LTE Arduino Hat Development Board

Basic Overview #

The LTE Arduino Hat Development Board is a fully integrated cellular communication shield that turns almost any standard Arduino board into a complete IoT device with real 4G LTE connectivity, 2G fallback, precise GPS/GLONASS positioning, voice call capability, and SMS functionality.

It is designed as a true “HAT”, meaning it is 100% pin-compatible with the Arduino Uno form factor and its derivatives. You simply align the headers and press it directly onto your Arduino — no soldering, no jumper wires, no level shifters required. This makes it compatible with a very wide range of official Arduino boards.

Supported Module List #

Arduino uno R3
Arduino uno R3 SMD
Arduino Zero
Arduino Yun Rev2
Arduino UNO Wi-Fi Rev2
Arduino UNO R4 Wi-Fi
Arduino uno R4 Minima
Arduino Leonardo

Feature List #

Module Features:

Quad-band: 850/900/1800/1900MHz/LTE-FDD B1/LTE-FDD B3…
AT Commands: Compliant with 3GPP TS 27.007, 3GPP TS 27.005 and Quectel enhanced AT commands3- TCP/UDP/HTTP/FTP/PPP
Jamming Detection
Audio
FOTA
Single SIM, Single Standby
GPS+GLONASS
QuecFast Fix

Development Board Resources #

Function Description #

The main component and interface placement of the Development board is shown in the following figure:

Quectel EC200U Arduino HAT annotated diagram

Top PCB silkscreen of Quectel EC200U LTE Cat 1 Arduino HAT (Ser.A V1.0)

Development Board Configuration #

The detailed assignment of the peripheral interfaces on the Development board is as follows:

NO.	Name	Silkscreen	Comment
1	USB Type-C Interface	–	–
2	Audio jack 3.5 mm	–	–
3	Sim card case	–	4FF SIM Card 12.3 × 8 mm
4	Manual boot	BOOT	Push button
5	Manual Reset	RESET	Push button
6	Serial jumper	HRDW/SW	You can switch between hardware and software by changing the jumper position
7	External BT/WIFI Antenna	BT	UFL ANTENNA
8	External GNSS Antenna	GNSS	UFL ANTENNA
9	External GSM Antenna	MAIN	UFL ANTENNA

The Development board has 3 functional indication LEDs, as follows:

STA: LED Connect STATUS
NET: LED Connect NET_STATUS
D1: Power indication LED

Development Board Dimensions #

Quectel EC200U Arduino HAT dimension diagram

The main pin placement of the development board is shown in the following figure:

Quectel EC200U LTE Cat 1 Arduino HAT color-coded pinout diagram

Quectel EC200U module pin mapping on Arduino HAT

💡

Tip

As shown in the image above, Arduino can communicate with the module in two ways: software UART and hardware UART.

Development Board Interfaces #

Power Header

NO.	Name	Silkscreen	Comment
8-Pin	NC	NC	–
8-Pin	IOREF	IOREF	This provides a logic reference voltage for shields that use it. It is connected to the 5V bus
8-Pin	RST	RST	Reset Arduino
8-Pin	3v3	3v3	3.3 V Arduino regulator – don’t connect to power the module
8-Pin	5v	5v	5 V Arduino regulator – Do not power the module from the Arduino, but the module can power the Arduino
8-Pin	GND	GND	Ground
8-Pin	GND	GND	Ground
8-Pin	Vin	Vin	This pin is used to power the Arduino Uno board using an external power source. The voltage should be within the range mentioned above

ADC Header

NO.	Name	Silkscreen
6-Pin	ADC0	A0
6-Pin	ADC1	A1
6-Pin	ADC2	A2
6-Pin	ADC3	A3
6-Pin	ADC4	A4
6-Pin	ADC5	A5

The Arduino Uno has 6 analog pins, which utilize ADC (Analog to Digital converter).
These pins serve as analog inputs but can also function as digital inputs or digital outputs.

Analog to Digital Conversion

ADC stands for Analog to Digital Converter. ADC is an electronic circuit used to convert analog signals into digital signals. This digital representation of analog signals allows the processor (which is a digital device) to measure the analog signal and use it through its operation.

