Notes On Handling Devices - Fujitsu F2MC-8L Series Hardware Manual

CHAPTER 2 HANDLING DEVICES
2.1

Notes on Handling Devices

This section lists points to note regarding the power supply voltage, pins, and other
device handling aspects.
Notes on Handling Devices
Take great care not to exceed the maximum rated voltage (preventing latchup).
Latchup may occur on CMOS ICs if voltage higher than V
input and output pins other than medium- and high-voltage pins, or if voltage higher than the
ratings is applied between V
When latchup occurs, power supply current increases rapidly and might thermally damage
elements. When using, take great care not to exceed the absolute maximum ratings.
Also, take care to prevent the analog power supply (AV
exceeding the digital power supply (V
and off.
Stabilizing supply voltage is important.
A rapid fluctuation of V
within the operation assurance range of the voltage. As stabilization guidelines, it is
recommended to control power so that V
of the standard V
fluctuation rate will be less than 0.1 V/ms at the time of a momentary fluctuation such as when
power is switched.
Treatment of unused input pins
Leaving unused input pins open could cause malfunctions. They should be connected to a pull-
up or pull-down resistor.
Treatment of N.C. pins
Be sure to leave N.C. (internally connected) pins open.
Treatment of power supply pins on microcontroller with A/D or D/A converters
Connect to be AV
are not in use.
Precautions when using an external clock
Even when an external clock is used, oscillation stabilization delay time is required for power-on
reset (optional) and wake-up from subclock mode and stop mode.
Increasing the power supply voltage (for MB89P135A only)
When MB89P135A is used, the power supply voltage must be increased to 2.0V within 13
clocks after oscillation.
If the power supply is started without satisfying this requirement, the option settings may not
22
and V .
CC SS
CC
power supply voltage could cause malfunctions, even if it occurs
CC
value at the commercial frequency (50 to 60 Hz) and the transient
CC
= DAVC = V and AV
CC CC
CC
and AVR) and analog input from
CC
) when the analog system power supply is turned on
ripple fluctuations (P-P value) will be less than 10%
CC
= AVR = V even if the A/D and D/A converters
SS SS
or lower than V is applied to
SS