Weewooday Mini 5V DC-DC Buck Converter Module User Manual

1. Introduction

This manual provides instructions for the Weewooday Mini 5V DC-DC Buck Converter Module. This module is designed to efficiently reduce a higher DC input voltage to a stable 5V output. It features both adjustable and fixed output voltage options, high conversion efficiency, and a compact size, making it suitable for various electronic projects requiring a stable 5V power supply.

Key Features:

Input Voltage Range: DC 4.5V - 24V
Output Voltage: Adjustable from 0.8V - 17V, or fixed outputs (1.8V, 2.5V, 3.3V, 5V, 9V, 12V) selectable via soldering.
Output Current: Up to 3A (cooling may be required for full load).
High Efficiency: Up to 97.5% conversion efficiency.
Compact Design: Ultra-small size for easy integration.
Enable Function: Control the module's operation with a low electric level to stop working.
Protection: Output short-circuit protection (avoid prolonged short-circuits).

Weewooday Mini 5V DC-DC Buck Converter Module construction

Figure 1: Overview of the Weewooday Mini 5V DC-DC Buck Converter Module, highlighting its compact construction and components.

2. Setup and Wiring

Proper wiring is essential for the safe and correct operation of the buck converter module. Refer to the diagrams below for connection points and voltage selection methods.

2.1. Connection Points

Weewooday Mini 5V DC-DC Buck Converter Module wiring diagram

Figure 2: Connection points on the buck converter module.

IN+: Positive input voltage (DC 4.5V - 24V).
GND: Common ground for both input and output. Connect both input negative and output negative to this one pin.
VO+: Positive output voltage (adjustable or fixed).
EN (Enable Port): This port controls the module's operation. A high electric level (2-5V) enables operation, while a low electric level (0V) stops it. If not used for external control, it can be left unconnected, as the module defaults to working mode. Warning: Do not connect the EN pin as a ground for your input voltage, as this will cause a short circuit.

2.2. Voltage Selection

The module offers both adjustable and fixed output voltage options. By default, the potentiometer on the board is used for adjustable voltage output. To use a fixed output voltage, a modification is required.

Adjustable Output (Default): The potentiometer on the top of the chip is used to adjust the output voltage. Connect the input voltage, then use a voltmeter to measure the output voltage at VO+ and GND. Rotate the potentiometer to achieve the desired voltage between 0.8V and 17V. Ensure your desired output voltage is always lower than your input voltage.
Fixed Output: If a specific fixed voltage (1.8V, 2.5V, 3.3V, 5V, 9V, 12V) is desired, you must first disable the adjustable potentiometer.
- Step 1: Carefully cut the circuit trace on the ADJ jumper pad located on the back of the board. This trace is typically under a green shielding. An X-Acto knife can be used for this. Ensure the connection is completely severed.
- Step 2: Solder the pad corresponding to your desired fixed voltage (e.g., 5V) on the back of the board. This will activate the fixed voltage output.

Weewooday Mini 5V DC-DC Buck Converter Module fixed voltage selection

Figure 3: Instructions for selecting fixed output voltage by cutting the ADJ trace and soldering the desired voltage pad.

3. Operating Instructions

Once the module is correctly wired and the desired output voltage is set, it is ready for operation.

Power On: Apply the DC input voltage (4.5V - 24V) to the IN+ and GND terminals.
Output Monitoring: Verify the output voltage at the VO+ and GND terminals using a voltmeter before connecting your load.
Load Connection: Connect your device or circuit requiring 5V to the VO+ and GND terminals. Ensure the current draw does not exceed 3A.
Cooling: For continuous operation at or near the maximum 3A output current, it is recommended to enhance cooling (e.g., by adding a heatsink or ensuring adequate airflow) to prevent overheating and maintain optimal performance. The module's operating temperature range is -40°C to +85°C.
Enable Function: If using the EN port, apply a high electric level (2-5V) to enable the module or a low electric level (0V) to disable it.

Video 1: An overview of the 5V Regulator Module, demonstrating its physical appearance and potential applications.