Arduino Pins A0-A5 are capable of reading analog voltages. On Arduino the ADC has 10-bit resolution, meaning it can represent analog voltage by 1,024 digital levels. The ADC converts voltage into bits which the microprocessor can understand.

One common example of an ADC is Voice over IP (VoIP). Every smartphone has a microphone that converts sound waves (voice) into analog voltage. This goes through the device’s ADC, gets converted into digital data, which is transmitted to the receiving side over the internet.

Digital Header

NO.	Name	Silkscreen	Comment
18-Pin	PD0/TX	0	Serial Communication
18-Pin	PD1/RX	1	Serial Communication
18-Pin	PD2	2	–
18-Pin	PD3/PWM	3	–
18-Pin	PD4	4	–
18-Pin	PD5/PWM	5	–
18-Pin	PD6/PWM	6	–
18-Pin	PD7	7	–
18-Pin	PB0	8	–
18-Pin	PB1/PWM	9	–
18-Pin	PB2/PWM/SS	10	SPI Communication
18-Pin	PB3/PWM/MOSI	11
18-Pin	PB4/MISO	12
18-Pin	PB5/SCK	13
18-Pin	Ground	GND	–
18-Pin	AREF	AREF	–
18-Pin	PC4/SDA	SDA	I2C Communication
18-Pin	PC5/SCL	SCL	I2C Communication

Header 2*5

NO.	Name	Silkscreen	Comment
*25-Pin**	DBG-TX	TX	Digital output
*25-Pin**	DBG-RX	RX	Digital input
*25-Pin**	WAKEUP_IN	GPIO1	Digital input
*25-Pin**	AP_READY	GPIO2	Digital input
*25-Pin**	I2C_SDA	SDA	Open Drain
*25-Pin**	I2C_SCL	SCL	Open Drain
*25-Pin**	SPI_CLK	CLK	Digital output
*25-Pin**	SPI_DIN	DIN	Digital input
*25-Pin**	SPI_CS	CS	Digital output
*25-Pin**	SPI_DOUT	DOUT	Digital output

Getting Started Preparation #

Quectel EC200U Arduino HAT placed side-by-side with Arduino UNO

Suppose you want to make a call, send an SMS, or even get the location of a device in your project. There are many solutions available, and the Quectel modules are one of the good choices as a powerful platform for wireless communications. In this tutorial, we will show you how to connect the EC200 hat to an Arduino using the TinyGSM library and use it to send SMS messages and make voice calls.

Okay, before we dive into the coding part, let’s get the required components and libraries ready:

EC200 hat: This hat is fully compatible with Arduino and is pin-to-pin. No additional wiring is needed.
Software Serial Library: This library is used for the software serial communication between the Arduino and the EC200 hat.
Jumpers: You will need jumpers to place the EC200 hat on the Arduino and to set the UART mode to software mode.

Preparation steps:

Place the EC200 hat on the Arduino.
Set the UART switch to the software mode.
Configure the jumpers to the software mode.

Now that everything is ready, we can start coding and use the EC200 hat to send SMS messages and make voice calls.

📥

Download TinyGSM

Download

Quectel EC200U LTE Cat 4G Arduino HAT real working setup

Arduino IDE code screenshot for Quectel EC200U HAT

In next step downloading the library, we need to add it to the compiler.

(Like the image below).

TinyGSM-main.zip library download for Quectel EC200U Arduino HAT

Once the library has been added, go to File -> Examples > TinyGSM > smsandvoicecall to select that example.

Complete working Arduino sketch for Quectel EC200U using TinyGSM + SoftwareSerial – sends SMS and makes voice call

After opening the example, we need to make a few changes to the code:

In the first line, replace it with the following code:

#define TINY_GSM_MODEM_EC200

1	#define TINY_GSM_MODEM_EC200

In line 12, enter the number that you want the module to call.
In line 15, change:

SoftwareSerial SerialAT(2, 3); // RX, TX

1	SoftwareSerial SerialAT(2, 3); // RX, TX

to set the baud rate to 115200, since the default baud rate of the module is 115200

Fully working Arduino sketch for Quectel EC200U LTE Cat 1 HAT – sends SMS and makes voice call using TinyGSM + SoftwareSerial on pins 7 & 8 at 115200 baud

Important Note: If you encounter the following error while compiling other examples of this library or even this library itself:

Arduino IDE compilation error "TinyGSMClient.h: No such file or directory" – fixed by installing TinyGSM library

You need to search for and download the required libraries from this section. After downloading, a message indicating successful download and installation will be displayed in the output.

