xr16l2552im Exar Corporation, xr16l2552im Datasheet - Page 10

• Manufacturer Part Number: xr16l2552im
• Description: Industry Smallest Package Uart With 2.25v To 5.5v Operation
• Manufacturer: Exar Corporation

XR16L2552
2.25V TO 5.5V DUART WITH 16-BYTE FIFO
The on-chip oscillator is designed to use an industry standard microprocessor crystal (parallel resonant,
fundamental frequency with 10-22 pF capacitance load, ESR of 20-120 ohms and 100ppm frequency
tolerance) connected externally between the XTAL1 and XTAL2 pins (see
1 MΩ resistor across it. Alternatively, an external clock can be connected to the XTAL1 pin to clock the internal
baud rate generator for standard or custom rates. Typical oscillator connections are shown in
further reading on oscillator circuit please see application note DAN108 on EXAR’s web site.
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 operating with a crystal frequency of up to 24
MHz. However, with an external clock input on XTAL1 pin and a 2K ohms pull-up resistor on XTAL2 pin (as
shown in
5.0V.
2.11
Programmable Baud Rate Generator
Figure
5) it can extend its operation up to 64 MHz (4Mbps serial data rate) at room temperature and
F
F
IGURE
IGURE
vcc
gnd
22-47 pF
XTAL1
5. E
4. T
C1
External Clock
YPICAL OSCILLATOR CONNECTIONS
XTERNAL
500 KΩ − 1 MΩ
R1
2K
VCC
R2
22-47 pF
10
XTAL2
C
C2
Y1
LOCK
XTAL1
XTAL2
1.8432 MHz
C
(Optional)
0-120 Ω
24 MHz
ONNECTION FOR
R1
to
Figure
E
2), with an external 500kΩ to
XTENDED
D
xr
ATA
Figure
R
ATE
REV. 1.1.1
4. For