EP220 & EP224 Classic EPLDs
The XORgate can implement active-high or active-low logic, and can use
DeMorgan’s inversion to reduce the number of product terms needed to
implement a function.
If the EP220 and EP224 register outputs do not require an OEsignal, the
internal product term can hold the output in an enabled state; if a global
OEsignal is required, any input can be dedicated to the task, and all eight
product terms can be programmed accordingly.
High-Frequency, Low-Skew Global Clock
EP220 and EP224 devices have extremely low output-pin skew: registered
output skew (t
) is typically less than 300 ps; combinatorial output
OCR
skew (t
) is typically less than 400 ps. This low output-skew rate makes
OSC
EP220 and EP224 devices ideal for high-frequency system Clock
applications, including Intel Pentium microprocessors, 486-based PCs,
and PCI bus designs.
The EP220 and EP224 devices are a logical superset of most high-speed,
24-pin PAL/GAL devices. Industry-standard JEDEC Files from
compatible devices can be programmed into EP220 or EP224 devices.
Table 1 summarizes some of the devices that can be replaced or upgraded
with EP220 and EP224 devices.
PLD
Compatibility
Table 1. EP220- and EP224-Compatible Devices (Part 1 of 4)
PAL/GAL Vendor
PAL/GAL Device
Altera Replacement
Device
Speed
Grade
Advanced Micro
Devices
PAL16L8
EP220-7
EP224-7
EP220-10
EP224-10
-7
PAL16R8
PALCE16V8
PAL20L8
PAL20R8
PALCE20V8
PAL16L8
-10
PAL16R8
PALCE16V8
PAL20L8
PAL20R8
PALCE20V8
Altera Corporation
5
ALTERA [ ALTERA CORPORATION ]
