PSD4235G2-90U

Overview

The PSD4235G2-90U is a Flash in-system programmable (ISP) peripheral IC designed for 16-bit microcontrollers with a 5 V supply. It integrates 4 Mbit Primary Flash and 256 Kbit Secondary Flash, supporting concurrent read/write operations. The device includes 64 Kbit SRAM, over 3000 PLD gates (CPLD/DPLD), and 7 I/O ports providing 52 configurable pins. It features JTAG-based ISP, a page register for address expansion, and power management capabilities. The component operates at 70 ns access times and is housed in an 80-LQFP package.

Feature Summary

• Dual-bank Flash memory: 4 Mbit Primary and 256 Kbit Secondary with concurrent operation capability
• Integrated PLD with over 3000 gates, including 16 output macrocells and user-defined internal chip select decoding
• In-system programming via JTAG serial port for full-chip programmability
• Page register expands microcontroller address space by a factor of 256

Applications

• 16-bit MCU peripheral integration
• Complex memory mapping and separate program/data space configurations
• In-circuit programming and testing environments

Procurement Notes

Verify the specific ordering suffix 'U' against the manufacturer's documentation to confirm packaging details, as datasheets may list standard LQFP80 without explicit suffix differentiation. Confirm availability status, as this series may be discontinued or superseded by newer generations. Ensure compatibility with 5 V supply requirements and 16-bit bus interfaces during procurement planning.

Selection Notes

Select this component when designing systems requiring simultaneous Flash erasure/writing and reading. It is suitable for applications needing extensive PLD logic for custom chip select decoding alongside large memory capacity. Verify that the target 16-bit MCU supports the required bus interface protocols and that the 5 V supply voltage aligns with the system design constraints.

Part Context

The PSD4235G2 belongs to STMicroelectronics' Programmable System Device (PSD) family, which combines Flash memory, SRAM, and PLD logic into a single chip. This integration reduces board space and simplifies design compared to discrete components. The G2 variant specifically targets 5 V 16-bit microcontroller architectures, offering high endurance and flexible configuration options for embedded control applications.

Replacement Considerations

Check for updated PSD series devices from STMicroelectronics that offer enhanced performance or different voltage levels. Verify pinout compatibility if substituting with other PSD models. Consult official replacement guides for any end-of-life notifications regarding the PSD4235G2 series.