ATF1500AL-20JU

Overview

The ATF1500AL-20JU is a high-density, electrically erasable complex programmable logic device (CPLD) manufactured by Microchip Technology. It features 32 macrocells and up to 36 inputs within a 44-pin Plastic J-leaded Chip Carrier (PLCC) package. Built on advanced Flash technology, the device supports registered operation at speeds up to 125 MHz with a maximum pin-to-pin delay of 9 ns. It operates at a 5V supply voltage and includes automatic standby mode reducing current to 3 mA typical. The component is designed for industrial temperature ranges (-40°C to +85°C) and offers fully connected input and feedback logic arrays.

Feature Summary

• Advanced Flash Technology: Completely reprogrammable with 100 program/erase cycles and 20-year data retention.
• High Performance: Supports sequential logic up to 125 MHz with 7.5 ns to 9 ns propagation delays depending on configuration.
• Flexible Macrocell Architecture: Features D/T/Latch configurable flip-flops, global and individual register control signals, and programmable output slew rates.
• Power Management: Includes automatic 3 mA standby mode (ATF1500AL) and pin-controlled power-down mode reducing current to below 10 mA.

Applications

• Integration of TTL, SSI, MSI, and classic PLD logic functions.
• State machine initialization and control.
• Complex combinatorial and registered logic design.
• System noise reduction via programmable output slew rate control.

Procurement Notes

Verify the specific ordering suffix 'JU' corresponds to the 44-lead PLCC package and Industrial temperature range as defined in the official Microchip ordering guide. Confirm RoHS compliance status for the specific batch, noting that Green package options are available. Ensure design files account for the backward compatibility requirements with existing ATF1500/L software tools if migrating from legacy designs.

Selection Notes

Select this component when a 44-pin CPLD with 32 macrocells is required for industrial environments. The -20 speed grade provides a 9 ns max clock-to-output delay suitable for applications requiring up to 40 MHz external feedback frequency. Consider the ATF1500A variant if commercial temperature range (0°C to 70°C) suffices, or the ATF1502AS if higher speed performance is needed, as it is noted as a pin-compatible replacement for faster grades.

Part Context

The ATF1500A(L) series represents a family of high-performance EPLDs utilizing Flash memory technology. This architecture allows for unlimited reprogramming without the limitations of OTP devices. The ATF1500AL variant specifically emphasizes lower power consumption through automatic standby modes compared to the standard ATF1500A. The device is supported by third-party synthesis tools and maintains backward compatibility with earlier Atmel PLD design flows.

Replacement Considerations

The ATF1502AS is identified as a pin-compatible replacement for fast-speed grades. For other specifications, suggested replacements are available in Green packages. Verify pinout compatibility and electrical characteristics before substituting, as speed grades and temperature ranges may differ between the ATF1500AL and alternative models.

FAQ

What is the function of the PD pin?

The PD (Power-Down) pin controls an optional pin-controlled power-down mode. When driven high, it reduces supply current to below 10 mA and latches all internal logic states. In this mode, the PD pin cannot be used as a logic input or output.

How does the Pin-keeper feature work?

Programmable Pin-keeper circuits prevent unused Input and I/O pins from floating to intermediate voltage levels, which reduces unnecessary power consumption and system noise. If activated, the pin retains its last driven state when left floating, eliminating the need for external pull-up resistors.

What is the maximum operating frequency for internal feedback?

For the ATF1500AL-20JU, the maximum operating frequency with internal feedback is 71 MHz, calculated based on the setup time and clock-to-feedback delay parameters specified in the AC characteristics table.