Do you have an "automotive" application for your micro-controller or Raspberry-Pi project? Offer it an adapted power supply to the automotive world. We found what we were looking for our own projects :-)
You've probably already had these cigarette lighter converters in hand that offer USB 5 Volts plugs for your iPhone, iPad or other USB device.
They are usually very compact and claim to produce 1 or 2 amps. In principle it's enough for your Raspberry-Pi 2 but do you think that such a device will last for a long time ?!?!
It should be known that the electric circuit of a car, by nature, is infested with noise and parasites... likewise, you can face many untimely variations of voltage (sometimes about ten volts and more).
So we were looking for something more appropriated and found a DC-DC regulator of the "automotive" type that we finally found at Olimex.
Once this regulation board in hand, we quickly realize that it's technically much better suited to our needs for hacking in electronics. It's based on the LM2576 specifically designed for automotive applications.
- Input voltage: between 9 and 36VDC (min 15V if you want 12V output)
- Output voltage:
- Fixed by jumper to weld
- 5 Volts by default
- 12 Volts selectable (by unsoldering the jumper 5V_E and 5V_USE_E) located near one of the capacities.
- A real cooling circuit (via heat-sink and dissipation surface on the board)
- Immunization of noise produced by the power source (by design) I
- Power supply via:
- Jack socket (positive center)
- Terminal block (right next to the jack)
- Via USB-A
- JST-PH connector (battery type)
Be careful, this is not a LIPO battery charging circuit!
- A terminal block (USB connector side).
- Ideal for powering automotive applications -or- power projects from 12/24 volts batteries
- A 12V LED indicator (when the output voltage is 12V)
- A USB LED indicator (when the USB port is powered, just behind the USB socket)
- LM2576 regulator
- Type Step-Down (buck)
- Max output current 3A (LM2576 data sheet)
- Overheating protection.
- Max current protection.
- Schema of the board (pdf, Olimex)
- LM2576 data sheet (pdf, Texas Instrument)
- Board size: 82 x 46mm
- Max Height: 40mm
Produce 12V output
This board is configured to produce 5V output (default).
If you want to produce a 12V output voltage, you'll need to remove the weld point on the jumper 5V_E and 5V_USB_E.
We insist that it's important to remove the weld point on jumper 5V_USB_E when switching to 12V output voltage. Otherwise, a 12V voltage will be available on the USB socket, which will destroy the device you could accidentally connect it.