# Powering SMD 5050 strip via LM2596 DC/DC converter

I decided not to order / use the power supply typically sold with SMD 5050 kits.
I heard a lot of explosion stories regarding those dodgy stuff.

I want to make my own (power supply to drive SMD 5050.
Using: a DC adapter found at home hooked up to LM2596 converter.

Facts:

• From what I gather, LM2596 regulates the voltage AND can supply 1 to 2 amps of power safely (more requires heatsink?).

• A single SMD 5050 chip uses 0.24 w of power.

• SMD 5050's run on 12v.

My question:

• Is it safe to assume that I can connect any number of LED strip blocks (with each block having 3 LEDs each using 0.24w, therefore ~0.75w), as long as total amps do not exceed what LM2596 AND power adapter attached to it can supply (being max 2 amps)?

My calculation:

watt = amps x volts means each LED uses 0.02 amp.

So if I have 30 blocks == 90 LEDs.

90 * 0.02 = 0.6 amps.

• Would it work fine?

• And if I just connect a single block needing 0.02 amp, would it still work fine?

• What would happen if I connect more LEDs and exceed the amps LM2596 can provide?

I don't want my leds burning in day 2 and learn about this subject.

I'd very much appreciate it if all questions were answered.

Thank you!

LED strips work at \$12\, \mathrm{V}\$, but the individual chips do not. They are connected in groups of three with one series resistor. Voltage drop of one LED is around \$3.6\, \mathrm{V}\$, so the current is \$\dfrac{0.24}{3.6}\cong 65\, \mathrm{mA}\$. For 30 blocks, it is \$30\cdot 65 \cong 2\, \mathrm{A}\$.