XR16L2750IM-F Exar Corporation, XR16L2750IM-F Datasheet - Page 10

• Manufacturer Part Number: XR16L2750IM-F
• Description: IC UART FIFO 64B DUAL 48TQFP
• Manufacturer: Exar Corporation
• Type: IrDA or RS- 485r

Specifications of XR16L2750IM-F

• Number Of Channels: 2, DUART
• Package / Case: 48-TQFP
• Features: *
• Fifo's: 64 Byte
• Protocol: RS232, RS485
• Voltage - Supply: 2.25 V ~ 5.5 V
• With Auto Flow Control: Yes
• With Irda Encoder/decoder: Yes
• With False Start Bit Detection: Yes
• With Modem Control: Yes
• With Cmos: Yes
• Mounting Type: Surface Mount
• Data Rate: 6.25 Mbps
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.25 V
• Supply Current: 5 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 2.5 V or 3.3 V or 5 V
• No. Of Channels: 2
• Uart Features: Tx/Rx FIFO Counters
• Supply Voltage Range: 2.25V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: TQFP
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 1016-1280

XR16L2750
2.25V TO 5.5V DUART WITH 64-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 100 ppm frequency
tolerance) connected externally between the XTAL1 and XTAL2 pins (see
Rate Generator is capable of operating with a crystal oscillator 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
extend its operation up to 50 MHz (6.25 Mbps serial data rate) at 5V with an 8X sampling rate.
For further reading on the oscillator circuit please see the Application Note DAN108 on the EXAR web site at
http://www.exar.com.
Each UART has its own Baud Rate Generator (BRG) with a prescaler. The prescaler is controlled by a
software bit in the MCR register. The MCR register bit-7 sets the prescaler to divide the input crystal or external
clock by 1 or 4. The clock output of the prescaler goes to the BRG. The BRG further divides this clock by a
programmable divisor between 1 and (2
sampling rate clock is used by the transmitter for data bit shifting and receiver for data sampling. The BRG
divisor defaults to the maximum baud rate (DLL = 0x01 and DLM = 0x00) upon power up.
Programming the Baud Rate Generator Registers DLM and DLL provides the capability of selecting the
operating data rate.
clock at 16X sampling rate clock rate. A 16X sampling clock is typically used. However, user can select the 8X
2.10
Programmable Baud Rate Generator
F
IGURE
XTAL1
XTAL2
Table 5
6. B
AUD
shows the standard data rates available with a 14.7456 MHz crystal or external
R
Crystal
Buffer
Osc/
ATE
F
IGURE
G
vcc
gnd
ENERATOR AND
16
5. E
-1) to obtain a 16X sampling rate clock of the serial data rate. The
External Clock
Divide by 4
Divide by 1
XTERNAL
Prescaler
Prescaler
R1
2K
VCC
P
10
RESCALER
C
LOCK
MCR Bit-7=0
MCR Bit-7=1
(default)
XTAL1
XTAL2
C
ONNECTION FOR
Baud Rate
DLL and DLM
Generator
Registers
Logic
Figure
E
Rate Clock to
4). The programmable Baud
XTENDED
Transmitter
Sampling
16X
D
xr
ATA
Figure
R
ATE
REV. 1.2.1
5) it can