mc68hc11e0fnr2 Freescale Semiconductor, Inc, mc68hc11e0fnr2 Datasheet - Page 21

• Manufacturer Part Number: mc68hc11e0fnr2
• Description: Hc11 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

1.4.1 V
Power is supplied to the MCU through V
operates from a single 5-volt (nominal) power supply. Low-voltage devices in the E series operate at
3.0–5.5 volts.
Very fast signal transitions occur on the MCU pins. The short rise and fall times place high, short duration
current demands on the power supply. To prevent noise problems, provide good power supply bypassing
at the MCU. Also, use bypass capacitors that have good
high-frequency characteristics and situate them as close to the MCU as possible. Bypass requirements
vary, depending on how heavily the MCU pins are loaded.
Freescale Semiconductor
DD
and V
OPTIONAL POWER-ON DELAY AND MANUAL RESET SWITCH
RESET SWITCH
MANUAL
SS
4.7 kΩ
Figure 1-8. External Reset Circuit with Delay
V DD
Figure 1-7. External Reset Circuit
M68HC11E Family Data Sheet, Rev. 5.1
4.7 k Ω
1.0 µF
MC34(0/1)64
GND
V DD
IN
DD
2
3
RESET
and V
MC34164
GND
IN
1
RESET
SS
V DD
. V
4.7 kΩ
DD
is the power supply, V
MC34064
TO RESET
OF M68HC11
GND
V DD
IN
RESET
V DD
4.7 kΩ
SS
is ground. The MCU
TO RESET
OF M68HC11
Pin Descriptions
21