Hardware manual

31
FUJITSU SEMICONDUCTOR CONFIDENTIAL
MB96630 Series
DS704-00012-1v0-E
9. Notes on Power-on
To prevent malfunction of the internal voltage regulator, supply voltage profile while turning the power supply
on should be slower than 50µs from 0.2V to 2.7V.
10. Stabilization of power supply voltage
If the power supply voltage varies acutely even within the operation safety range of the V
CC
power supply
voltage, a malfunction may occur. The V
CC
power supply voltage must therefore be stabilized. As stabilization
guidelines, the power supply voltage must be stabilized in such a way that V
CC
ripple fluctuations (peak to peak
value) in the commercial frequencies (50Hz to 60Hz) fall within 10% of the standard V
CC
power supply voltage
and the transient fluctuation rate becomes 0.1V/µs or less in instantaneous fluctuation for power supply
switching.
11. Serial communication
There is a possibility to receive wrong data due to noise or other causes on the serial communication.
Therefore, design a printed circuit board so as to avoid noise.
Consider receiving of wrong data when designing the system. For example apply a checksum and retransmit
the data if an error occurs.
12. Mode Pin (MD)
Connect the mode pin directly to Vcc or Vss pin. To prevent the device unintentionally entering test mode due to
noise, lay out the printed circuit board so as to minimize the distance from the mode pin to Vcc or Vss pin and
provide a low-impedance connection.