ATF1504ASL-20AC44 Equivalent & Substitute Parts

Part Overview

The ATF1504ASL-20AC44 is a 64-macrocell Complex Programmable Logic Device (CPLD) manufactured by Microchip Technology, housed in a 44-pin TQFP surface-mount package. This device features in-system programmability with a maximum propagation delay of 20 nanoseconds and operates within a 4.75V to 5.25V supply voltage range. The part is classified as obsolete, necessitating identification of functionally equivalent alternatives for new designs or production continuity.

Substiute Parts

ATF1504ASL-20AC44

Microchip TechnologyIn Stock: 4468ATF1504ASL-20AC44 Datasheet

Current PartRFQ

ATF1504ASL-25AU44

Microchip TechnologyIn Stock: 1939ATF1504ASL-25AU44 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the ATF1504ASL-20AC44 is determined by the following critical parameters:

• Macrocell Count: Must remain 64 to maintain logic capacity
• I/O Pin Count: Must remain 32 to preserve I/O functionality
• Package Type: Must remain 44-TQFP to ensure PCB compatibility
• Programmable Type: Must support in-system programmability
• Manufacturer: Microchip Technology ATF15xx series maintains design compatibility

The ATF1504ASL-25AU44 qualifies as a direct substitute based on identical macrocell count, I/O pin count, package configuration, and programmable architecture. Differences in propagation delay, voltage supply range, operating temperature, and compliance status are secondary parameters that must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The ATF1504ASL-25AU44 is the direct substitute for the obsolete ATF1504ASL-20AC44. Selection criteria are based on the following factors:

Product Status: The ATF1504ASL-25AU44 maintains active product status, ensuring continued availability and manufacturing support, whereas the ATF1504ASL-20AC44 is obsolete.

Compliance: The ATF1504ASL-25AU44 is ROHS3 compliant, meeting current regulatory requirements for new designs. The ATF1504ASL-20AC44 is RoHS non-compliant.

Electrical Compatibility: Both devices share identical macrocell architecture, I/O configuration, and programmable characteristics. The substitute operates across a wider voltage supply range (4.5V ~ 5.5V versus 4.75V ~ 5.25V) and extended temperature range (-40°C ~ 85°C versus 0°C ~ 70°C), providing greater operational flexibility.

Timing Consideration: The substitute exhibits a maximum propagation delay of 25 nanoseconds compared to 20 nanoseconds in the original part. Applications with timing-critical paths must verify that the 5-nanosecond increase in delay does not violate system timing constraints.

Frequently Asked Questions (FAQ)

Q: Can the ATF1504ASL-25AU44 directly replace the ATF1504ASL-20AC44 in existing designs?

A: Yes, from a functional and physical standpoint. Both devices share identical macrocell count (64), I/O pin count (32), package configuration (44-TQFP), and in-system programmability. However, the 5-nanosecond increase in maximum propagation delay must be evaluated against application timing requirements.

Q: What is the significance of the voltage supply range difference?

A: The ATF1504ASL-25AU44 operates across 4.5V ~ 5.5V, compared to 4.75V ~ 5.25V for the ATF1504ASL-20AC44. The wider range of the substitute provides greater tolerance to supply voltage variations and is compatible with systems operating at the original part's specified voltage window.

Q: Why is the operating temperature range different?

A: The ATF1504ASL-25AU44 supports -40°C ~ 85°C operation, extending below and above the original part's 0°C ~ 70°C range. This expanded range accommodates industrial and extended-temperature applications without requiring alternative components.

Q: Does the RoHS compliance difference affect substitution?

A: The ATF1504ASL-25AU44 is ROHS3 compliant, meeting current environmental and regulatory standards. The original part is RoHS non-compliant. For new designs or applications subject to RoHS requirements, the substitute is the appropriate selection.

Q: Are there any package or pinout differences?

A: No. Both devices use identical 44-TQFP (10x10) surface-mount packaging with 32 I/O pins. PCB layout and footprints are directly compatible.

Q: What is the impact of the 5-nanosecond timing difference?

A: The substitute's 25-nanosecond maximum propagation delay is 5 nanoseconds slower than the original 20-nanosecond specification. This difference must be evaluated within the context of system timing budgets. Applications with timing margins greater than 5 nanoseconds are unaffected. Time-critical designs require detailed timing analysis to confirm compatibility.