files/hYXZA7Rz4laUjLKVtdQ7" alt=""><figcaption></figcaption></figure>

Both the LED and the Electrolytic Capacitors have a polarity. Remember to double-check that they are placed in the correct orientation before you solder them to the board. When in doubt, reference the circuit schematic shown above.

<div><figure><img src="/files/mJAfJ9PNOO42tLAo0oKu" alt=""><figcaption><p>LED Corner cutout indicates this components cathode side</p></figcaption></figure> <figure><img src="/files/aBmrjWf30tDn5zhFmZvy" alt=""><figcaption><p>The solid paint stripe indicates this components negative terminal</p></figcaption></figure></div>

<div><figure><img src="/files/ZDiShrJpDwads297hXBV" alt=""><figcaption><p>The solid paint stripe indicates this components negative terminal</p></figcaption></figure> <figure><img src="/files/bl0j5TavPra3fhNgyWBU" alt=""><figcaption><p>The solid stripe on this component indicates the cathode side</p></figcaption></figure></div>

<figure><img src="/files/Mc16ZmkmnXon2byPGXpy" alt=""><figcaption></figcaption></figure>

Once all of the surface mount device (SMD) components are placed, proceed to the **HEAT** step.

{% hint style="info" %}
Even though diodes are typically marked where the cathode is, there are of course exceptions to this rule. Because of this it is very important to carefully review the datasheet of every diode/LED that you plan to use in your future designs.
{% endhint %}

### Reflow

Now that all of the surface mount components are placed, the circuit is ready to be reflow soldered.

1. From the start menu, select the **HEAT** option.
2. Click the **REFLOW** tile.
3. Select the solder paste you're using, based on the lot name printed on the cartridge label.
4. Click **REFLOW** to start the process.

<figure><img src="/files/wMzKrTsdBYQUxOeQzloC" alt=""><figcaption></figcaption></figure>

{% hint style="danger" %}
The V-One gets hot while reflowing. Do not touch! Do not leave unattended while heating!
{% endhint %}

When the heating cycle finishes, the V-One will start glowing blue. This means the soldered PCB is safe to remove.

### The Result

Plug in the 9V battery and watch your circuit come alive. If everything is working, the LED will be lit, and you should be able to measure 5V from the output side of the board.

Both the top two and bottom two sets of pads will output 5 volts.&#x20;

You can use this circuit to provide a steady source of 5V power to other connecting boards, such as the pulse generator kit.

<figure><img src="/files/bCNeSGSxjicdKQuh3Zz2" alt=""><figcaption></figcaption></figure>

Congratulations, you have completed the Voltage Regulator circuit board!&#x20;

That concludes the tutorial. If you ran into any hiccups along the way, let us know at <support@voltera.io>.

As a reminder, this circuit is part of a set of circuits designed to work together in a series. Although this circuit operates normally on its own, we recommend completing the pulse generator circuit and the 99 decimal counter circuit for a well-rounded learning experience.

<table data-card-size="large" data-view="cards"><thead><tr><th align="center"></th><th data-hidden data-card-cover data-type="image">Cover image</th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td align="center"><strong>Pulse Generator Project</strong></td><td><a href="/files/hRJGipC0YrzVqMaiYD6Z">/files/hRJGipC0YrzVqMaiYD6Z</a></td><td><a href="/pages/CMJbbh8EJNr0Yvxoc50k">/pages/CMJbbh8EJNr0Yvxoc50k</a></td></tr><tr><td align="center"><strong>99 Decimal Counter Project</strong></td><td><a href="/files/nmTDZvEDto14rvWtO0J9">/files/nmTDZvEDto14rvWtO0J9</a></td><td><a href="/pages/EBVd2zlsyA4okCvegAeT">/pages/EBVd2zlsyA4okCvegAeT</a></td></tr></tbody></table>

<br>


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