ATF1504BE ATMEL Corporation, ATF1504BE Datasheet - Page 6

• Manufacturer Part Number: ATF1504BE
• Description: High Speed CPLD
• Manufacturer: ATMEL Corporation

Figure 1-4.
1.1
1.2
6
Product Terms and Select Mux
OR/XOR/CASCADE Logic
ATF1504BE
ATF1504BE Macrocell
Each ATF1504BE macrocell has five product terms. Each product term receives as its inputs all
signals from both the global bus and regional bus.
The product term select multiplexer (PTMUX) allocates the five product terms as needed to the
macrocell logic gates and control signals. The PTMUX programming is determined by the design
compiler, which selects the optimum macrocell configuration.
The ATF1504BE’s logic structure is designed to efficiently support all types of logic. Within a sin-
gle macrocell, all the product terms can be routed to the OR gate, creating a 5-input AND/OR
sum term. With the addition of the CASIN from neighboring macrocells, this can be expanded to
as many as 40 product terms with minimal additional delay.
The macrocell’s XOR gate allows efficient implementation of compare and arithmetic functions.
One input to the XOR comes from the OR sum term. The other XOR input can be a product term
or a fixed high or low level. For combinatorial outputs, the fixed level input allows polarity selec-
tion. For registered functions, the fixed levels allow DeMorgan minimization of product terms.
BURIED FEEDBACK
TRIGGER
SCHMITT
3637A–PLD–11/06