1. Introduction
This manual provides essential instructions for the safe and efficient operation of the DollaTek DC 24V to 12V Constant Current/Constant Voltage (CC CV) Step-Down Converter module. Please read this manual thoroughly before installation and use to ensure proper functionality and to prevent damage to the device or connected equipment.
2. Product Overview
The DollaTek DC-DC Step-Down Converter is a non-isolated module designed to convert a higher DC input voltage (7-32V) to a lower, adjustable DC output voltage (0.8-28V) with constant current and constant voltage capabilities. It is suitable for various applications requiring precise power regulation, such as LED drivers, battery charging, and power supply for electronic projects.
Figure 1: Top view of the DollaTek DC-DC Step-Down Converter module, showing the heatsinks, capacitors, inductor, and terminal blocks.
Figure 2: Angled view of the converter, highlighting the input/output terminals and adjustment potentiometers.
3. Setup and Connection
Follow these steps for proper setup and connection of the converter module:
- Input Connection: Connect your DC power source (7-32V) to the input terminals labeled 'IN+' (positive) and 'IN-' (negative). Ensure correct polarity.
- Output Connection: Connect your load or device to the output terminals labeled 'OUT+' (positive) and 'OUT-' (negative). Ensure correct polarity.
- Initial Adjustment (Voltage): Before connecting a load, power on the module. Use a voltmeter to measure the output voltage. Adjust the potentiometer located near the input terminals (CV potentiometer) clockwise to increase voltage or counter-clockwise to decrease it, until the desired output voltage is reached.
- Initial Adjustment (Current): For constant current applications (e.g., LED driving, battery charging), connect your load. Adjust the potentiometer located near the output terminals (CC potentiometer) to set the desired constant current limit. A multimeter in series with the load can be used to monitor the current.
- Cooling: For output currents exceeding 6A or if the power tube temperature rises above 65°C, an external cooling fan is required to prevent overheating and ensure stable operation.
Figure 3: Close-up view of the module, indicating the input and output screw terminals for wiring.
4. Operating Instructions
Once connected, the module operates as a step-down converter. The two potentiometers allow for precise control over the output characteristics:
- Voltage Adjustment (CV): The potentiometer closer to the input terminals controls the output voltage. Turn clockwise to increase voltage, counter-clockwise to decrease.
- Current Adjustment (CC): The potentiometer closer to the output terminals controls the constant current limit. Turn clockwise to increase the current limit, counter-clockwise to decrease. When the load current reaches this set limit, the module will operate in constant current mode.
Important Considerations:
- This module does not have input reverse polarity protection. Ensure correct input polarity to prevent damage.
- This module does not have output anti-backflow protection. If connecting to a battery, a diode may be required on the output to prevent current from flowing back into the module.
- The maximum output power is 300W. Do not exceed this limit.
5. Maintenance
The DollaTek DC-DC Converter module is designed for reliable operation with minimal maintenance. However, consider the following:
- Cooling: Regularly check the operating temperature, especially during high-load applications. If the power tube temperature consistently exceeds 65°C, ensure the cooling fan (if installed) is functioning correctly or consider adding one.
- Cleanliness: Keep the module free from dust and debris to ensure optimal heat dissipation and prevent short circuits.
- Connections: Periodically inspect all wiring connections to ensure they are secure and free from corrosion.
6. Troubleshooting
If you encounter issues with the module, perform the following checks:
- No Output Voltage: Verify the input voltage is within the 7-32V range. Check input and output wiring for correct polarity and secure connections. Ensure the voltage adjustment potentiometer (CV) is not set to its minimum.
- Incorrect Output Voltage/Current: Use a reliable multimeter to measure the output. Adjust the respective potentiometers (CV for voltage, CC for current) as described in the 'Operating Instructions' section.
- Overheating: Reduce the load or ensure adequate cooling is provided. The module may enter thermal shutdown if it becomes too hot.
- Unstable Output: Check for loose connections or excessive ripple on the input power supply. Ensure the load is not exceeding the module's maximum power rating.
7. Specifications
| Parameter | Value |
|---|---|
| Module Properties | Non-isolated step-down module, Constant Current & Constant Voltage (CC CV) |
| Input Voltage | DC 7-32V |
| Output Voltage | DC 0.8-28V (continuously adjustable) |
| Output Current | 12A MAX (requires cooling fan if power tube temp > 65°C) |
| Constant Current Range | 0.2-12A (continuously adjustable) |
| Current Indicator Threshold Voltage | 1V |
| Output Power | Max 300W |
| Conversion Efficiency | Up to approx. 95% |
| Output Ripple | Approx. 50mV (Input 24V, Output 12V 5A) |
| Operating Temperature | Industrial grade (-40°C to +85°C) |
| No-load Current | Typical 20mA |
| Load Regulation | ±1% (constant voltage) |
| Voltage Regulation | ±1% |
| Dynamic Response Speed | 5% 200uS |
| Input Reverse Polarity Protection | No |
| Output Anti-backflow Protection | No |
| Dimensions (L x W x H) | Approx. 65 x 47 x 23.5mm |
Figure 4: Dimensions of the DollaTek DC-DC Step-Down Converter module.
8. Warranty and Support
Specific warranty details and direct support contact information are not provided in the product data. For warranty claims or technical assistance, please refer to the retailer or vendor from whom the product was purchased.
