UNICORECOMM UM982 - Grounding and Heat Dissipation; Power-On and Power-Off

UM982 User Manual
14 Hardware Design UC-00-M31 EN P1.0.0
3.2 Grounding and Heat Dissipation
Figure 3-2 Grounding and Heat Dissipation Pad
The 35 pads in the rectangle in Figure 3-2 are for grounding and heat dissipation. In the
PCB design, it is recommended to connect them to a large sized ground to strengthen
the heat dissipation.
3.3 Power-on and Power-off
The VCC initial level when power-on should be less than 0.4 V and has good
monotonicity. The voltages of undershoot and ringing should be within 5% VCC.
VCC power-on waveform: The time interval from 10% rising to 90% must be within
100 us ~1 ms.
Power-on time interval: The time interval between the VCC < 0.4 V (after power-off) to
the next power-on must be larger than 500 ms.
Grounding and
heat dissipation pad