ORBCOMM OG2 Modem Integration Manual
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Figure 4-2 Input Voltage Rise Times
4.3
Dip, Interruptions, Surges, Fast transients
4.3.1
Dip & Interruptions
The power circuit has a soft start feature which allows a 750us rise or fall time for events which
occur faster than this time frame. The time that would cause deregulation is dependent upon the
input voltage and load at the time of the event.
Based on simulation, the processor (shown in gray) will operate for 1.3 ms after removal of an input
voltage of 4.0v, and will operate for 220ms when operating with an input voltage of 10 volts.
If the processor experiences an interruption, the processor low voltage detection will operate. The
circuit warning mode will create a system interrupt service routine and protect memory contents.
In the reset level detect mode a lower voltage threshold causes a power-on reset. The processor
will be held in reset until the rise-voltage threshold is achieved, then clock circuits will begin to
operate, when the voltage rises above the low-voltage threshold the system begins to operate. If
the processor is writing a new message in to memory during a power interruption, a protocol will
not provide an acknowledgement so the user processor will retry. The malformed message will be
Processor
Receiver
Power Amplifier
Input Power
