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Preliminary Data Sheet, Rev. 1
September 1998
ORCA Series 3 FPGAs
Lucent Technologies Inc.
95
FPGA Configuration Modes (continued)
Daisy-Chaining with Boundary Scan
Multiple FPGAs can be configured through the JTAG ports by using a daisy-chain of the FPGAs. This daisy-chain-
ing operation is available upon initial configuration after powerup, after a power-on reset, after pulling the program
pin to reset the chip, or during a reconfiguration if the EN_JTAG RAM has been set.
All daisy-chained FPGAs are connected in series. Each FPGA reads and shifts the preamble and length count in
on the positive TCK and out on the negative TCK edges.
An upstream FPGA that has received the preamble and length count outputs a high on TDO until it has received
the appropriate number of data frames so that downstream FPGAs do not receive frame start bit pairs. After load-
ing and retransmitting the preamble and length count to a daisy-chain of downstream devices, the lead device
loads its configuration data frames.
The loading of configuration data continues after the lead device had received its configuration read into TDI of
downstream devices on the positive edge of TCK, and shifted out TDO on the negative edge of TCK. Figure 63
shows the connections for loading multiple FPGAs in a JTAG daisy-chain configuration.
Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. These are abso-
lute stress ratings only. Functional operation of the device is not implied at these or any other conditions in excess
of those given in the operations sections of this data sheet. Exposure to absolute maximum ratings for extended
periods can adversely affect device reliability.
The
ORCA Series FPGAs include circuitry designed to protect the chips from damaging substrate injection cur-
rents and to prevent accumulations of static charge. Nevertheless, conventional precautions should be observed
during storage, handling, and use to avoid exposure to excessive electrical stress.
Table 34. Absolute Maximum Ratings
Recommended Operating Conditions
Table 35. Recommended Operating Conditions
Note: The maximum recommended junction temperature (TJ) during operation is 125 °C.
Parameter
Symbol
Min
Max
Unit
Storage Temperature
Tstg
–65
150
°C
Supply Voltage with Respect to Ground
VDD
–0.5
7.0
V
Input Signal with Respect to Ground
—
–0.5
VDD + 0.3
V
Signal Applied to High-impedance Output
—
–0.5
VDD + 0.3
V
Maximum Package Body Temperature
—
220
°C
Mode
OR3Cxx
OR3Txxx
Temperature
Range
(Ambient)
Supply Voltage
(VDD)
Temperature
Range
(Ambient)
Supply Voltage
(VDD)
Commercial
0 °C to 70 °C
5 V ± 5%
0 °C to 70 °C
3.0 V to 3.6 V
Industrial
–40 °C to +85 °C
5 V ± 10%
–40 °C to +85 °C
3.0 V to 3.6 V