MB90560/565 Series
X0
X1
OPEN
MB90560/565 series
Example of using an external clock
(7) Power supply pins
The multiple VCC and VSS pins are connected together in the internal device design so as to prevent misoperation
such as latch-up. However, always connect all VCC and VSS pins to the same potential externally to minimize
spurious radiation, prevent misoperation of strobe signals due to increases in the ground level, and maintain the
overall output current rating.
Also, ensure that the impedance of the VCC and VSS connections to the power supply is as low as possible.
To minimize these problems, connect a bypass capacitor of approximately 0.1 µF between VCC and VSS. Connect
the capacitor close to the VCC and VSS pins.
(8) Sequence for connecting and disconnecting power supply
Do not apply voltage to the A/D converter power supply pins (AVCC, AVR, AVSS) or analog inputs (AN0 to AN7)
until the digital power supply (VCC) is turned on. When turning the device off, turn off the digital power supply
after disconnecting the A/D converter power supply and analog inputs. When turning the power on or off, ensure
that AVR does not exceed AVCC.
When using the I/O ports that share pins with the analog inputs, ensure that the input voltage does not exceed
AVCC (turning the analog and digital power supplies on and off simultaneously is OK) .
(9) Conditions when output from ports 0 and 1 is undefined
After turning on the power supply, the outputs from ports 0 and 1 are undefined during the oscillation stabilization
delay time controlled by the regulator circuit (during the power-on reset) if the RST pin level is “H”. When the
RST pin level is “L”, ports 0 and 1 go to high impedance.
Figures 1 and 2 show the timing (for the MB90F562/B and MB90V560) .
Note that this undefined output period does not occur on products without an internal regulator circuit as these
products do not have an oscillation stabilization delay time.
(MB90561/A, MB90562/A, MB90F568, and MB90567/8)
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