Terminal block
Strato Pi CM has a 5 positions terminal block for power and serial connections.
The maximum conductor cross section is 1.5 mm
2
(16 AWG), or 0.5 mm
2
when using
ferrules (highly recommended). Recommended stripping length is 5 mm. Screw thread is
M2. Never exceed 0.25 Nm torque when tightening the screws.
Power supply
Strato Pi CM can be powered with DC voltage only:
✓
DC: nominal voltage range 9V to 28.0V.
Respect the correct polarity shown in the schematic diagram (+ -). The power supply
circuit implements reverse polarity protection using an auto resetting fuse and surge
protection up to ±1000V/2ohms 1.2/50
μ
s.
A blue on-board LED, also visible through the front panel of the DIN rail case, is lit when
power supply is available. This LED also blinks while the Compute Module boot process is
in progress.
The Strato Pi CM power supply stage is optimised to deliver up to 1.9A at 5V to the
Raspberry Pi Compute Module.
The voltage regulator can supply up to 3.0A 5V output short duration current peaks
(<1sec).
Because Strato Pi CM has a 1.1A resettable fuse (polyfuse) on the power supply line, the
maximum current that its regulator can deliver is also limited by this fuse, and depends on
the input voltage.
The following table lists the typical measured output current of the power supply stage at
different input voltages, and the corresponding input current. At high input voltage levels,
the voltage regulator’s thermal protection becomes the limiting factor.
STRATO PI CM POWER SUPPLY STAGE TYPICAL IN/OUT VOLTAGE AND CURRENT
FUSE marks the level where the polyfuse opens to limit input current; REG is the voltage
regulator's thermal protection limit.
14
Strato Pi CM User Guide