TinyGSM-main.zip download screen – required Arduino library for Quectel EC200U / EC200A / MC60 series 4G modules

If you have followed the above steps correctly, the code will compile and be ready to upload to the Arduino. According to the image below, enter the model and COM port to which the Arduino is connected, and click on the option marked with 3 in the image to start uploading the code.

Arduino IDE Tools menu – selecting correct COM port after connecting EC200U LTE Arduino shield via USB-C

Upon completion of the compilation, place a nano SIM card into the EC200 hat (the operator does not matter) and connect the antenna to the UFL connector on the board.

The power supply for the EC200 hat is 5V, which you can connect from the header pins or via the USB Type-C port.

A very important note is that your power supply must be able to provide a peak current of 1.5 amps for the EC200 hat; otherwise, the module will reset.

Following the completion of the above steps, open the Arduino Serial Monitor and set the baud rate to 115200. The Arduino and the EC200 hat will start communicating with each other via UART, and their messages will be visible on the Arduino’s serial port.

Arduino IDE Serial Monitor showing Quectel EC200U successfully registering to network, sending SMS and making voice call

Arduino IDE Serial Monitor configured for Quectel EC200U LTE Cat 1 HAT – 115200 baud rate and "New line" setting required to see AT commands and debug output

Complete working Arduino sketch for Quectel EC200U using TinyGSM + SoftwareSerial – sends SMS and makes voice call

Tutorial Code #

// This line of code specifies that the EC200 modem is being used, which uses AT commands similar to the M66
#define TINY_GSM_MODEM_EC200

// These two lines of code include the necessary libraries for working with the EC200 modem and using SoftwareSerial
#include 
#include 

// These three lines of code define the GPRS network access details. In this example, they are not needed as we are only sending SMS and making calls
const char apn[]  = "your_apn"; // Not needed for SMS/Call, only for GPRS
const char user[] = "";
const char pass[] = "";

// This line of code defines the destination phone number
const char phoneNumber[] = "+1234567890";

// This line of code defines the SoftwareSerial pins for communication with the modem
SoftwareSerial SerialAT(2, 3); // RX, TX

// This line of code creates an object of the TinyGsm class to work with the EC200 modem
TinyGsm modem(SerialAT);

void setup() {
  // This section of code initializes the modem. It first sets up the debug serial, then establishes communication with the modem. After that, it restarts the modem and waits for a network connection
  Serial.begin(115200);
  delay(10);
  SerialAT.begin(115200);
  delay(3000);
  Serial.println("Initializing modem...");
  modem.restart();  // or modem.init();

  // This line of code allows unlocking the SIM card with a PIN
  // modem.simUnlock("1234");
  // This section of code waits for a network connection
  Serial.print("Waiting for network...");
  if (!modem.waitForNetwork()) {
    Serial.println(" failed");
    while (true);
  }
  Serial.println(" connected");
  // This section of code sends an SMS with the message "Hello from EC200!" to the specified phone number
  Serial.println("Sending SMS...");
  if (modem.sendSMS(phoneNumber, "Hello from EC200!")) {
    Serial.println("SMS sent successfully!");
  } else {
    Serial.println("SMS failed to send.");
  }
  // This line of code creates a 5-second delay before making a phone call
  delay(5000);
  // This section of code makes a call to the same phone number and hangs up after 20 seconds
  Serial.print("Calling ");
  Serial.println(phoneNumber);
  modem.callNumber(phoneNumber);
  delay(20000);
  modem.callHangup();
  Serial.println("Call ended.");
}

// This function has no code written in it, as all operations are performed in the `setup()` function
void loop() {
}

// This line of code specifies that the EC200 modem is being used, which uses AT commands similar to the M66

#define TINY_GSM_MODEM_EC200

// These two lines of code include the necessary libraries for working with the EC200 modem and using SoftwareSerial

#include

// These three lines of code define the GPRS network access details. In this example, they are not needed as we are only sending SMS and making calls

const char apn[] = "your_apn"; // Not needed for SMS/Call, only for GPRS

const char user[] = "";

const char pass[] = "";

