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Page 9
Shoot First, Ask Questions Later
When the MicroPAC is operating in categories 1 to 3 and detects an increase in load
current applied to the output which incurs into the next power band the internal
microcontroller will turn all outputs on, regardless of the actual amount of load added.
(Shoot first ask question later) with all the outputs enabled, the microcontroller will
turn off redundant outputs
In the Power Shed Mode this is a constant cycle of detecting output load and continually
adjusting the outputs to satisfy that need.
No Load Power Dissipation with and without Power Shed Mode
1
2
3
4
5
7.5
10
12.5
15
17.5
20
22.5
25
27.5
30
7.06
7.055
7.05
7.045
7.04
Power Shed Mode Disabled
Power Shed Mode Enabled
Number of BCM’s
Power (Was)
Power (Was)
1
2
3
4
5
8
11
14
17
20
23
26
29
32
35
8.26
8.255
8.25
8.245
8.24
Power Shed Mode Disabled
Power Shed Mode Enabled
Number of BCM’s
Power (Was)
Powe
r (Was)
Figure 5.
No Load Power Dissipation @
25°C with 12 V Output
With the power shed enabled
the average power dissipation
is about 7.05 W
With the power shed disabled
the power dissipation
is around 28.20 W
Figure 6.
No Load Power Dissipation @
25°C with 48 V Output
With the power shed enabled
the average power dissipation
is about 8.25 W;
With the power shed disabled
the power dissipation
is around 33 W.
