SC16C554DB NXP Semiconductors, SC16C554DB Datasheet - Page 19

• Manufacturer Part Number: SC16C554DB
• Description: 5 V 3.3 V and 2.5 V quad UART - 5 Mbit/s (max.) with 16-byte FIFOs
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 13133
Product data sheet
A single baud rate generator is provided for the transmitter and receiver, allowing
independent TX/RX channel control. The programmable Baud Rate Generator is capable
of accepting an input clock up to 80 MHz (for 3.3 V and 5 V operation), as required for
supporting a 5 Mbit/s data rate. The SC16C554B/554DB can be configured for internal or
external clock operation. For internal clock oscillator operation, an industry standard
microprocessor crystal (parallel resonant/22 pF to 33 pF load) is connected externally
between the XTAL1 and XTAL2 pins (see
be connected to the XTAL1 pin to clock the internal baud rate generator for standard or
custom rates (see
Programming the Baud Rate Generator registers DLM (MSB) and DLL (LSB) provides a
user capability for selecting the desired final baud rate.
Table 8:
Output baud rate
200
1200
2400
4800
9600
19.2 k
38.4 k
76.8 k
153.6 k
230.4 k
460.8 k
Fig 11. Crystal oscillator connection
Baud rate generator programming table using a 7.3728 MHz clock
Table
5 V, 3.3 V and 2.5 V quad UART, 5 Mbit/s (max.) with 16-byte FIFOs
Rev. 01 — 9 February 2005
User
16 clock divisor
Decimal
2304
384
192
96
48
24
12
6
3
2
1
XTAL1
8).
1.8432 MHz
C1
22 pF
X1
XTAL2
C2
33 pF
HEX
900
180
C0
60
30
18
0C
06
03
02
01
Figure
SC16C554B/554DB
11). Alternatively, an external clock can
XTAL1
1.8432 MHz
C1
22 pF
DLM
program value
(HEX)
09
01
00
00
00
00
00
00
00
00
00
X1
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
XTAL2
002aaa870
1.5 k
C2
47 pF
www.DataSheet4U.com
DLL
program value
(HEX)
00
80
C0
60
30
18
0C
06
03
02
01
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