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Philips Semiconductors
Product specification
SC28L198
Octal UART for 3.3V and 5V supply voltage
1999 Jan 14
44
AC ELECTRICAL CHARACTERISTICS FOR COMMERCIAL AND INDUSTRIAL (5V) (Continued)
VCC = 5.0 volts " 10%; TA = –40 to 85°C; unless otherwise specified
SYMBOL
FIG#
PARAMETER
LIMITS
UNIT
MIN
TYP
MAX
Sclk Timing
tsclkl
Min low time at VIL (0.8V)
11
5
ns
tsclkh
Min high time at VIH (2.0V)
11
5
ns
Fsclk
Sclk frequency
0.1
33
MHz
t/RFsck
Sclk rise and fall time (0.8 to 2.0Volts)
3
ns
X1/X2 Communication Crystal Clock
Fx15
X1 clock frequency
1
3.6864
8.0
MHz
X1 L / H
X1 Low / High time
32
135
ns
T/RFx1
X1 Rise and Fall time
10
ns
Counter/Timer Baud Rate Clock (External Clock Input)
FC/T4
Clock frequency
0
8
MHz
TC/TLH
C/T high and low time
15
11
ns
TC/TO
Delay C/T clock external to output pin
48
60
ns
DTACK Timing
DAKdly
DACK low from Sclk C4 rising edge
10
18
ns
DAKdlya
DACK high from CEN high (Async)
11
20
ns
DAKdlys
DACK high from C4 end rising edge (Sync)
11
20
ns
I/O Port External Clock
tgpirtx
GPI to Rx/Tx clock out
32
50
ns
RxD setup to I/OP rising edge 1X mode
20
2
ns
I/OP falling edge to TxD out 1X mode
32
60
ns
Gout Timing
GPOtdd
GPO valid after write to GPOR
100
ns
NOTES:
1. Timing is illustrated and referenced with respect to W–RN and CEN inputs. Internal read and write activities are controlled by the Sclk as it
generates the several “C” timing as shown in the timing diagrams.
2. The minimum time before the rising edge of the next C2 time to stop the next bus cycle. CEN must return high after midpoint of C4 time and
before the C2 time of the next cycle.
3. Delay is from CEN high in Async mode to IRQN inactive, from end of C4 to IRQN inactive in Sync mode.
4. The minimum frequency values are not tested, but are guaranteed by design.
5. 1MHz specification is for crystal operation.