DS07-16301-4E Datasheet, PDF (16/99 Pages) Fujitsu Component Limited. – 32-bit RISC Microcontroller CMOS FR30 Series

MB91101/MB91101A
The MB91101 and MB91101A have an internal regulator. When using with 5 V power supply, supply 5 V to VCC5
pin and make sure to connect about 0.1 µF bypass capacitor to VCC3 pin for regulator. And another 3 V power
supply is needed for the A/D convertor. When using with 3 V power supply, connect both VCC5 pin and VCC3 pin
to the 3 V power supply.
• Connecting to a power supply
5V
3V
GND
[Using with 5 V power supply]
3V
VCC5
VCC3
AVCC
AVRH
AVSS
VSS
About
0.1 µF
GND
[Using with 3 V power supply]
VCC5
AVCC
AVRH
AVSS
VSS
VCC3
6. Crystal Oscillator Circuit
Noises around X0 and X1 pins may cause malfunctions of the MB91101 and MB91101A. In designing the PC
board, layout X0 and X1 pins, crystal oscillator (or ceramic oscillator) and bypass capacitor for grounding as
close as possible.
It is strongly recommended to design PC board so that X1 and X0 pins are surrounded by grounding area for
stable operation.
7. Turning-on Sequence of A/D Converter Power Supply and Analog Input
Make sure to turn on the digital power supply (VCC) before turning on the A/D converter (AVCC, AVRH) and applying
voltage to analog input (AN0 to AN3).
Make sure to turn off digital power supply after power supply to A/D converters and analog inputs have been
switched off. (There are no such limitations in turning on power supplies. Analog and digital power supplies may
be turned on simultaneously.) Make sure that AVRH never exceeds AVCC when turning on/off power supplies.
8. Fluctuation of Power Supply Voltage
Warranty range for normal operation against fluctuation of power supply voltage VCC is as given in rating. However,
sudden fluctuation of power supply voltage within the warranty range may cause malfunctions. It is recommended
to make every effort to stabilize the power supply voltage to IC. It is also recommended that by controlling power
supply as a reference of stabilizing, VCC ripple fluctuation (P-P value) at the commercial frequency (50 Hz to
60 Hz) should be less than 10% of the standard VCC value and the transient regulation should be less than
0.1 V/ms at instantaneous deviation like turning off the power supply.
9. Mode Setting Pins (MD0 to MD2)
Connect mode setting pins (MD0 to MD2) directly to VCC or VSS.
Arrange each mode setting pin and VCC or VSS patterns on the printed circuit board as close as possible and
make the impedance between them minimal to prevent mistaken entrance to the test mode caused by noises.
10. Internal DC Regulator
Internal DC regulator stops in stop mode. When the regulator stops owing to the increase of inner leakage
current (ICCH) in stop mode, malfunction caused by noise or any troubles about power supply in normal operation,
the internal 3 V power supply voltage may decrease less than the warranty range for normal operation. So when
using the internal regulator and stop mode with 5 V power supply, never fail to support externally so that 3 V
power supply voltage might not decrease. However, even in such a case, the internal regulator can be restarted
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