IDT EB8T5A Eval Board, Руководство пользователя

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IDT Installation of the EB8T5A Eval Board
EB8T5A Eval Board Manual 2 - 6 July 23, 2009
Notes
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 VTTPE or VPETVTT) to the PES8T5A.
PCI Express Digital Power Voltage Converter
A separate DC-DC converter (U16) provides a 1.0V PCI Express digital power voltage (VDDPE) to the
PES8T5A.
PCI Express Analog Power Voltage Converter
A separate DC-DC converter (U7) provides a 1.0V PCI Express analog power voltage (shown as
VDDAPE or VDDPEA) to the PES8T5A.
Core Logic Voltage Converter
A separate DC-DC converter (U1) provides the 1.0V core voltage (VDDCORE) to the PES8T5A.
3.3V I/O Power Module
A 12V to 3.3V power module (U5) provides the 3.3V I/O voltage (VDDIO) to the PES8T5A.
Power-up Sequence
The power-up sequence must be as following:
1. VDDIO - 3.3V
2. VDDCORE, VDDAPE, 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
0.047µF is used at the SOFTSTART cap on the VTTPE’s voltage converter (U6 pin 36) in the EB8T5A.
Required Jumpers
To deliver power to the PES8T5A switch, the following jumpers must be shunted: W4, W10, W23, W24,
and W25. These jumpers were implemented so that the power consumption of the PES8T5A can be
measured.
Reset
The PES8T5A 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
PES8T5A, 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 89HPES8T5A
User Manual. The EB8T5A evaluation board provides seamless support for Hot Reset.
Fundamental Reset
There are two types of Fundamental Resets which may occur on the EB8T5A evaluation board:
– Cold Reset: During initial power-on, the onboard voltage monitor (TLC7733D) will assert the PCI
Express Reset (PERSTN) input pin of the PES8T5A.
– Warm Reset: This is triggered by hardware while the device is powered on. Warm Reset can be
initiated by two methods:
• Pressing a push-button switch (S1) located on EB8T5A board