PHD User Guide
20
5. Power
The PHD family is powered by a direct battery connection. The display is turned on by applying power to
one of the wake-up inputs or a CAN message, depending on configuration in software. The direct battery
input is protected against vehicle transients such as load dump and inductive load switching, etc. It is
also protected against reverse battery voltage of -33 V through the use of a high-current path that will
cause an external fuse to blow.
The PHD operates in a 12 V or 24 V system and can operate from 9 V up to 32 V with over-voltage
protection at 33 V.
The following table provides specifications for the PHD power:
Parameter
Min
Nom
Max
Unit
Input voltage for normal operation
9
-
32
V
Minimum cranking voltage (see note 1)
7
-
V
Over-voltage protection
-
-
33
V
Reverse battery protection (see note 2)
-
-
-33
V
Recommended External Fuse
-
-
10
A
Maximum continuous current (see note 3)
VBATT=13.8 V
VBATT=27.0 V
0.44
0.22
1.781
0.93
A
A
Rating of External Fuse
-
-
3
A
Not 1e:
The unit will operate below 9 V, down to 7 V, but the LCD back-lighting may
be dim.
Not 2e:
A reverse battery condition causes an external fuse to blow.
Not 3e:
This is the maximum expected value, not including the additional draw of
the outputs, or the regulated 5VDC and 12VDC supplies.
