SC28L194 Philips Semiconductors, SC28L194 Datasheet - Page 45

• Manufacturer Part Number: SC28L194
• Description: Quad UART for 3.3V and 5V supply voltage
• Manufacturer: Philips Semiconductors

Philips Semiconductors
1998 Sep 21
NOTES:
C1 and C2 should be based on manufacturer’s specification.
X1 and X2 parasitic capacitance IS 1-2pF AND 3-5pF, respectively.
GAIN:
PHASE: at 4MHz 272 to 276 ; at 8MHz 272 to 276
The above figures for 5V operation. Operation at 3V is to be determined.
Quad UART for 3.3V and 5V supply voltage
NOTE: CEN must not be active during an IACKN cycle. If CEN is active, IACKN will be ignored
C1 and C2 should be chosen according to the
crystal manufacturer’s specification.
C1 and C2 values will include any parasitic
capacitance of the wiring.
ADDRESS
DACKN
IACKN
W_RN
SCLK
DATA
CEN
at 4MHz 8 to 14db; at 8MHz 2 to 6db
and a normal read or write will be executed according to W_RN. In the synchronous
mode, extended IACKN signal will start another IACKN. (This may not be desired, but
is allowed.)
T/R f
INVALID
X1
C1 = C2 = 24pF FOR C
C1
C2
t
CS
3.6864MHz
C1
L
INVALID
Figure 9. X1/X2 Communication Crystal Clock
= 20pF
Figure 8. Basic IACKN Cycle, ASYNC/SYNC
f
X1
t
RWS
X1 L/H
X1
X2
C2
DON’T CARE
DON’T CARE
28C194
45
FREQUENCY:
LOAD CAPACITANCE (C
TYPE OF OPERATION:
4pF
3pF
t
AS
50 KOHMs
TO
150 KOHMs
C3
t
AH
t
DD
L
TYPICAL CRYSTAL SPECIFICATION
):
TO I/O CHANGE-OF-STATE DETECTORS
DAK
2 – 4MHZ
12 – 32pF
PARALLEL RESONANT, FUNDAMENTAL MODE
C4
C4
DLY
VALID
+5V
2
1K required for
38.4kHz CLOCK
NC
BRG
TTL gate.
DAK
CEN
HIGH
INVALID
DLY
t
DF
Preliminary specification
MUX
SC28L194
22
INVALID
SD00525
STANDARD
BAUD
RATES
X1
X2
To
remainder
of circuit
SD00670