ATF16V8BQ ATMEL Corporation, ATF16V8BQ Datasheet - Page 6

• Manufacturer Part Number: ATF16V8BQ
• Description: High- Performance Flash PLD
• Manufacturer: ATMEL Corporation

Electronic Signature Word
There are 64 bits of programmable memory that are always
available to the user, even if the device is secured. These
bits can be used for user-specific data.
Programming/Erasing
Programming/erasing is performed using standard PLD
programmers. See CMOS PLD Programming Hardware
and Software Suppor t for information on software/program-
ming.
Input Diagram
Functional Logic Diagram Description
The Logic Option and Functional Diagrams describe the
ATF16V8B architecture. Eight configurable macrocells can
be configured as a registered output, combinatorial I/O,
combinatorial output, or dedicated input.
The ATF16V8B can be configured in one of three different
modes. Each mode makes the ATF16V8B look like a differ-
ent device. Most PLD compilers can choose the right
mode automatically. The user can also force the selection
by supplying the compiler with a mode selection. The deter-
mining factors would be the usage of register versus com-
binatorial outputs and dedicated outputs versus outputs
with output enable control.
The ATF16V8B universal architecture can be programmed
to emulate many 20-pin PAL devices. These architectural
Compiler Mode Selection
Note:
6
ABEL, Atmel-ABEL
CUPL
LOG/iC
OrCAD-PLD
PLDesigner
Tango-PLD
1. Only applicable for version 3.4 or lower.
ATF16V8B
Registered
P16V8R
G16V8MS
GAL16V8_R
“Registered”
P16V8R
G16V8R
(1)
Complex
P16V8C
G16V8MA
GAL16V8_C7
“Complex”
P16V8C
G16V8C
Input and I/O Pull-Ups
All ATF16V8B family members have internal input and I/O
pull-up resistors. Therefore, whenever inputs or I/Os are
not being driven externally, they will float to V
ensures that all logic array inputs are at known states.
These are relatively weak active pull-ups that can easily be
overdriven by TTL-compatible drivers (see input and I/O
diagrams below).
I/O Diagram
subsets can be found in each of the configuration modes
described in the following pages. The user can download
the listed subset device JEDEC programming file to the
PLD programmer, and the ATF16V8B can be configured to
act like the chosen device. Check with your programmer
manufacturer for this capability.
Unused product terms are automatically disabled by the
compiler to decrease power consumption. A Security Fuse,
when programmed, protects the content of the ATF16V8B.
Eight bytes (64 fuses) of User Signature are accessible to
the user for purposes such as storing project name, part
number, revision, or date. The User Signature is accessible
regardless of the state of the Security Fuse.
(1)
Simple
P16V8AS
G16V8AS
GAL16V8_C8
“Simple”
P16V8C
G16V8AS
(1)
Auto Select
P16V8
G16V8
GAL16V8
GAL16V8A
P16V8A
G16V8
CC
. This