MB89470 データシートの表示（PDF） - Fujitsu

部品番号

コンポーネント説明

メーカー

MB89470

8-bit Proprietary Microcontroller

Fujitsu 

MB89470 Series

s HANDLING DEVICES

1. Preventing Latchup

Latchup may occur on CMOS ICs if voltage higher than VCC or lower than VSS is applied to input and output pins

other than medium- to high-voltage pins or if higher than the voltage which shows on “1. Absolute Maximum

Ratings” in “s ELECTRICAL CHARACTERISTICS” is applied between VCC and VSS.

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 (AVCC) and analog input from exceeding the digital power

supply (VCC) when the analog system power supply is turned on and off.

2. 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.

3. Treatment of Power Supply Pins on Microcontrollers with A/D Converter

Connect to be AVCC = VCC and AVSS = VSS even if the A/D converter is not in use.

4. Treatment of N.C. Pins

Be sure to leave (internally connected) N.C. pins open.

5. Power Supply Voltage Fluctuations

Although VCC power supply voltage is assured to operate within the rated range, a rapid fluctuation of the voltage

could cause malfunctions, even if it occurs within the rated range. Stabilizing voltage supplied to the IC is therefore

important. As stabilization guidelines, it is recommended to control power so that VCC ripple fluctuations (P-P

value) will be less than 10% of the standard VCC value at the commercial frequency (50 Hz to 60 Hz) and the

transient fluctuation rate will be less than 0.1 V/ms at the time of a momentary fluctuation such as when power

is switched.

6. Precautions when Using an External Clock

Even when an external clock is used, oscillation stabilization time is required for power-on reset (optional) and

wake-up from stop mode.

7. Note to noise in the External Reset Pin (RST)

If the reset pulse applied to the external reset pin (RST) does not meet the specifications, it may cause malfunc-

tions. Use causion so that the reset pulse less than the specifications will not be fed to the external reset pin (RST).

13

Share Link: