mcf51mm256 Freescale Semiconductor, Inc, mcf51mm256 Datasheet - Page 21

• Manufacturer Part Number: mcf51mm256
• Description: 32-bit Coldfire V1 Central Processor Unit
• Manufacturer: Freescale Semiconductor, Inc

1
2
3
4
5
6
7
8
9
10
Freescale Semiconductor
Num
Typical values are measured at 25°C. Characterized, not tested
As the supply voltage rises, the LVD circuit will hold the MCU in reset until the supply has risen above V
Measured with V
All functional non-supply pins are internally clamped to V
Input must be current limited to the value specified. To determine the value of the required current-limiting resistor, calculate resistance values
for positive and negative clamp voltages, then use the larger of the two values.
Power supply must maintain regulation within operating V
injection current (V
regulation. Ensure external V
not consuming power. Examples are: if no system clock is present, or if clock rate is very low (which would reduce overall power consumption).
Maximum is highest voltage that POR is guaranteed.
Run at 1 MHz bus frequency
Low voltage detection and warning limits measured at 1 MHz bus frequency.
Factory trimmed at V
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22
23
24
Symbol
V
V
V
V
LVWH
LVWL
hys
BG
In
In
Low-voltage warning
threshold —
high range
Low-voltage warning
threshold —
low range
Low-voltage inhibit reset/recover hysteresis
Bandgap Voltage Reference
> V
DD
= V
DD
= 3.0 V, Temp = 25°C
DD
) is greater than I
.
DD
14
load will shunt current greater than maximum injection current. This will be the greatest risk when the MCU is
14
Characteristic
Table 9. DC Characteristics (continued)
DD
, the injection current may flow out of V
10
V
V
V
V
DD
DD
DD
DD
SS
DD
falling
rising
falling
rising
and V
range during instantaneous and operating maximum current conditions. If positive
DD
.
14
Condition
—
—
—
—
—
—
DD
and could result in external power supply going out of
1.145
Preliminary Electrical Characteristics
2.36
2.36
2.11
2.16
Min
—
LVDL
Typ
2.46
2.46
2.16
2.21
1.17
50
.
1
1.195
Max
2.56
2.56
2.22
2.27
—
Unit
mV
V
V
V
V
V
C
P
P
P
P
C
P
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