Weewooday Mini 5V DC-DC Buck Converter Module connected to a power supply

Figure 4: The buck converter module connected to a laboratory power supply for testing and operation.

4. Maintenance

The Weewooday Mini 5V DC-DC Buck Converter Module is designed for reliable operation with minimal maintenance. Follow these guidelines to ensure longevity:

Keep Clean: Ensure the module is free from dust, dirt, and moisture. Use a soft, dry brush or compressed air for cleaning if necessary.
Environmental Conditions: Operate the module within its specified temperature range (-40°C to +85°C) and avoid environments with high humidity or corrosive substances.
Secure Connections: Periodically check all soldered connections to ensure they are secure and free from corrosion or cold solder joints.
Overload Prevention: Avoid exceeding the maximum output current of 3A to prevent damage to the module. If the module becomes excessively hot, reduce the load or improve cooling.
Physical Protection: Consider enclosing the module in a protective casing or using adhesive-filled heat shrink tubing to protect it from physical damage and environmental factors, especially after setting the potentiometer.

5. Troubleshooting

If you encounter issues with your buck converter module, consider the following troubleshooting steps:

Problem	Possible Cause	Solution
No output voltage or incorrect voltage.	Incorrect wiring (IN+, VO+, GND). Input voltage outside 4.5V-24V range. Potentiometer not adjusted correctly (for adjustable output). ADJ trace not properly cut or fixed voltage pad not soldered (for fixed output). EN pin incorrectly connected or at low level.	Double-check all wiring connections against Figure 2. Ensure GND is common for input and output. Verify input voltage is within the specified range. Adjust the potentiometer slowly while monitoring output with a voltmeter. Review fixed voltage selection steps (Figure 3). Ensure the ADJ trace is fully cut and the correct pad is soldered. Ensure EN pin is either left unconnected or connected to a high electric level (2-5V) if external control is desired.
Module gets excessively hot.	Output current exceeds 3A. Insufficient cooling. Input voltage too high for the load.	Reduce the load current. Add a heatsink to the main IC or ensure better airflow around the module. Ensure the input voltage is not excessively high if the output current is also high, as this increases power dissipation.
Module fails immediately upon power-up (e.g., smokes, short circuits).	Reverse polarity on input. Short circuit on output. Incorrect wiring of EN pin (e.g., connected to ground). Defective module.	Always double-check input polarity before applying power. The module does not have output reverse connection protection. Ensure no short circuits exist on the output before connecting a load. Verify EN pin connection. It should not be connected to ground unless intentionally disabling the module. If all wiring is correct and the issue persists, the module may be defective.

6. Specifications

Detailed technical specifications for the Weewooday Mini 5V DC-DC Buck Converter Module:

Parameter	Value
Input Voltage	DC 4.5V - 24V
Output Voltage	Adjustable: 0.8V - 17V Fixed: 1.8V, 2.5V, 3.3V, 5V, 9V, 12V (selectable)
Output Current	3A max (with enhanced cooling)
Conversion Efficiency	Up to 97.5% (e.g., 6.5V to 5V, 0.7A)
Operating Frequency	500KHz
Output Ripple	20 mV (12V to 5V, 3A, 20M width)
Output Over-voltage Protection	No
Temperature Rising (Full Load)	40°C
Static Current	0.85mA
Voltage Adjustment Rate	-0.5%, 0.5%
Dynamic Response Speed	5% 200uS
Output Short-circuit Protection	Yes (avoid prolonged short-circuits)
Output Reverse Connection Protection	No
Wiring Method	Soldering
Output Method	Soldering or pins
Welding Hole Spacing	2.54 mm
Dimensions (L x W x H)	20 x 11 x 5 mm (approx. 0.78 x 0.43 x 0.19 inches)
Item Weight	0.8 ounces

Weewooday Mini 5V DC-DC Buck Converter Module dimensions

Figure 5: Physical dimensions of the buck converter module.

7. Package Contents

The package includes:

10 x Mini 5V Regulator Modules

Weewooday Weewooday-820