Renesas 7133LA55J

Overview

7133LA55J from IDT is a high-speed 2K × 16 dual-port static RAM with master arbitration logic, 55 ns max read cycle time, 5V single-supply operation, and 1 µA typical standby current - used in real-time inter-processor communication systems requiring concurrent access to shared memory without external arbitration logic.

For engineers reviewing the 7133LA55J datasheet, 7133LA55J pinout, 7133LA55J application, or 7133LA55J equivalent, this page delivers verified timing specs (tRC = 55 ns), byte-select write control, BUSY arbitration behavior, battery backup capability (2V data retention), and confirmed 68-pin PLCC package mapping - all validated against IDT's official 7133SA/LA datasheet revision Jun.16.21.

Technical Context

The 7133LA55J implements fully asynchronous dual-port architecture with independent left/right address, control, and I/O buses. It integrates on-chip port arbitration logic exclusive to the MASTER variant (IDT7133), generating open-drain BUSYL/BUSYR outputs that require pull-up resistors.

It supports separate upper/lower byte write enables (R/WLUB/R/WLLB and R/WRUB/R/WRLB) per port, TTL-compatible signaling, and automatic power-down via chip enable (CE). The LA suffix denotes low-power design enabling 2V battery backup with ≤4 mA data retention current.

Key Specifications

Pinout & Package

7133LA55J is packaged in a 68-pin Plastic Leaded Chip Carrier (PLCC, code PLG68), with dual-row gull-wing leads, 0.050″ pitch, and body dimensions ≈23.5 mm × 23.5 mm × 4.3 mm. Both VCC and GND pins must be connected for reliable operation (Notes 1–2, datasheet p.2).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 7133SA55J, the 7133LA55J reduces standby power by 80% and enables battery backup - critical for portable or fail-safe systems. Compared with 7143LA55J, it provides autonomous arbitration and standalone operation, eliminating dependency on external MASTER coordination logic.

Availability

7133LA55J is available at Aetrix Electronics and suitable for real-time inter-processor communication, digital signal processing buffering, and military avionics data hubs requiring stable component supply, long-term lifecycle support, and industrial temperature compliance.

Supply support for 7133LA55J 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, interface, and RF solutions - acquired by Renesas Electronics in 2019.

The IDT7133/7143 family was designed for deterministic, low-latency shared-memory architectures in embedded control, aerospace, and telecom infrastructure - prioritizing hardware arbitration, byte-select flexibility, and robust industrial/military operation.

FAQ

What does the 'LA' suffix mean in 7133LA55J?

The 'LA' suffix in 7133LA55J indicates the Low-Power version of the IDT7133 dual-port SRAM. It features 1 µA typical standby current (vs. 5 µA for SA), 2V data retention capability, and reduced active power consumption (1050 mW typ. vs. 1150 mW for SA). This makes 7133LA55J suitable for battery-backed or thermally sensitive applications where power efficiency is critical.

Is 7133LA55J pin-compatible with 7143LA55J?

Yes, 7133LA55J is pin-compatible with 7143LA55J per datasheet Section 2: "The IDT7133/7143 devices have identical pinouts." However, functional differences exist: 7133LA55J has on-chip arbitration logic and open-drain BUSY outputs, while 7143LA55J uses BUSY as inputs only and lacks arbitration - making them complementary, not interchangeable, in system design.

Does 7133LA55J support true simultaneous read/write operations?

Yes, 7133LA55J supports fully asynchronous, independent read and write operations on left and right ports - provided addresses do not collide. When both ports access the same memory location concurrently, on-chip arbitration asserts BUSYL/BUSYR to stall the later access. This ensures deterministic resolution without external logic, as confirmed in Functional Description (p.15) and Timing Waveform Figures 11–14.

What is the purpose of the two VCC and two GND pins on 7133LA55J?

The 7133LA55J has two VCC pins (17 and 51) and two GND pins (26 and 61) to reduce power delivery impedance and improve noise immunity across the 68-pin PLCC package. Datasheet Notes 1–2 explicitly require both VCC pins to be connected to the 5V supply and both GND pins to system ground - failure to do so risks timing violations, increased EMI susceptibility, or unreliable operation under load.

Can 7133LA55J operate with a 3.3V supply?

No, 7133LA55J is specified only for 5.0 V ±10% (4.5 V to 5.5 V) operation per DC Operating Conditions (Table 04). Its input thresholds (VIH = 2.2 V min., VIL = 0.8 V max.) and output drive levels are TTL-compatible, not LVTTL or LVCMOS. Using 3.3V violates absolute maximum ratings and will result in undefined behavior, including failed arbitration and data retention loss.