Infineon Technologies CYDM128B16-55BVXIT

Overview

CYDM128B16-55BVXIT from Cypress Semiconductor is a 8K × 16 (128 Kbit), 1.8 V asynchronous dual-port static RAM with true dual-port architecture, 55 ns maximum access time, on-chip arbitration logic, and independent 1.8 V I/O voltage support per port. It enables simultaneous read/write access to the same memory location in interprocessor communication systems requiring deterministic data coherency.

For engineers reviewing the CYDM128B16-55BVXIT datasheet, CYDM128B16-55BVXIT pinout, CYDM128B16-55BVXIT application, or CYDM128B16-55BVXIT equivalent, key selection factors include port-independent I/O voltage tolerance (1.8/2.5/3.0 V), integrated semaphores for software handshaking, master/slave expandability to 32-bit bus width, and ultra-low standby current of 2 µA at 1.8 V.

Technical Context

This device implements fully asynchronous dual-port SRAM architecture with separate address, data, and control buses for left and right ports. Each port features independent Chip Enable (CE), Read/Write (R/W), Output Enable (OE), BUSY, and INT signals, enabling concurrent access without external arbitration logic.

On-chip arbitration resolves contention via hardware-based priority resolution with tPS setup timing, while eight shared semaphore latches provide software-controlled resource locking. The M/S pin configures the device as master (BUSY output) or slave (BUSY input), supporting seamless 32-bit expansion without discrete logic.

Key Specifications

Pinout & Package

Package: 100-ball, 0.5 mm pitch, 6 × 6 mm Pb-free vfBGA (ball grid array). Thermal and mechanical characteristics conform to JEDEC MO-277.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT70V27L15PF8 and IS61WV12816BLL-10TLI, CYDM128B16-55BVXIT uniquely delivers 1.8 V dual-port operation with integrated arbitration and expandable bus width in a compact 6 × 6 mm BGA - essential for space- and power-constrained multi-processor edge nodes.

Availability

CYDM128B16-55BVXIT is available at Aetrix Electronics and suitable for interprocessor communication, dual-port video buffering, and redundant control system memory requiring stable component supply across industrial temperature ranges and long product lifecycles.

Supply support for CYDM128B16-55BVXIT 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

Cypress Semiconductor (now part of Infineon Technologies) designs high-performance, low-power memory and programmable solutions for embedded systems, automotive, and industrial applications.

CYDM128B16 belongs to the MoBL® (Mobile Low-Power) Dual-Port SRAM product line, engineered specifically for deterministic, low-latency interprocessor communication in space-constrained, power-sensitive embedded systems.

FAQ

What is the function of the M/S pin on CYDM128B16-55BVXIT?

The M/S pin configures the device as master (M/S = HIGH) or slave (M/S = LOW). In master mode, BUSYR functions as an output signaling arbitration outcome to a connected slave device. In slave mode, BUSYL serves as an input accepting BUSY from the master, enabling synchronized 32-bit bus expansion without external logic. This pin eliminates the need for separate master and slave part numbers.

How does the semaphore feature work in practice?

The CYDM128B16-55BVXIT provides eight shared semaphore latches accessible via SEM enable. One port asserts SEM and writes a value to trigger a token; the other port reads the latch to confirm resource availability. Only one port can control a given semaphore at a time, preventing race conditions. This enables lock-free software handshaking for shared peripherals like ADCs or UARTs without CPU polling.

Can both ports operate at different I/O voltages simultaneously?

Yes. VDDIOL and VDDIOR are electrically isolated power pins supporting independent 1.8 V, 2.5 V, or 3.0 V I/O standards. For example, the left port may interface with a 1.8 V FPGA core while the right port connects to a 3.0 V microcontroller's data bus - no external level shifters required. Core VCC must be ≤ the lower of the two I/O voltages.

What happens during simultaneous access to the same memory location?

On-chip arbitration logic detects address matches within tPS (setup time) and grants access to one port while asserting BUSY on the contending port. The winning port completes its cycle; the losing port waits until BUSY deasserts before retrying. This hardware resolution avoids software intervention and guarantees deterministic behavior - critical for real-time interprocessor messaging where deadlock must be prevented.