Power supply

[VojislavM]

Power supply diagram:

5V and 9V power supply are separated besause on the 9V there is inductive load.

[VojislavM]

Based on #2 DC DC 5V and 9V are isolated power modules.
Characteristics:

• Vin(5V and 9V) = ~12V to ~36V
• Vout(5V) = 5V, Imax(5V) = ~3A to 4A
• Vout(9V) = 9V, Imax(9V) = ~1A

[VojislavM]

For the 5V DC-DC:

• Imax = 0.4A + 2*1A + max(0.4A, 0.7A) = 3.1A

Because Raspberry Pi compute module won't use some parts of the system like GPU, 3D graphics, HDMI, etc. the overall consumption will be smaller, so we can use the 3A@5V output on the isolated DC-DC power supply.

After testing, gettering the data about consumption and analyzing it, we can probably decrease the power of the DC-DC output.

Current optimal solution for 5V, without knowing the consumption data, is MURATA POWER SOLUTIONS SPM15-050-Q12P-C Isolated Board Mount DC/DC Converter

[VojislavM]

FOR the 9V DC-DC:

The motor is normally rated at 5V and ~60 ohms, so each winding will take ~80mA with one
winding active, ~160mA with two (some step patterns like full-wave do this). Because the 24byj48-03 stepper motor is not reliable at 5V it is better to use 9V or 12V
At 9V supply, those values will be 150mA and 300mA, and at 12V supply, those values will be 200mA and 400mA instead.

At worst scenario we will have two motors running, so:

• Imax(9V) = 2 * 300mA + 7.4mA(for the MCU) = 607.4 mA
• Imax(12V) = 2 * 400mA + 7.4mA(for the MCU) = 807.4 mA

Because lowering the power is always the priority, 9V power output from the DC-DC module is more than enough. Also, Imax should not be below 650mA.

After testing, gathering the data about consumption and analyzing it, we can probably decrease the power of the DC-DC output.

Current optimal solution for 9V, without knowing the consumption data, is XP POWER ITX2409SA Isolated Board Mount DC/DC Converter

[VojislavM]

For SFP 3V3:

One SFP module uses aproximatly ~ 200mA so:

• Imax = 2 * 200mA = 400mA

Because there is low voltage drop, from 5V to 3.3V we will use Low Dropout Positive Regulator REG1117

[VojislavM]

For CM 3V3 and 1V8:

Currently the PAM2306 is in use. It is recommended form Raspberry pi foundation and it is on there CM base board.

Other option for 3V3 and 1V8 is Low Dropout Positive Regulator REG1117 with 1A output. Is is less efficient because it is linear but it is easier to solder by hand, but PAM2306AYPKE is several time cheaper.

[VojislavM]

In the new version there is no need for 9V power regulator. There will be only 5V and that vlotage will be step up on the move driver.

[VojislavM]

5V DCDC module will stay same, because it has more then enough power for the hole system. Onother option will be separate koruza-power-module with the same footprint

[VojislavM]

another option for power is non isolated DCDC the one form #2

[VojislavM]

There will be two option, both with 5V output:

1. Isolated: DCDC converter
2. Non-Isolated: koruza-power-module