Renesas 7133LA55G

Overview

7133LA55G from IDT is a high-speed 2K × 16 dual-port static RAM with master arbitration logic, 55 ns max read cycle time, 2.0 V data retention capability, and 1 mW typical standby power. It supports fully asynchronous dual-port access with separate byte-write controls per port and operates across industrial temperature range (–40°C to +85°C) on single 5V ±10% supply - used in real-time DSP co-processing, military avionics bus buffering, and redundant controller memory subsystems.

For engineers reviewing the 7133LA55G datasheet, 7133LA55G pinout, 7133LA55G application, or 7133LA55G equivalent, this page delivers verified timing parameters, BUSY arbitration behavior, byte-select write control implementation, industrial-grade reliability specs, and direct alternatives for width-expansion systems requiring deterministic contention resolution.

Technical Context

The 7133LA55G implements on-chip port arbitration logic exclusively in MASTER mode, generating open-drain BUSY output signals (BUSYL/BUSYR) that require external pull-up resistors. Its dual independent ports support simultaneous read/write operations with no internal synchronization overhead.

It enables 32-bit+ data bus expansion via MASTER/SLAVE configuration with IDT7143LA55G, where only the MASTER asserts BUSY and SLAVES accept it as a write-inhibit input - eliminating "busy lock-out" through centralized arbitration and eliminating need for external logic.

Key Specifications

Pinout & Package

7133LA55G is packaged in a 68-pin PLCC (PLG68) with 0.95″ × 0.95″ footprint. Both VCC pins must be connected to 5V and both GND pins to ground for reliable operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7143LA55G and CY7C1335KV18-55BGXI, the 7133LA55G uniquely integrates deterministic hardware arbitration and 2V data retention - making it the only option for standalone, fault-resilient dual-CPU memory sharing without external components.

Availability

7133LA55G is available at Aetrix Electronics and suitable for real-time DSP co-processing, military avionics bus interface, and redundant controller memory subsystems requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for 7133LA55G 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

IDT (Integrated Device Technology) is a fabless semiconductor company specializing in high-performance memory, timing, and interface solutions for communications, computing, and industrial markets.

The 7133LA55G belongs to IDT's legacy dual-port SRAM product line, designed specifically for deterministic real-time systems requiring hardware-managed memory contention resolution and battery-backed data integrity.

FAQ

What is the function of the BUSY pins on the 7133LA55G?

The BUSYL and BUSYR pins on the 7133LA55G are open-drain outputs that signal address contention between ports. When both ports attempt access to the same memory location, the on-chip arbitration logic asserts BUSY to stall the lower-priority port. Because they are open-drain, each requires an external pull-up resistor to VCC. This mechanism ensures deterministic resolution without software intervention - a core feature distinguishing the 7133LA55G from SLAVE-only variants like IDT7143LA55G.

Does the 7133LA55G support true simultaneous read/write operations?

Yes, the 7133LA55G supports fully asynchronous, simultaneous read and write operations on its left and right ports - provided the accessed addresses differ. If addresses match, the built-in arbitration logic uses BUSY signaling to prevent corruption. The device does not require clock synchronization between ports, and timing parameters like tRC (55 ns) and tWC (55 ns) are specified independently per port - enabling true concurrent access in applications such as dual-CPU shared memory or FPGA-processor bridging.

How does the 2V data retention capability of the 7133LA55G work in practice?

The 7133LA55G maintains valid data at VCC = 2.0 V with typical ICCDR of 100 µA - enabling battery backup operation during main power failure. In practice, this means connecting a 2–3 V lithium cell to VCC while disabling CE on both ports. The device enters data retention mode automatically when CE is high and VCC drops below 4.5 V. No external circuitry is needed beyond the battery and isolation diode; the 7133LA55G continues holding all 32,768 bits without refresh - a key requirement for avionics and industrial safety systems.

Can the 7133LA55G be used without the BUSY arbitration feature?

Yes, the 7133LA55G can operate without utilizing BUSY arbitration by ensuring non-overlapping address access patterns between ports - for example, dedicating fixed memory regions to each port. In such configurations, BUSYL and BUSYR may be left unconnected or tied high via pull-ups. However, disabling arbitration forfeits the device's primary differentiator: hardware-enforced contention resolution. For systems where deterministic timing and fault resilience are critical, leveraging BUSY remains essential - and the 7133LA55G is the only variant in the family offering this logic natively.

What package options are available for the 7133LA55G, and which is most commonly stocked?

The 7133LA55G is manufactured in 68-pin PLCC (PLG68), 68-pin ceramic PGA (GU68), 68-pin flatpack (FP68), and 100-pin TQFP (PNG100). Of these, the 68-pin PLCC is the most widely available and commonly stocked variant due to its robustness, ease of inspection, and compatibility with standard industrial PCB assembly processes. All packages share identical pinouts and electrical specifications - allowing direct substitution based on mechanical or thermal constraints without redesign.