DUART
7 DUART
This section describes the DC and AC electrical specifications for the DUART interface of the
MPC8548E.
7.1
DUART DC Electrical Characteristics
Table 20 provides the DC electrical characteristics for the DUART interface.
Table 20. DUART DC Electrical Characteristics
Parameter
Symbol
Min
Max
Unit
High-level input voltage
V
2
–0.3
—
OV + 0.3
V
V
IH
DD
Low-level input voltage
V
I
0.8
±5
—
IL
1
Input current (V
= 0 V or V = V
μA
V
IN
IN
DD)
IN
High-level output voltage (OV = min, I = –2 mA)
V
OH
2.4
—
DD
OH
Low-level output voltage (OV = min, I = 2 mA)
V
OL
0.4
V
DD
OL
Note:
1. Note that the symbol V , in this case, represents the OV symbol referenced in Table 1 and Table 2.
IN
IN
7.2
DUART AC Electrical Specifications
Table 21 provides the AC timing parameters for the DUART interface.
Table 21. DUART AC Timing Specifications
Parameter
Value
Unit
Notes
Minimum baud rate
Maximum baud rate
Oversample rate
f
/1,048,576
baud
baud
—
1, 2
1, 2, 3
1, 4
CCB
f
/16
CCB
16
Notes:
1. Guaranteed by design.
2. f
refers to the internal platform clock.
CCB
3. Actual attainable baud rate will be limited by the latency of interrupt processing.
th
4. The middle of a start bit is detected as the 8 sampled 0 after the 1-to-0 transition of the start bit. Subsequent bit values are
th
sampled each 16 sample.
MPC8548E PowerQUICC™ III Integrated Processor Hardware Specifications, Rev. 6
Freescale Semiconductor
25
FREESCALE [ Freescale ]
