ATF2500C-20PU Atmel, ATF2500C-20PU Datasheet - Page 7

• Manufacturer Part Number: ATF2500C-20PU
• Description: IC CPLD EE 20NS 40DIP
• Manufacturer: Atmel
• Series: ATF2500C(L)r

Specifications of ATF2500C-20PU

• Programmable Type: In System Programmable
• Delay Time Tpd(1) Max: 20.0ns
• Voltage Supply - Internal: 4.5 V ~ 5.5 V
• Number Of Macrocells: 24
• Number Of I /o: 24
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 40-DIP (0.600", 15.24mm)
• Voltage: 5V
• Memory Type: EEPROM
• Number Of Product Terms Per Macro: 12
• Maximum Operating Frequency: 71 MHz
• Delay Time: 20 ns
• Number Of Programmable I/os: 24
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: Through Hole
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4.5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Number Of Logic Elements/cells: -
• Lead Free Status / Rohs Status: Details

7. Security Fuse Usage
8. Bus-friendly Pin-keeper Input and I/O
0777K–PLD–1/24/08
A single fuse is provided to prevent unauthorized copying of ATF2500C fuse patterns. Once pro-
grammed, the outputs will read programmed during verify.
The security fuse should be programmed last, as its effect is immediate.
The security fuse also inhibits Preload and Q2 observability.
All ATF2500C family members have programmable internal input and I/O pin-keeper circuits.
The default condition, including when using the AT2500C/CQ family to replace the AT2500B/BQ
or AT2500H, is that the pin-keepers are not activated.
When pin-keepers are active, inputs or I/Os not being driven externally will maintain their last
driven state. This ensures that all logic array inputs and device outputs are known states. Pin-
keepers are relatively weak active circuits that can be easily overridden by TTL-compatible driv-
ers (see input and I/O diagrams below).
Enabling or disabling of the pin-keeper circuits is controlled by the device type chosen in the
logic compiler device selection menu. Please refer to the Software Compiler Mode Selection
table for more details. Once the pin-keeper circuits are disabled, normal termination procedures
required for unused inputs and I/Os.
Figure 8-1.
Input Diagram
PROGRAMMABLE
OPTION
ATF2500C
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