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CHAPTER 2 HANDLING THE DEVICE
2.1
Notes on Handling Devices
This section describes latch-up prevention, pin processing, and circuit handling.
■
Latch-up prevention
CMOS ICs may suffer a latch-up when a higher voltage than V
CC
or a lower voltage than V
SS
is
applied to an input or output pin or when a voltage exceeding the applicable rating is applied
between V
CC
and V
SS
. This latch-up may rapidly increase power supply current, resulting in
thermal damage to an element. For this reason, ensure that the voltage to be applied does not
exceed the absolute maximum ratings.
■
Pin processing
❍
Unused pin processing
Leaving unused input pins open may result in a malfunction; pull them up or down.
❍
NC pin processing
Be sure to open the NC pin when using it.
❍
Output pin processing
Connecting one output pin with another, connecting an output pin with the power supply, or
connecting a large capacity load may cause flow of high current. Over a long period, this
condition results in device deterioration. For this reason, ensure that the current does not
exceed the absolute maximum ratings.
❍
Mode pins (MD0 to MD2)
Connect the MD0 to MD2 pins direct to V
CC
or V
SS
when using them. To prevent MB91150 from
entering the test mode mistakenly due to noise, make the pattern length between each mode
pin and V
CC
or V
SS
on a PC board as short as possible and connect these in low impedance.
❍
Power supply pins
If there are several V
CC
and V
SS
pins, those that must be set to the same potential in the device
are connected to each other in device design to prevent such malfunctions as latch-up. To
prevent the strobe signal from malfunctioning due to fluctuations in background radiation and
increase in ground level current or to observe the total output current regulations, be sure to
externally connect all these power supply pins to the power supply and ground.
Also, connect the power supply pins from the power supply source to the V
CC
and V
SS
pins of
this device at low impedance as far as possible. In addition, a ceramic capacitor of about 0.1
µ
F
should be connected between V
CC
and V
SS
pins near this device as a bypass capacitor.
Summary of Contents for MB91150 Series
Page 1: ......
Page 2: ......
Page 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
Page 4: ......
Page 10: ...vi ...
Page 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Page 178: ...162 CHAPTER 5 I O PORTS ...
Page 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Page 240: ...224 CHAPTER 8 PPG TIMER ...
Page 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Page 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Page 362: ...346 CHAPTER 15 UART ...
Page 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Page 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Page 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 510: ...494 INDEX ...
Page 512: ......