// This line of code defines the destination phone number

const char phoneNumber[] = "+1234567890";

// This line of code defines the SoftwareSerial pins for communication with the modem

SoftwareSerial SerialAT(2, 3); // RX, TX

// This line of code creates an object of the TinyGsm class to work with the EC200 modem

TinyGsm modem(SerialAT);

void setup() {

// This section of code initializes the modem. It first sets up the debug serial, then establishes communication with the modem. After that, it restarts the modem and waits for a network connection

Serial.begin(115200);

delay(10);

SerialAT.begin(115200);

delay(3000);

Serial.println("Initializing modem...");

modem.restart(); // or modem.init();

// This line of code allows unlocking the SIM card with a PIN

// modem.simUnlock("1234");

// This section of code waits for a network connection

Serial.print("Waiting for network...");

if (!modem.waitForNetwork()) {

Serial.println(" failed");

while (true);

}

Serial.println(" connected");

// This section of code sends an SMS with the message "Hello from EC200!" to the specified phone number

Serial.println("Sending SMS...");

if (modem.sendSMS(phoneNumber, "Hello from EC200!")) {

Serial.println("SMS sent successfully!");

} else {

Serial.println("SMS failed to send.");

}

// This line of code creates a 5-second delay before making a phone call

delay(5000);

// This section of code makes a call to the same phone number and hangs up after 20 seconds

Serial.print("Calling ");

Serial.println(phoneNumber);

modem.callNumber(phoneNumber);

delay(20000);

modem.callHangup();

Serial.println("Call ended.");

}

// This function has no code written in it, as all operations are performed in the `setup()` function

void loop() {

}

Downloads #

EC200 Arduino Hat Schmatic

FAQ #

What does digital mean?

Digital is a way of representing voltage in 1 bit: either 0 or 1. Digital pins on the Arduino are pins designed to be configured as inputs or outputs according to the needs of the user. Digital pins are either on or off. When ON they are in a HIGH voltage state of 5V and when OFF they are in a LOW voltage state of 0V.

On the Arduino, when the digital pins are configured as output, they are set to 0 or 5 volts.

When the digital pins are configured as input, the voltage is supplied from an external device. This voltage can vary between 0–5 volts which is converted into digital representation (0 or 1). To determine this, there are 2 thresholds:
• Below 0.8V – considered as 0.
• Above 2V – considered as 1.

When connecting a component to a digital pin, make sure that the logic levels match. If the voltage is in between the thresholds, the returning value will be undefined.

What is PWM?

In general, Pulse Width Modulation (PWM) is a modulation technique used to encode a message into a pulsing signal. A PWM is comprised of two key components: frequency and duty cycle. The PWM frequency dictates how long it takes to complete a single cycle (period) and how quickly the signal fluctuates from high to low. The duty cycle determines how long a signal stays high out of the total period. Duty cycle is represented in percentage.

In Arduino, the PWM enabled pins produce a constant frequency of ~500Hz, while the duty cycle changes according to the parameters set by the user. See the following illustration:

PWM duty cycle waveforms showing 0%, 25%, and 100% with period marked.
Period-labeled PWM signals at 0%, 25%, and 100% duty cycle.
PWM signals are used for speed control of DC motors, dimming LEDs and more.

What is Serial Communication?

Serial communication is used to exchange data between the Arduino board and another serial device such as computers, displays, sensors and more. Each Arduino board has at least one serial port. Serial communication occurs on digital pins 0 (RX) and 1 (TX) as well as via USB. Arduino supports serial communication through digital pins with the Software Serial Library as well. This allows the user to connect multiple serial-enabled devices and leave the main serial port available for the USB.

Software serial and hardware serial – Most microcontrollers have hardware designed to communicate with other serial devices. Software serial ports use a pin-change interrupt system to communicate. There is a built-in library for Software Serial communication. Software serial is used by the processor to simulate extra serial ports. The only drawback with software serial is that it requires more processing and cannot support the same high speeds as hardware serial.

SPI – SS/SCK/MISO/MOSI pins are the dedicated pins for SPI communication. They can be found on digital pins 10–13 of the Arduino Uno and on the ICSP headers.

What is SPI?

