PI7C9X7954AFDE Pericom Semiconductor, PI7C9X7954AFDE Datasheet - Page 23

• Manufacturer Part Number: PI7C9X7954AFDE
• Description: IC PCIE-TO-UART BRIDGE 128LQFP
• Manufacturer: Pericom Semiconductor

Specifications of PI7C9X7954AFDE

• Applications: PCIe-to-Uart Bridge
• Interface: Advanced Configuration Power Interface (ACPI)
• Voltage - Supply: 1.8V, 3.3V
• Package / Case: 128-LQFP
• Mounting Type: Surface Mount
• Transmitter And Receiver Fifo Counter: Yes
• Package Type: LQFP
• Mounting: Surface Mount
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5.2.11. Crystal Oscillator
The PI7C9X7954 uses a crystal oscillator or an external clock source to provide system clock to the Baud
Rate Generator. When a clock source is used, the clock signal should be connected to the XTLI pin, and a
2K pull-up resistor should be connected to the XTLO pin.
When a crystal oscillator is used, the XTLI is the input and XTLO is the output, and the crystal should be
connected in parallel with two capacitors.
September 2009 – Revision 1.3
Pericom Semiconductor
Figure 5-4 External Clock Source as the Clock Source
VCC
GND
Figure 5-3 Crystal Oscillator as the Clock Source
09-0088
External Clock
XTLI
C1
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14.7456 MHz
R1
2K
VCC
R
C2
XTLO
XTLI
XTLO
PCI Express® Quad UART
PI7C9X7954
Datasheet