The article is being published in collaboration with JLCPCB. They supply high quality PCBs at a very reasonable price. They also can provide SMT circuit assembly.

We thanks to our sponsor JLCPCB https://jlcpcb.com/RTA for sponsoring us PCBs for this project circuit.

Thanks To JLCPCB.

$2 for 1-4 Layer PCBs.

Get SMT Coupons: https://jlcpcb.com/RTA

In this project, we’ll teach you making a multiple power supply circuit. It is a very cheap and useful SMT project circuit. To make different type project, sometimes we need different type voltage. As like 3.3v, 5v, 9v and 12v. For this case, we need to use different, different power supply.

But using this small and cheap SMT circuit, you don’t need to use different power supply circuit.

To make this circuit, we use bridge power supply circuit formula, liner voltage regulator and a 12v (3 amp) transformer.

Component List -

To making this SMT multiple power supply circuit, we are using some SMD components. You can order your assembled SMT circuit form JLCPCB.

All components list have been given below –

  • Transformer – 12v
  •  Diode – 1N 4007 *4
  •  Resistor – 1 KΩ
  •  LED
  • Capacitor - 1000µf / 25v
  • Liner Voltage Regulator – 7812, 7809, 7805, 7803
  • Output Sockets

Liner Voltage Regulator Pin Out -

Liner voltage regulator IC is an integrated circuit used in a variety of timer. This 3 pin integrated IC 3 different pinout.

Its 3 legs pinout can be seen above.

  •  In
  • GND
  • Out

The specialty of this IC is that, this IC can output fixed voltage.

Feature -

  •  Highly efficient
  •  Heavy-duty
  •  Cost-efficient
  •  Short regulation times
  •  Small residual ripple
  •  Simple circuitry
  •  Small size
  •  Light weight
  •  Wide input voltage range
  •  Highly efficient
  •  DC supply
  •  Buffering in case of mains voltage breakdown
  •  Easy to regulate
  •  Wide input voltage range
  •  Low mains pollution
  •  Excellent regulation
  •  Low ripple and noise
  •  Fewer series regulating transistors
  •  Lower power dissipation
  •  Higher efficiency than linear types
  •  Low operational costs
  •  Smaller regulator heat sinks
  •  Smaller in size and weight (for high switching rate)

Hardware of SMT Project Circuit - 

To make this SMT multiple power supply power supply circuit, we might need some electronics component. JLCPCB has its own parts library. JLCPCB has 200k+ in stock components, 24 hours rapid SMT assembly. You can check SMT parts library here.

Schematics and PCB Design - 

The schematics of PCBs can be seen above.

Circuit Connection - Step 1

To make this SMT multiple power supply circuit, 1st we make a bridge connection with these 4 diode. Then connect diode positive leg with capacitor positive leg and connect diode negative leg with capacitor negative leg.

With this power supply, we also can use a power indicator led light. When the circuit receive power signal, then the led light glow. We utilize JLCPCB https://jlcpcb.com/RTA to printout our PCB.


Circuit Connection – Step 2

Since it is a multiple power supply circuit, for this we need to use liner voltage regulator IC. We connect all liner voltage regulator IC “GND” leg with capacitor negative leg and all Liner voltage regulator “IN” leg with capacitor positive leg.

Now, we just need output voltage.

Circuit Connection – Step 3

Now we just add 5 sockets with this circuit. In this 5 sockets, 1 socket will contain “GND” voltage and other sockets will contain DC 3, 5, 9 and 12 volt.

Our circuit is now, completely ready for use. Just plug-in transformer with input leg of PCB and use your needed voltage from this circuit.

Thanks to JLCPCB for offering us, this SMT PCB circuit.

Steps to Order PCBs from JLCPCB -

If you complete design of your PCBs, then it is time to order PCBs. To order best quality PCBs, just visit JLCPCB and click on the “QUOTE NOW” button.

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