Hi guys,
So I've designed the following:
1. Power up circuit using Car's battery, ground and ignition signals. Pine64 will be powered on as long as the key is in the ignition and the engine is on.
2. 4 channel (FL, FR, RL and RR) analog audio amplifier (each channel delivers 50W).
3. Sound processor with 3 band equalizer (mid, bass, treble).
Currently I am working on a layout (not a layout guy - if someone has experience with KiCad, please let me know I could use some help). I will put all of these on one board (POT) that will plug in on top of Pine64.
I plan to have this completed in the next couple of weeks. I will keep you posted on the progress.
From the car, you have Battery, Ground, and Ignition (Accessory) wires (signals).
Pine64 has DC_in on one of the connectors, which is I believe 5V. You would have to connect the two.
How:
Car's alternator will produce around 13.6V, so you will need a step down converter, to get to 5V. Ideal amperage for Pine64 (according to Pine64 folks) is 2A.
So, look for the converter with the above specs.
Also, you don't want Pine64 to drain your battery when the alternator is off (car is off). This is where Ignition signal comes in. You would need to connect Ignition signal to a power transistor (MOSFET) that would control another power transistor on the Battery line.
I hope that makes sense.
So I've designed the following:
1. Power up circuit using Car's battery, ground and ignition signals. Pine64 will be powered on as long as the key is in the ignition and the engine is on.
2. 4 channel (FL, FR, RL and RR) analog audio amplifier (each channel delivers 50W).
3. Sound processor with 3 band equalizer (mid, bass, treble).
Currently I am working on a layout (not a layout guy - if someone has experience with KiCad, please let me know I could use some help). I will put all of these on one board (POT) that will plug in on top of Pine64.
I plan to have this completed in the next couple of weeks. I will keep you posted on the progress.
(03-04-2016, 02:46 AM)npull Wrote: a USB charger is a 12V to 5V converter, isn't it?
Using it's own battery was an alternative I was thinking of. Then you can monitor charging state instead, wake up when charging starts, go to sleep mode when charging stops. But how long would, lets say nexus 7's 4,325 mAh battery last in sleep mode for the pine64? What happens if you leave the car for a week and it dies, how can you then turn on the pine64 with the ignition?
From the car, you have Battery, Ground, and Ignition (Accessory) wires (signals).
Pine64 has DC_in on one of the connectors, which is I believe 5V. You would have to connect the two.
How:
Car's alternator will produce around 13.6V, so you will need a step down converter, to get to 5V. Ideal amperage for Pine64 (according to Pine64 folks) is 2A.
So, look for the converter with the above specs.
Also, you don't want Pine64 to drain your battery when the alternator is off (car is off). This is where Ignition signal comes in. You would need to connect Ignition signal to a power transistor (MOSFET) that would control another power transistor on the Battery line.
I hope that makes sense.
