Project Hub /Basic Analog & Power Electronics/Power Supplies & Voltage Regulators/DC to DC Converter with Constant Current (CC) and Constant Voltage (CV) Control - Schematics, PCB, Parts List, and Working

DC to DC Converter with Constant Current (CC) and Constant Voltage (CV) Control - Schematics, PCB, Parts List, and Working

Intermediate

ANALOG / DISCRETE

₹1,500 – ₹5,000

6 – 12 Hours

Partial Kit

DC to DC Converter with Constant Current (CC) and Constant Voltage (CV) Control - Schematics, PCB, Parts List, and Working

A comprehensive guide on reverse engineering, building, and testing an XL4015 5A DC-DC buck converter module with constant current and constant voltage regulation.

Originally published on CircuitDigest

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

LM2596 Step Down DC-DC Buck Converter Rs. 99.00
10pcs - 220 ohm 1/4 W Resistor Set Rs. 39.00
10pcs 5mm RED Diffused Light Emitting Diodes - LEDs Set Rs. 39.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

This list includes a generic resistor set as a placeholder — it is not matched to the exact value or part number this circuit needs. The correct one is specified on the original source page linked above; check it before buying.

We don't carry yet: Voltage Regulator IC (7805 / LM317 / 1117)
LM35 / Analog Temp Sensor
Diodes (1N4007 / 1N4148 / Schottky / Zener)
Capacitors
Potentiometer / Trimpot
Thyristor / SCR / Triac / Varistor / Fuse
TL431 Programmable Reference

Browse all components

How It Works

This circuit is a step-down (buck) power supply featuring both constant voltage (CV) and constant current (CC) regulation modes, built around the XL4015 buck converter IC as the primary power switching element. The XL4015 rapidly switches the input voltage to control the output, working alongside an SS54 Schottky diode to provide a continuous current path when the internal switch turns off. Input and output filtering are managed by 470uF 35V electrolytic capacitors and smaller 10uF and 0.1uF ceramic capacitors to stabilize the DC rails and suppress high-frequency switching noise. A 78L05 voltage regulator steps down part of the circuit to supply a stable 5V reference rail, while the TL431 programmable reference provides precise voltage referencing for the control loops. Dual LM358 operational amplifiers monitor the output parameters, comparing feedback signals against thresholds set by the 10K ten-turn trim pots. Depending on the load conditions, the control circuitry dynamically shifts the regulator between maintaining a steady output voltage and limiting the maximum output current to a safe, user-defined threshold. Three 0805 LEDs driven through current-limiting resistors provide visual status indicators for operational states such as power-on, constant voltage mode, and constant current mode, with connections made easily accessible via screw terminals.

Why Build This

Design a custom, highly efficient adjustable bench power supply for testing undergraduate prototype circuits.

Fabricate a reliable multi-stage lithium battery charging circuit with precise current limiting to prevent overcharging.

Implement a dedicated constant-current LED driver to safely power high-intensity lighting arrays without thermal runaway.

Real-World Application

Lithium battery charging, adjustable bench power supplies, LED driving, and voltage regulation in electronic prototyping.

Skills You'll Learn

Switch-mode power supply design

Constant current and constant voltage regulation

Operational amplifier feedback control

Printed circuit board layout in Eagle PCB

Thermal management in power electronics

Safety Precautions

Ensure correct input polarity and check for thermal limits when operating near maximum current capacity.

Technology Tags

XL4015

BUCK CONVERTER

CC/CV REGULATION

PCB DESIGN

REVERSE ENGINEERING

POWER ELECTRONICS

PWM

Frequently Asked Questions

Why does this circuit need both constant voltage and constant current modes?

Constant voltage (CV) mode keeps the output steady regardless of load changes, while constant current (CC) mode prevents the output current from exceeding a safe limit, which is especially crucial for charging batteries and driving LEDs.

What is the role of the LM358 operational amplifiers in a power supply circuit?

The LM358 op-amps act as error amplifiers that monitor the output voltage and current, comparing them against reference values and adjusting the control loop to maintain stable regulation.

Why are ten-turn trim pots used instead of standard single-turn potentiometers?

Ten-turn trim pots offer much higher resolution, allowing you to fine-tune the output voltage and current limit with great precision.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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