MB90F455 datasheet(13/80 Pages) FUJITSU

13 / 80 page

MB90455 Series

DS07-13728-5E

• Caution on Operations during PLL Clock Mode

• If the PLL clock mode is selected, the microcontroller attempt to be working with the self-oscillating circuit even

when there is no external oscillator or external clock input is stopped. Performance of this operation, however,

cannot be guaranteed.

• Sequence of turning on power of A/D converter and applying analog input

• Be sure to turn on digital power (Vcc) before applying signals to the A/D converter and applying analog input

signals (AN0 to AN7 pins).

• Be sure to turn off the power of A/D converter and analog input before turning off the digital power source.

• Be sure not to apply AVR exceeding AVcc when turning on and off. (No problems occur if analog and digital

power is turned on and off simultaneously.)

• Handling pins when A/D converter is not used

• If the A/D converter is not used, connect the pins under the following conditions: “AVcc=AVR=Vcc,” and

“Avss=Vss”

• Note on turning on power

• For preventing malfunctions on built-in step-down circuit, maintain a minimum of 50

μs of voltage rising time

(between 0.2 V and 2.7 V) when turning on the power.

• Stabilization of supply voltage

• A sudden change in the supply voltage may cause the device to malfunction even within the specified Vcc

supply voltage operating range. Therefore, the Vcc supply voltage should be stabilized.

For reference, the supply voltage should be controlled so that Vcc ripple variations (peak-to-peak values) at

commercial frequencies (50 Hz to 60 Hz) fall below 10

% of the standard VCC supply voltage and the coefficient

of fluctuation does not exceed 0.1 V/ms at instantaneous power switching.

MB90F455 Datasheet(PDF) 13 Page - fujitsu semiconductor