GAL20V8QS-15QNC

Programmable Logic Device Pld Overview

The GAL20V8QS-15QNC is a CMOS Electrically Erasable Programmable Logic Device (EE PLD) manufactured by National Semiconductor, now part of Texas Instruments. It features a PAL-type architecture with 20 input lines and 8 output lines housed in a 28-pin Plastic Quad Flat Package (PQCC). The device operates with a maximum propagation delay of 15 ns and supports a maximum clock frequency of approximately 47 MHz. Key structural elements include eight macrocells, shared input/clock capabilities, and register preload functionality, designed for low-noise digital logic applications.

Programmable Logic Device Pld Feature Summary

• CMOS technology ensuring low power consumption and minimal noise generation
• PAL-type architecture with 20 inputs and 8 outputs
• Eight macrocells with shared input and clock lines
• Register preload capability for flexible state management

Programmable Logic Device Pld Applications

• Digital logic replacement for discrete gate circuits
• Address decoding and memory mapping systems
• State machine implementation in embedded controllers
• Signal routing and protocol conversion interfaces

Programmable Logic Device Pld Procurement Notes

Verify the manufacturer lineage, as National Semiconductor assets were acquired by Texas Instruments. Confirm the specific package variant matches the PQCC-28 specification. Ensure compatibility with existing programming tools for EE PLDs. Check for RoHS compliance status if required by current assembly standards. Validate that the 15 ns speed grade meets system timing requirements.

Programmable Logic Device Pld Selection Notes

Select this component when a reprogrammable solution is needed to replace fixed PALs or gates. The 15 ns delay suits moderate-speed digital designs. Consider the 28-pin PQCC package for surface-mount assembly constraints. Verify voltage supply requirements against the system's 5V or 3.3V rails. Ensure the programming infrastructure supports EE PLD erasure and reconfiguration cycles.

Programmable Logic Device Pld Part Context

This device belongs to the GAL20V8 family of programmable logic devices. It serves as a direct upgrade path from older fuse-programmable PALs due to its electrically erasable nature. The QS suffix typically denotes a commercial temperature range and specific packaging. It is functionally compatible with other GAL20V8 variants differing only in speed grades or package types.

Programmable Logic Device Pld Replacement Considerations

Direct pin-compatible substitutes include GAL20V8-15LVI and GAL20V8A-10JC from various manufacturers like Lattice or TI. Verify electrical parameters such as propagation delay and I/O drive strength. Ensure the replacement supports the same programming voltage and algorithm. Check package dimensions for mechanical fit in existing footprints.