Element | XC3000 | XC4000E | XC4000X | XC5200 | XC9000 | Spartan | SpartanXL | Virtex |
---|---|---|---|---|---|---|---|---|
WAND1 | N/A | Primitive | Primitive | N/A | N/A | N/A | N/A | N/A |
WAND4, WAND8. WAND16 | N/A | Macro | Macro | N/A | N/A | N/A | N/A | N/A |
WAND1, WAND4, WAND8, and WAND16 are single and multiple open-drain buffers. Each buffer has an input (I) and an open-drain output (O). When any of the inputs is Low, the output is Low. When all the inputs are High, the output is off. To obtain a High output, add pull-up resistors to the output (O). One pull-up resistor uses the least power, and two pull-up resistors achieve the fastest Low-to-High transition.
To indicate two pull-up resistors, add a DOUBLE parameter to the pull-up symbol attached to the output (O) node. Refer to the appropriate CAE tool interface user guide for details.
Figure 10.11 WAND8 Implementation XC4000 |