Powerdown - Xilinx Virtex-4 RocketIO User Manual

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Table 4-6: PLL/Data Frequency Divergence as a Function of Lock and Hysteresis

POWERDOWN

POWERDOWN, RXPD, and TXPD are used to reduce power.
show the definitions of POWERDOWN, RXPD, and TXPD.
Table 4-7: RocketIO Transceiver Power Control Description
POWERDOWN is a single-bit primitive port (see
off the MGT in case it is not needed for the design or is not transmitting or receiving for a
long period of time. When POWERDOWN is asserted, the PCS does not use any power.
The PCS clocks are disabled and do not propagate through the core. During
POWERDOWN, the current to TXP/TXN is turned off. The 50Ω connection to V
always connected, creating the termination value. Any given MGT that is not instantiated
in the design is automatically set to the POWERDOWN state by the Xilinx ISE®
development software and consumes no power.
Table 4-8: PMA Receiver Power Control Description
Virtex-4 RocketIO MGT User Guide
UG076 (v4.1) November 2, 2008
000
Lock Counter
(±4)
16,384 0.024%
000
8,192 0.049%
001
4,096 0.098%
010
2,048 0.195%
011
1,024 0.391%
100
512 0.781%
101
256 1.563%
110
128 3.125%
111
POWERDOWN
0
1
RXPD
TRUE
FALSE
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Hysteresis
001 010 011
(±8) (±16) (±32)
0.049% 0.098% 0.195%
0.098% 0.195% 0.391%
0.195% 0.391% 0.781%
0.391% 0.781% 1.563%
0.781% 1.563% 3.125%
1.563% 3.125% 6.250%
3.125% 6.250% 12.50%
6.250% 12.50% 25%
Function
PCS and PMA function normally.
PCS is in power down mode.
Table 1-7, page
Function
Powerdown the receiver.
Normal receiver operation.
Special Analog Functions
100 101 110
(±64) (±128) (±256)
0.391% 0.781% 1.563%
0.781% 1.563% 3.125%
1.563% 3.125% 6.250%
3.125% 6.250% 12.50%
6.250% 12.50% 25%
12.50% 25% 50%
25% 50% 100%
Disable
50% 100%
Lock=1
Table 4-7 through Table 4-9
47) that allows shutting
TTX
111
(±512)
3.125%
6.250%
12.50%
25%
50%
100%
Disable
Lock=0
Disable
Lock=0
is
151