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The Complete Guide to Series and Parallel Circuits for LED Strip Lighting Project

The core of LED strip connection lies in its internal circuit logic. Series and parallel connections are two of the most basic circuit connection methods. Proper method selection guarantees even and bright lighting, whereas improper selection creates insufficient brightness or safety hazards.

This article will explain the differences between these two circuits in the simplest way, and tell you their advantages and disadvantages. If you understand the difference between circuits in series and parallel, you can avoid the hidden dangers of uneven voltage or single-point failures quickly, and this ensures more stable operation of the LED strip.

Basic Circuit Structure

1. Internal Series Structure

Let us take Group 1 as an example. It consists of 6 LED beads connected in series.

If any one of the LED beads fails, the entire series circuit breaks, and all 6 LED beads in Group 1 will turn off.

2. Parallel Connection Between Groups

Groups 1, 2, 3, and 4 are connected in parallel:

When Group 1 turns off due to the failure of its internal LED beads, Groups 2, 3, and 4 are completely unaffected and continue to emit light normally.

Similarly, Groups 5-8 and 9-12 have the same circuit structure.

3. The three LED strips in Groups A, B, and C are connected in series.

1. Similar to the basic series circuit structure described above, within each group (e.g., the 6 LEDs in group 1), the LEDs are connected in series. And within the same LED strip, groups 1, 2, 3, and 4 are connected in parallel. Similarly, groups 5-8 and groups 9-12 are also in basic parallel circuit.

2. The three LED strips A, B, and C in the diagram above are connected in parallel. As shown, groups A, B, and C are connected side-by-side at both ends of the power supply.

For more information about the connection, you can click on: How to Wire and Code WS2818 LED Strip on ESP8266 How to Wire and Code SK6812 RGBW LED Strips on Raspberry Pi.

Practical Application Forms of LED Strips

In actual purchased LED strips, you will rarely see pure series or pure parallel circuits. Instead, a combination of series and parallel is used, with the focus varying based on voltage.

The cutting unit of an LED strip directly determines its internal series and parallel circuit structure, which in turn affects the voltage selection (12V vs 24V) and the final performance.

The operating voltage of a single LED bead (taking 2835/5050 as an example) is typically 3V.

12V LED Strip: 3 LEDs + 1 resistor = 1 unit

3 LEDs in series: 3 × 3.2 V = 9.6 V

Residual Voltage: 12 V − 9.6 V = 2.4 V

This 2.4V is handled by the current-limiting resistor and dissipated as heat.

Parallel Connection: The entire LED strip is composed of hundreds or thousands of “3-series units” connected in parallel.

24V LED Strip: 6 LEDs + 2 resistors = 1 unit

6 LEDs in series: 6 × 3.2 V = 19.2 V

Residual voltage: 24 V − 19.2 V = 4.8 V

This is borne by the current-limiting resistor.

Cutting unit: 6 LEDs per cut.

Parallel connection: The entire LED strip is composed of hundreds or thousands of “6-series units” connected in parallel.

Whether it’s 12V or 24V, the overall structure of the LED strip is a parallel connection. The so-called “series wiring” refers to connecting multiple LED strip segments end to end during external installation, while the internal microstructure is always “series first, then parallel“.

Learn more about 24v led strip: SPI 24V Individually Addressable LED Strip: WS2815 vs SK6812 vs GS8208

Pros and Cons of Series and Parallel

Pros and Cons of External Series

Advantages	Disadvantages
1. Simple WiringIt installs quickly and saves a lot of cable.	1. Voltage Drop If you connect more strips in a row, the total resistance increases greatly. This will result in uneven brightness.
2. Smooth Signal Transmission Works best with programmable strips. Since the data moves in a simple chain, it can skip the complicated distributors.	2. Risk of Overheating If you use wires that are too thin or connect too many strips, the high current will cause the connections to overheat due to resistance.
3. Clean InstallationThis cuts down on visible power cables, and it makes the appearance cleaner.	6. Overpressure risk If you use a high-voltage powersupply for a low-voltage strip to overcome voltage drop, the rear sections may receive excessive voltage and fail immediately.

Pros and Cons of External Parallel

Pros	Cons
Uniform Brightness Each led strip draws its full voltage directly from the power supply to achieve consistent lighting.	Complex Wiring This setup requires multiple cables and distribution boxes, which leads to high labor costs and makes the concealment work very demanding.
Flexible Control You can easily add separate switches or controllers to each section, which allow you to control different lighting areas independently.	Higher Material Cost This setup requires thicker main cables to carry the total current, which also increases the overall volume of branch wiring.
Easy to Expand You can add new sections anytime, as long as your power supply and main cable can handle the extra load. Each new section works independently without affecting the others.	Space Issues Junction boxes and split points need plenty of room, but this is often impossible in narrow light channels.

The 48V LED strips reduces the current of the same power by 75%, which almost eliminate voltage drop loss, and establish the series scheme as the preferred choice for long-distance lighting. Here are three major advantages: fast installation, simple wiring, and low cost. If you want to know more about the 48V LED strips, you can check out this blog: 48V Long Run LED Strip 35m/40m/65m Without Extra Power Injection

LEDSuntech

LED Strip Manufacturer & Supplier