mb91307r Fujitsu Microelectronics, Inc., mb91307r Datasheet - Page 14

• Manufacturer Part Number: mb91307r
• Description: 32-bit Microcontroller Cmos Fr60 Mb91307 Series
• Manufacturer: Fujitsu Microelectronics, Inc.

14
MB91307 Series
• Preventing Latchup
• Treatment of unused pins
• About power supply pins
• Notes on Power-ON/shut-down
• Precautions for use of stop mode
MB91307 Series
HANDLING DEVICES
When CMOS integrated circuit devices are subjected to applied voltages higher than V
pins (other than medium- and high-withstand voltage pins), or to voltages lower than V
in excess of rated levels are applied between V
a latchup condition occurs, supply current can increase dramatically and may destroy semiconductor elements.
In using semiconductor devices, always take sufficient care to avoid exceeding maximum ratings.
Do not leave an unused input pin open, since it may cause a malfunction. Handle by, using a pull-up or
pull-down resistor.
In products with multiple V
to avoid abnormal operations including latch-up. However, you must connect the pins to external power supply
and a ground line to lower the electro-magnetic emission level, to prevent abnormal operation of strobe signals
caused by the rise in the ground level, and to conform to the total output current rating.
Moreover, connect the current supply source with the V
It is also advisable to connect a ceramic bypass capacitor of approximately 0.1 mF between V
this device.
Cautions to take when turning on/off V
supply)
Do not apply V
nected not to cause a reliability problem with the LSI.
When V
example, due to power supply noise.
The built-in regulator in this device stops operating when the device is in stop mode. In such cases as when
increased leak current (I
operating mode cause the regulator to stop, the internal 2.5 V power supply can ball below the voltage at which
operation is assured. Therefore it is necessary when using the internal regulator and stop mode to assure that
the external power supply does not fall below 3.3 V. And even if this should occur, the internal regulator can be
set to restart when a reset is applied. (In this case the oscillator stabilization wait period should also be set to
“L” level.)
When the power is turned on
When the power is turned off
SS
(external) returns from the OFF state to the ON state, the circuit may fail to hold its internal state, for
SS
(external) alone continuously (for over an indication of one minute) with V
CCH
CC
) in stop mode, or abnormal operation or power fluctuation due to noise while in
or V
SS
pins, the pins of the same potential are internally connected in the device
V
Signal → V
CCI
CCI
(1.8-V internal power supply) and V
(internal) → V
CC
SS
and V
(external) → V
CC
SS
SS
, a phenomenon known as latchup can occur. When
and V
(external) → Signal
SS
pins of this device at the low impedance.
CCI
(internal)
SS
(3.3-V external-pin power
SS
, as well as when voltages
CC
CCI
at input and output
(internal) discon-
CC
and V
SS
near