AN1836 Motorola / Freescale Semiconductor, AN1836 Datasheet - Page 21

• Manufacturer Part Number: AN1836
• Description: FLASH Programming for Motorola MC68HC912 Microcontrollers
• Manufacturer: Motorola / Freescale Semiconductor

Programming Voltage Supply Considerations
Programming
Voltage Supply
Envelope
AN1836
MOTOROLA
NOTE:
The key to preventing damage to the FLASH array or corruption of the
data contained in the memory is the programming voltage envelope
shown in
with FLASH devices are due to a failure to ensure that their voltage
sources always meet these requirements.
The most important single thing to remember from this diagram is that
V
actual program or erase cycle. Corruption of FLASH data is often
encountered when V
and power-down phases.
Conversely, if V
time, damage to the FLASH array can occur.
Although
the normal read phase, V
below V
5.2 volts, V
FP
and V
–0.30 V
13.5 V
12.6 V
11.4 V
4.15 V
5.5 V
4.5 V
DD
0 V
Figure
Figure 9
DD
. For example, If the operating voltage of V
FP
POWER
Figure 9. Programming Voltage Envelope
should always be at the same level, except during an
can be no lower than 4.85 volts.
UP
FP
9. Many of the problems that customers experience
is allowed to fall below .35 volts lower than V
shows a lower boundary of 4.15 volts on V
FP
NORMAL
is allowed to exceed V
READ
FP
always must be no more than .35 volts
PROGRAM
Programming Voltage Supply Considerations
ERASE
30 ns MAXIMUM
DD
POWER
DOWN
t
ER
during the power-up
V
V
COMBINED V
FP
DD
DD
ENVELOPE
ENVELOPE
in the system is
Application Note
DD
FP
DD
AND V
during
at any
FP
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