# Voltage Regulator

## 🛆 Brief description

A voltage regulator is always essential in electronic projects. It provides a constant, low-noise supply voltage. A regulator can only provide one supply voltage. On this board, all components require a supply voltage of 3.3V. Therefore, a single voltage regulator is implemented.

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## 🛆 Voltage Regulator Chip

The TPS7A02 is an ultra-small, ultra-low quiescent current, low dropout linear regulator (LDO) widely used in electronic applications. 

The device has very low power consumption (around 25nA), making it ideal for power management applications. In addition, this LDO can deliver up to 200mA, which is sufficient for the tracker's power requirements.

<figure><img src="/files/INiSvMgYUKjIPyuc3Ahc" alt="" width="320"><figcaption></figcaption></figure>

### Technological capabilities

| Features             | Description             |
| -------------------- | ----------------------- |
| Input Voltage Range  | From 1.5V to 5V         |
| Output Voltage Range | From 0.8V to 5V (fixed) |
| Output Accuracy      | 1.5% over temperature   |
| Current consumption  | \~25nA                  |
| Voltage Dropout      | 250mV at 200mA          |

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## 🛆 Hardware Integration

### Pin Configuration & Description

The TPS7A02 IC is available in two packages: 4-pin X2SON (1x1mm) or 5-pin SOT-23 (2.9x2.8mm). I chose the SOT-23 package because it's easier to debug if necessary. The voltage regulator is a critical component on a board. It's important to be able to replace it if necessary.&#x20;

The available pins are listed in the table below:

<table><thead><tr><th width="145">Pin Number</th><th width="145">Name</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>IN</td><td><p>Input Voltage Pin. </p><p>Voltage to regulate.</p></td></tr><tr><td>2</td><td>GND</td><td>GND</td></tr><tr><td>3</td><td>EN</td><td>Driving this pin to high enables the regulation voltage. Driving to a low logic state disables the device.</td></tr><tr><td>4</td><td>NC</td><td>No connect pin. This pin is not internally connected. Connect to ground or leave floating.</td></tr><tr><td>5</td><td>OUT</td><td>Regulated output pin.<br>Voltage regulated</td></tr></tbody></table>

### Kicad - Rooting

The voltage regulator chip is wired according to the data sheet (see page 26). A 1µF input and output is used for load transient response. Pin 4 is left floating and pin 3 is wired to the input voltage (voltage coming from the battery).

<figure><img src="/files/iIKJsoOuU7GOO4FF5eq0" alt=""><figcaption><p>Kicad Schematic | Voltage Regulator Stage</p></figcaption></figure>

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## 🛆 Documentation

{% embed url="<https://www.ti.com/product/TPS7A02>" fullWidth="false" %}
Web Site | Texas Instruments | TPS7A02
{% endembed %}

{% file src="/files/6QpIdPtSUmQoMDBjSJeg" %}
Datasheet | Voltage Regulator | TPS7A02
{% endfile %}


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