XR17C158CV-F Exar Corporation, XR17C158CV-F Datasheet - Page 23

• Manufacturer Part Number: XR17C158CV-F
• Description: IC UART PCI BUS 5V OCTAL 144LQFP
• Manufacturer: Exar Corporation
• Type: Universal PCI Bus Octal UARTr

Specifications of XR17C158CV-F

• Number Of Channels: 8
• Package / Case: 144-LQFP
• Features: *
• Fifo's: 64 Byte
• Protocol: RS485
• Voltage - Supply: 5V
• With Auto Flow Control: Yes
• With Irda Encoder/decoder: Yes
• With False Start Bit Detection: Yes
• With Modem Control: Yes
• Mounting Type: Surface Mount
• Data Rate: 6.25 Mbps
• Supply Voltage (max): 7 V
• Supply Current: 5 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Operating Supply Voltage: 7 V
• No. Of Channels: 8
• Uart Features: High Performance, Read/Write Burst Operation
• Supply Voltage Range: -0.5V To 7V
• Operating Temperature Range: 0°C To +70°C
• 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: 1016-1287

xr
REV. 1.4.3
The 158 includes an on-chip oscillator (XTAL1 and XTAL2). The crystal oscillator provides the system clock to
the Baud Rate Generators (BRG) in each of the 8 UARTs, the 16-bit general purpose timer/counter and inter-
nal logics. XTAL1 is the input to the oscillator or external clock buffer input with XTAL2 pin being the output.
See Programmable Baud Rate Generator in the UART section for programming details.
The on-chip oscillator is designed to use an industry standard microprocessor crystal (parallel resonant with
10-22 pF capacitance load, 100ppm) connected externally between the XTAL1 and XTAL2 pins (see
Alternatively, an external clock can be connected to the XTAL1 pin to clock the internal 8 baud rate generators
for standard or custom rates. However, for external clock frequencies greater than 24MHz, a 2K pull-up may be
necessary on the XTAL2 output (see
ther reading on oscillator circuit please see application note DAN108 on EXAR’s web site.
2.0 CRYSTAL OSCILLATOR / BUFFER
F
IGURE
F
IGURE
7. T
Figure
vcc
gnd
YPICAL OSCILLATOR CONNECTIONS
8. E
22-47pF
XTAL1
External Clock
C1
8). Typical oscillator connections are shown in
XTERNAL
R=300K to 400K
R1
2K
14.7456
VCC
MHz
23
C
LOCK
22-47pF
XTAL2
XTAL1
XTAL2
C2
C
ONNECTION FOR
E
5V PCI BUS OCTAL UART
XTENDED
D
Figure
ATA
R
XR17C158
ATE
Figure
7. For fur-
7).