User's Manual

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M2x40 Mote Datasheet Dust Networks™ 9
7.0 Mote Boot Up
7.1 Power-on Sequence
The M2x40 mote has internal power-on-reset circuits that ensure that the mote will properly boot. However, for the power-
on-reset circuitry to function properly, the external power supply must meet the timing shown in Figure 1 and specified in
Table 10.
Figure 1 External Power Supply Timing Requirement
The following reset sequence (shown in Figure 2 and specified in Table 10) is required for external power supplies that fail to
meet the requirement above.
Figure 2 Power-on Sequence
Table 10 Power-on Sequence
Parameter Min Typ Max Units Comments
T
Vcc2RST
0 ms
T
VccRv1v2
10 µs
7.2 Inrush Current
During power on, the mote can be modeled as a lumped impedance, as shown in Figure 3 . With a source impedance (R
src
) of
1 Ω, the inrush current on the mote appears as shown in Figure 4.
Figure 3 M2x40 Equivalent Series RC Circuit