> ## Documentation Index
> Fetch the complete documentation index at: https://learn.pcbcupid.com/llms.txt
> Use this file to discover all available pages before exploring further.

> The G-Mod Lithium Charger safely charges 1S (3.7V) and 2S (7.4V) lithium-ion batteries with adjustable current settings for portable projects.

# Lithium Charger

export const ShopHeader = ({title, url}) => <div style={{
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      Shop now
    </a>
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            3D VIEW
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<ShopHeader title="Lithium Battery Charger Module" url="https://shop.pcbcupid.com/product/gm014/" />

<ImgGallery images={[{url: "https://files.pcbcupid.com/Documentation/Boards/g-mod/Li-ion%20charging%20/lithium_charger_illustration.avif", label: "ILLUSTRATION", id: "illustrat"}]} />

A **lithium charger** is a versatile power management module used to safely charge either a single (1S) or double (2S) lithium-ion battery pack. It employs the Constant Current / Constant Voltage (CC/CV) method to ensure maximum battery life and safety. This module is ideal for robotics, portable electronics, and any application requiring reliable battery recharging.

<br />

\`

***

## ⚙️ Charging Mode Configuration

The module can be configured for two different battery types by modifying a hardware solder point on the board labeled **2S**.

### 1. Mode Selection

* **1S Mode (3.7V / 4.2V Full)**: Leave the **2S** solder point **OPEN** (default).
* **2S Mode (7.4V / 8.4V Full)**: **SHORT** (solder) the **2S** point to select 2S charging.

### 2. Input Voltage Requirements

To ensure proper charging, your input power supply must meet the following minimums:

* **1S Mode**: 5.0V – 18V DC input.
* **2S Mode**: 10V – 18V DC input (12V recommended).

***

## 🔌 Pin Configuration

* **IN+** – DC Power Input Positive
* **GND** – DC Power Input Ground
* **B+** – Battery Positive Terminal
* **B−** – Battery Negative Terminal
* **G** – Ground
* **NTC** – Temperature sensor input
* **LED+** – LED Positive (for external status)
* **CHR** – Charging status output (Red LED)
* **STB** – Standby / Full status output (Blue/Green LED)

***

## 🚀 Key Features

* **Dual Mode Support**: Charges 1S (3.7V) and 2S (7.4V) packs.
* **High Current Rating**: Supports up to **2A** default charging current.
* **Adjustable Current**: The charging current can be varied by changing the **current limiting resistors** on the board.
* **CC/CV Charging**: Automatic transition from constant current to constant voltage.
* **Status Monitoring**: Dedicated pins for external status LEDs.
* **Safety**: Includes overcharge protection and NTC temperature sensing support.

***

## 🛠️ Step 1: Hardware Required

1. G-MOD Lithium Charger Module (GM014)
2. Lithium-ion Battery:
   * **1S**: 3.7V Cell
   * **2S**: 7.4V Battery Pack
3. DC Power Supply (5V for 1S, 12V for 2S)
4. Connecting Wires
5. Screwdriver (for terminal connections)

***

## ⚡ Step 2: Circuit Connection

> \[!IMPORTANT]
> Always verify the **2S** solder point configuration before connecting your battery. Connecting a 1S battery while the board is in 2S mode will damage the battery.

![Lithium-Charger-Wiring](https://example.com/dummy-image-url-for-wiring.png)

***

## 📊 Step 3: Observe the Output

Once connected, the **CHR** pin will pull low to indicate charging is active. Once the battery reaches its target voltage (**4.2V for 1S** or **8.4V for 2S**), the **STB** pin will trigger to signal a full charge.

* **Current Limiting**: If you need to charge smaller batteries, replace the surface-mount current-sensing resistors to lower the 2A output to a safer level for your specific cells.