PSD4235G2-90UI

Overview

The PSD4235G2-90UI is a Flash in-system programmable (ISP) Programmable System Device designed for 16-bit microcontrollers with a 5 V supply. It integrates 4 Mbit Primary Flash, 256 Kbit Secondary Flash, and 64 Kbit SRAM. The device includes over 3000 PLD gates, supporting CPLD and DPLD configurations. It features 52 individually configurable I/O pins across seven ports. Memory access time is 70 ns. The component operates on a single 5 V ± 10% supply and supports concurrent read/erase/write operations.

Feature Summary

• Dual bank Flash memories: 4 Mbit Primary (8 sectors) and 256 Kbit Secondary (4 sectors) with concurrent operation capability
• Integrated PLD with over 3000 gates, including 16 output macrocells and 24 input macrocells
• In-system programming via JTAG serial port for full-chip programmability
• Internal page register to expand MCU address space by a factor of 256

Applications

• 16-Bit MCU Peripherals
• Motorola 80C196 Series Systems
• Intel MCS-96 Series Systems

Procurement Notes

Verify the specific suffix 'U' against official STMicroelectronics documentation to confirm package type and environmental compliance details. Confirm current production status as legacy components may be discontinued or subject to last-time buy restrictions. Ensure compatibility with existing PCB footprints for the 80-LQFP package.

Selection Notes

Select this component for designs requiring high-density memory expansion and complex logic integration for 16-bit MCUs. The 70 ns speed suits applications needing fast memory access. Verify that the target MCU supports the required bus interface protocols and that the 5 V supply voltage aligns with the system power architecture.

Part Context

This part belongs to the PSD4235G2 series of Programmable System Devices from STMicroelectronics. These devices are engineered to replace discrete memory and logic chips, reducing board space and complexity. The -90 variant denotes the 70 ns speed grade within the LQFP80 package family.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided source material.