mb91101 Fujitsu Microelectronics, Inc., mb91101 Datasheet - Page 16

• Manufacturer Part Number: mb91101
• Description: 32-bit Risc Microcontroller Cmos
• Manufacturer: Fujitsu Microelectronics, Inc.

16
MB91101/MB91101A
6. Crystal Oscillator Circuit
7. Turning-on Sequence of A/D Converter Power Supply and Analog Input
8. Fluctuation of Power Supply Voltage
9. Mode Setting Pins (MD0 to MD2)
10. Internal DC Regulator
The MB91101 and MB91101A have an internal regulator. When using with 5 V power supply, supply 5 V to V
pin and make sure to connect about 0.1 F bypass capacitor to V
supply is needed for the A/D convertor. When using with 3 V power supply, connect both V
to the 3 V power supply.
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.
Make sure to turn on the digital power supply (V
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 AV
Warranty range for normal operation against fluctuation of power supply voltage V
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, V
60 Hz) should be less than 10% of the standard V
0.1 V/ms at instantaneous deviation like turning off the power supply.
Connect mode setting pins (MD0 to MD2) directly to V
Arrange each mode setting pin and V
make the impedance between them minimal to prevent mistaken entrance to the test mode caused by noises.
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
• Connecting to a power supply
GND
5 V
3 V
[Using with 5 V power supply]
V
AV
AVRH
AV
V
CC
SS
CC
SS
5
CC
CC
V
ripple fluctuation (P-P value) at the commercial frequency (50 Hz to
CC
or V
3
SS
CC
) before turning on the A/D converter (AV
patterns on the printed circuit board as close as possible and
CC
value and the transient regulation should be less than
About
0.1 F
CC
or V
GND
3 V
SS
.
CC
3 pin for regulator. And another 3 V power
CC
when turning on/off power supplies.
V
AV
AVRH
AV
V
[Using with 3 V power supply]
CC
SS
CC
CC
SS
5
is as given in rating. However,
CC
V
, AVRH) and applying
CC
CC
3
5 pin and V
CC
3 pin
CC
5