Infineon Technologies CYDMX128B16-65BVXI

Overview

CYDMX128B16-65BVXI from Infineon Technologies (formerly Cypress) is an 8K × 16 asynchronous dual-port static RAM with true independent port access, 65 ns ADM interface timing, 1.8 V/2.5 V/3.0 V port-independent I/O support, and integrated mailbox interrupt logic. It enables real-time interprocessor communication in embedded control systems requiring deterministic memory arbitration and low-power operation across industrial temperature range.

For engineers reviewing the CYDMX128B16-65BVXI datasheet, CYDMX128B16-65BVXI pinout, CYDMX128B16-65BVXI application, or CYDMX128B16-65BVXI equivalent, key selection criteria include dual-port arbitration behavior, byte-selectable 16-bit data width, BGA-100 package compatibility, and port-specific power-down capability under mixed-voltage I/O conditions.

Technical Context

This device implements a true dual-ported SRAM architecture with one fixed ADM (address/data multiplexed) port and one configurable port supporting either standard SRAM or ADM mode via MSEL pin. Each port has independent CS#, WE#, OE#, UB#/LB#, BUSY#, and INT# signals, enabling concurrent read/write operations without external arbitration logic.

On-chip arbitration resolves address collisions by asserting BUSY# on the losing port within 4.5 ns (tBLA), while mailbox interrupts use dedicated upper memory locations (0x1FFF for right port, 0x1FFE for left port) to signal cross-port message arrival. Input Read Register (IRR) and Output Drive Register (ODR) extend functionality beyond basic memory access.

Key Specifications

Pinout & Package

Package: 100-ball, 0.5 mm pitch, 6 mm × 6 mm Pb-free BGA (ball layout per Figure 1, Rev. *K).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-port SRAM applications.

Compared with IS61WV12816BLL-10MLI and AS7C3128B-12TIN, CYDMX128B16-65BVXI trades raw speed for integrated system-level functions - including mailbox interrupts, port-independent I/O voltages, and configurable interface modes - reducing BOM count and firmware complexity in real-time embedded systems.

Availability

CYDMX128B16-65BVXI is available at Aetrix Electronics and suitable for industrial PLC backplane buffering, real-time motion controller memory, and embedded video frame buffering requiring stable component supply and long-term lifecycle support.

Supply support for CYDMX128B16-65BVXI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies is a global semiconductor leader headquartered in Munich, Germany, delivering power systems, sensors, microcontrollers, and memory solutions for industrial, automotive, and IoT applications.

CYDMX128B16 belongs to Infineon's MoBL® ADM dual-port SRAM product line, designed specifically for deterministic interprocessor communication in resource-constrained embedded systems requiring low power, mixed-voltage I/O, and hardware-accelerated messaging.

FAQ

What is the function of the MSEL pin on CYDMX128B16-65BVXI?

The MSEL pin configures the right port interface mode: logic LOW selects standard SRAM mode (addresses applied on dedicated A-bus), while logic HIGH selects ADM mode (addresses multiplexed on I/O bus). This setting is sampled at power-up and remains fixed until reset. It enables flexible integration with hosts having different addressing architectures without changing PCB layout.

How does the mailbox interrupt mechanism work in practice?

The mailbox uses the two highest memory addresses: 0x1FFF (right port mailbox) and 0x1FFE (left port mailbox). When one port writes to the opposite port's mailbox address, the corresponding INT# pin asserts LOW. The interrupt clears only when the owning port reads its own mailbox location. Power-up defaults both INT# pins HIGH, requiring initialization code to clear them before use.

Can CYDMX128B16-65BVXI operate with different supply voltages on left and right I/O ports?

Yes - VDDIOL and VDDIOR are independent power pins. Left port I/O can be powered at 1.8 V while right port I/O runs at 2.5 V or 3.0 V, supporting mixed-voltage system interfacing. Core VCC must be ≤ the lower of the two I/O voltages. This eliminates level-shifter components when connecting to heterogeneous processors or FPGAs.

What happens during a dual-port address collision, and how is it resolved?

When both ports assert CS# and access the same memory address simultaneously, on-chip arbitration asserts BUSY# on the losing port within 4.5 ns (tBLA). The winning port completes its access normally. The losing port's write is ignored and its read returns undefined data unless retried after BUSY# deasserts. No external logic is required - resolution is fully hardware-managed and deterministic in timing.