IDT 89EBPES16NT2, Руководство пользователя

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IDT Installation of the EB16NT2 Eval Board
EB16NT2 Eval Board Manual 2 - 3 November 13, 2007
Notes
Power Sources
The EB16NT2 is powered from the upstream port slot power.
PCI Express Serial Data Transmit Termination Voltage Converter
A DC-DC converter (U6) provides a 1.5V PCI Express serial data transmit termination voltage (shown
as VPETVTT) to the PES16NT2.
PCI Express Digital Power Voltage Converter
A separate DC-DC converter (U3) provides a 1.0V PCI Express digital power voltage (VDDPE) to the
PES16NT2.
PCI Express Analog Power Voltage Converter
A separate DC-DC converter (7) provides a 1.0V PCI Express analog power voltage (shown as
VDDPEA) to the PES16NT2.
Core Logic Voltage Converter
A separate DC-DC converter (U1) provides the 1.0V core voltage (VDDCORE) to the PES16NT2.
3.3V I/O Power Module
A 12V to 3.3V power module (U26) provides the 3.3V I/O voltage (VDD_3V3) to the PES16NT2.
Power-up Sequence
The power-up sequence must be as following:
1. VDDIO - 3.3V
2. VDDCORE, VDDPEA, VDDPE - 1.0V
3. VTTPE - 1.5V
When powering up, each voltage level must ramp up and stabilize prior to applying the next voltage in
the sequence to ensure internal latch-up issues are avoided. There are no maximum time limitations
between sequential valid power level requirements. To insure that the sequencing requirements are met, a
0.015UF is used at the SOFTSTART cap on the VTTPE and VTTPEA voltage converter (U3 and U7 pin 36)
in the EB16NT2.
Required Jumpers
To deliver power to the PES16NT2 switch, the following jumpers must be shunted: W10, W22-W25.
These jumpers were implemented so that the power consumption of the PES16NT2 can be measured.
Reset
The PES16NT2 supports two types of reset mechanisms as described in the PCI Express specification:
– Fundamental Reset: This is a system-generated reset that propagates along the PCI Express
tree through a single side-band signal PERST# which is connected to the Root Complex, the
PES16NT2, and the endpoints.
– Hot Reset: This is an In-band Reset, communicated downstream via a link from one device to
another. Hot Reset may be initiated by software. This is further discussed in the 89HPES16NT2
User Manual. The EB16NT2 evaluation board provides seamless support for Hot Reset.