Serial Peripheral Interface (SPI) is a serial data protocol used by microcontrollers to communicate with one or more external devices in a bus-like connection. The SPI can also be used to connect 2 microcontrollers. On the SPI bus, there is always one device that is denoted as a Master device and all the rest as Slaves. In most cases, the microcontroller is the Master device. The SS (Slave Select) pin determines which device the Master is currently communicating with.

SPI enabled devices always have the following pins:
• MISO (Master in Slave out) – A line for sending data to the Master device
• MOSI (Master out Slave In) – The Master line for sending data to peripheral devices
• SCK (Serial Clock) – A clock signal generated by the Master device to synchronize data transmission.

I2C – SCL/SDA pins are the dedicated pins for I2C communication. On the Arduino Uno they are found on Analog pins A4 and A5.

What is I2C?

I2C is a communication protocol commonly referred to as the “I2C bus”. The I2C protocol was designed to enable communication between components on a single circuit board. With I2C there are 2 wires referred to as SCL and SDA.

• SCL is the clock line which is designed to synchronize data transfers.
• SDA is the line used to transmit data.

Each device on the I2C bus has a unique address, up to 255 devices can be connected on the same bus.

Aref – Reference voltage for the analog inputs.
Interrupt – INT0 and INT1. Arduino Uno has two external interrupt pins.
External Interrupt – An external interrupt is a system interrupt that occurs when outside interference is present. Interference can come from the user or other hardware devices in the network. Common uses for these interrupts in Arduino are reading the frequency a square wave generated by encoders or waking up the processor upon an external event.

Arduino has two forms of interrupt: External and Pin Change.
There are two external interrupt pins on the ATmega168/328 called INT0 and INT1. Both INT0 and INT1 are mapped to pins 2 and 3. In contrast, Pin Change interrupts can be activated on any of the pins.

What is the LTE Arduino HAT?

A full-featured Arduino shield (HAT) built around the Quectel EC200U series LTE Cat 1 module, offering 4G cellular + GNSS + Bluetooth/Wi-Fi scan in the exact Arduino UNO R3 pinout.

Which Arduino boards are officially supported?

• Arduino UNO R3 / R3 SMD
• Arduino UNO R4 Minima & Wi-Fi
• Arduino Leonardo
• Arduino Zero
• Arduino Yún Rev2
100% pin-compatible – just plug and play.

Can I power the module from Arduino’s 5V pin?

Absolutely not! The EC200U can draw up to 1.8–2 A peak current during transmission. Arduino’s regulator can only supply ~500 mA. Always power via USB-C or external 5 V / ≥2 A source.

How do I switch between Hardware and Software Serial?

Use the HRDW/SW jumper:
• HRDW → Arduino pins D0/D1 (Hardware Serial – fastest, recommended)
• SW → Any digital pins via SoftwareSerial (useful when USB debug is needed)

Is GNSS (GPS) supported?

Yes — EC200U has built-in GPS + GLONASS + BeiDou + Galileo. Dedicated U.FL connector for active antenna and 1PPS pin broken out.

Can I make voice calls and send SMS?

Yes — full circuit-switched voice and SMS support. 3.5 mm audio jack included for headset/mic. Perfect with TinyGSM examples.

How do I upload new firmware or enter EDL mode?

Hold the BOOT button while pressing RESET (or plug in USB-C while holding BOOT) → module enters Qualcomm EDL mode for QDLoader flashing.

What baud rate should I use?

Default is 115200 bps. Some firmwares use auto-baud — TinyGSM handles this automatically.

Which library is recommended for Arduino?

TinyGSM is the best choice — fully supports EC200U (use #define TINY_GSM_MODEM_EC200). Hundreds of ready examples for SMS, calls, MQTT, HTTP, GNSS, etc.

Is Bluetooth and Wi-Fi available?

EC200U supports Bluetooth 4.2 LE and Wi-Fi scan (passive). Dedicated U.FL connector for external BT/Wi-Fi antenna is provided.

What do the three LEDs indicate?

• STA: Module power & running
• NET: Network registration status
• D1: Power ON (5 V rail active)

Add to Cart – EC200U Arduino HAT Development Board

Add to Cart – EC25-E Arduino HAT Development Board

Updated on December 17, 2025

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