peel22cv10aj-5 ETC-unknow, peel22cv10aj-5 Datasheet - Page 4

• Manufacturer Part Number: peel22cv10aj-5
• Description: Peel?22cv10a -5/-7/-10/-15/l-15/-25 Cmos Programmable Electrically Erasable Logic
• Manufacturer: ETC-unknow

enable the output buffer and yield a dedicated out-
put. Conversely, if every connection is intact, the
enable term will always be logically false and the
I/O will function as a dedicated input.
Input/Feedback Select
When configuring an I/O macrocell to implement a
registered function (configurations 1 and 2 in Figure
5), the Q output of the flip-flop drives the feedback
term. When configuring an I/O macrocell to imple-
ment a combinatorial function (configurations 3 and
4 in Figure 5), the feedback signal is taken from the
I/O pin. In this case, the pin can be used as a
dedicated input or a bi-directional I/O. (Refer also
to Table 1.)
Additional Macro Cell Configurations
Besides the standard four-configuration macrocell
shown in Figure 5, each PEEL22CV10A provides
an additional eight configurations that can be used
to increase design flexibility. The configurations are
the same provided by the PEEL18CV8 and
PEEL22CV10AZ. However, to maintain JEDEC file
compatibility with standard 22V10 PLDs the addi-
tional configurations can only be utilized by specify-
Figure 4. Block Diagram of the PEEL22CV10A I/O Macrocell
3 - 54
ing the PEEL22CV10A+ for logic assembly and pro-
gramming. To reference these additional configura-
tions please refer to the PEEL22CV10A+ specifica-
tions at the end of this data sheet.
Design Security
The PEEL22CV10A provides a special EEPROM
security bit that prevents unauthorized reading or
copying of designs programmed into the device.
The security bit is set by the PLD programmer,
either at the conclusion of the programming cycle
or as a separate step after the device has been
programmed. Once the security bit is set, it is im-
possible to verify (read) or program the PEEL until
the entire device has first been erased with the
bulk-erase function.
Signature Word
The signature word feature allows a 24-bit code to
be programmed into the PEEL22CV10A if the
PEEL22CV10A+ software option is used. The code
can be read back even after the security bit has
been set. The signature word can be used to iden-
tify the pattern programmed into the device or to
record the design revision, etc.
PEEL 22CV10A