TWR-56F8257 Freescale Semiconductor, TWR-56F8257 Datasheet - Page 56

• Manufacturer Part Number: TWR-56F8257
• Description: TOWER SYSTEM KIT MC56F8257
• Manufacturer: Freescale Semiconductor
• Type: DSC, Digital Signal Controllerr

Specifications of TWR-56F8257

• Contents: Board, Cables, Documentation, DVD
• For Use With/related Products: Freescale Tower System, MC56F8257
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Specifications
7.8
7.9
The MC56F825x/MC56F824x has two on-chip regulators. One supplies the PLL, crystal oscillator, NanoEdge placement
PWM, and relaxation oscillator. It has no external pins and therefore has no external characteristics that must be guaranteed
(other than proper operation of the device). The second regulator supplies approximately 2.5 V to the
MC56F825x/MC56F824x’s core logic. For proper operation, this regulator requires an external capacitor of 2.2 µF or greater.
Ceramic and tantalum capacitors tend to provide better performance tolerances. The output voltage can be measured directly
on the V
7.10
Tests are conducted using the input levels specified in
from the 50% to the 50% point, and rise and fall times are measured between the 10% and 90% points, as shown in
56
CAP
Input Signal
1
2
3
4
Power-On Reset, Low Voltage Detection Specification
Voltage Regulator Specifications
AC Electrical Characteristics
Low-Voltage Interrupt for 3.3 V supply
Low-Voltage Interrupt for 2.5 V supply
Low-Voltage Interrupt Recovery Hysteresis
Power-On Reset Threshold
Brown-Out Reset Threshold
(V
pin. The specifications for this regulator appear in
Brown-Out Reset occurs whenever the internally regulated 2.5 V digital supply drops below 1.8 V.
When V
When V
While power is ramping up, this signal remains active for as long as the internal 2.5 V is below 2.18 V or
the 3.3 V V
voltage is typically 100 mV less than V
ulates.
Short Circuit Tolerance
Short Circuit Current
CAP
Characteristic
shorted to ground)
DD
DD
drops below LVI27, an interrupt is generated.
drops below LVI21, an interrupt is generated.
DD
Table 25. Power-On Reset and Low-Voltage Detection Parameters
Characteristic
voltage is below 2.7 V, no matter how long the ramp-up rate is. The internally regulated
Fall Time
Midpoint1
MC56F825x/MC56F824x Digital Signal Controller, Rev. 3
Figure 15. Input Signal Measurement References
V
3
IH
4
Table 26. Regulator Parameters
The midpoint is V
DD
1
2
Symbol
T
during ramp-up until 2.5 V is reached, at which time it self-reg-
I
RSC
SS
Table
Low
V
IL
Symbol
23. Unless otherwise specified, propagation delays are measured
V
V
POR
BOR
V
LVI27
LVI21
IL
EIH
Table
+ (V
Min
—
—
IH
26.
– V
Min
IL
2.6
2.6
—
—
—
)/2.
Typical
Rise Time
900
—
High
2.18
Typ
2.7
2.7
1.8
50
1300
Max
30
Max
2.8
2.8
1.9
—
—
Freescale Semiconductor
90%
50%
10%
Unit
mV
V
V
V
V
minutes
Unit
mA
Figure
15.