XC3S400-4FT256C Xilinx Inc, XC3S400-4FT256C Datasheet - Page 105

• Manufacturer Part Number: XC3S400-4FT256C
• Description: SEMI CONDUCTOR
• Manufacturer: Xilinx Inc

Specifications of XC3S400-4FT256C

• Case: BGA
• Dc: 04+

DUAL Type: Dual-Purpose Configuration and
I/O Pins
These pins serve dual purposes. The user-I/O pins are tem-
porarily borrowed during the configuration process to load
configuration data into the FPGA. After configuration, these
pins are then usually available as a user I/O in the applica-
tion. If a pin is not applicable to the specific configuration
mode—controlled by the mode select pins M2, M1, and
M0—then the pin behaves as an I/O-type pin.
There are 12 dual-purpose configuration pins on every
package, six of which are part of I/O Bank 4, the other six
part of I/O Bank 5. Only a few of the pins in Bank 4 are used
in the Serial configuration modes.
See
DS099-4 (v2.2) May 25, 2007
Product Specification
“Pin Behavior During Configuration, page 114”.
R
Bank 5
Bank 0
Bank 4
Bank 1
Figure 38: Differential Pair Labelling
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Serial Configuration Modes
This section describes the dual-purpose pins used during
either Master or Slave Serial mode. See
Select pin settings required for Serial modes. All such pins
are in Bank 4 and powered by VCCO_4.
In both the Master and Slave Serial modes, DIN is the serial
configuration data input. The D1-D7 inputs are unused in
serial mode and behave like general-purpose I/O pins.
In all the cases, the configuration data is synchronized to
the rising edge of the CCLK clock signal.
The DIN, DOUT, and INIT_B pins can be retained in the
application to support reconfiguration by setting the Persist
bitstream generation option. However, the serial modes do
not support device readback.
IO_L38P_2
IO_L38N_2
IO_L39P_2
IO_L39N_2
Spartan-3 FPGA Family: Pinout Descriptions
Negative Polarity,
Inverted Driver
Positive Polarity,
Pair Number
True Driver
DS099-4_01_042303
Bank Number
Table 74
for Mode
105