The latest tech to get the LED growing community all riled up has been dubbed “Quantum Boards” by the fine folk who designed them over at the Horticulture Lighting Group. These things have created quite a buzz across the usual forums that growers frequent, and for good reason. If you haven’t heard of them yet, you’re likely wondering what exactly a Quantum Board is and what’s so great about them.
What’s a Quantum Board?
HLG’s Quantum Board is a large circuit board that has hundreds of mid-power LEDs mounted to it. The LEDs are connected together in series to form strings, and these strings are then combined in parallel configurations to make them compatible with common high-powered constant current drivers like the HLG 80-H-C, 240H-C, or 320-H-C series.
The 2 models available right now are the QB304 and the QB288. The number in the model number refers to the number of diodes.
The Almighty Samsung LM561C LED
These boards are built around the impressive Samsung LM561C diode. Boasting efficacy approaching 200 lumens per watt at low power, these diodes are incredibly efficient. Typical forward voltage for each diode is ~2.7-2.8V at 65mA of current. Absolute maximum current is rated at 200mA per diode.
If you want to play with some values and see what kind of output you can get from these diodes, check out Samsung’s calculator.
What are the Advantages Over COBs?
Here’s the question most skeptics are asking – why should I go QB over COBs? Well, you can sort of think of each of these boards as one giant COB. A typical COB has hundreds of individual diodes mounted to its little board, packed very tightly together. There are hundreds of diodes in these QBs as well, but they’re spread much further apart. The principal of harnessing the power of several small lights to produce one powerful source of light is the same, but the QBs just do it on a larger scale.
The main advantages for QBs are:
- Thermal management is much simpler. The board can be mounted to a thin piece of aluminum with no active cooling and the diodes stay nice and cool.
- More uniform spread of light. Compared to a COB that blasts all of its light from a surface 1″ in diameter, these boards are producing even light over the span of a foot.
- Greater efficiency. At 50 watts, these boards are getting 180+ lumens per watt. Highly efficient COBs like the Cree CXB3590 average 160-170 lumens per watt at 50W.
What are the Disadvantages?
A few of the disadvantages I can think of are as follows:
- There’s currently only one supplier and right now they’re completely out of stock.
- These boards are more difficult to DIY than COBs are (if you want to build the actual board yourself).
- Though light spread is better than typical COB setups, overall intensity in some areas is bound to be lower.
- Cost. The price of COBs has really come down lately and even factoring the cost of a heat sink per COB, you could get 3 decent COBs for the same price as one QB with a heat sink.
It’s great to see manufacturers innovating and trying new things – these boards look really promising and I’m very excited to try this tech out. Since HLG was out of stock, last night I ordered 600 of these Samsung LM561C diodes from Digikey and I’m going to try and build something similar myself – we’ll see how it goes! Once I’ve had the opportunity to test these things out, I’ll be sure to share my results.
Edit 05/10/17: Here’s the link to my DIY Quantum Board Build!
Edit 06/04/17: HLG sent me one of each of their QB Kits to test. Check out my 3-part video review.