Renesas 7133LA25J8

Overview

7133LA25J8 from IDT is a high-speed 2K × 16 dual-port static RAM with master arbitration logic, 25 ns maximum access time (industrial grade), 1.0 mA full-standby current, and battery backup data retention at 2 V. It supports independent asynchronous read/write on left and right ports and is used in real-time interprocessor communication systems requiring deterministic contention resolution.

For engineers reviewing the 7133LA25J8 datasheet, 7133LA25J8 pinout, 7133LA25J8 application, or 7133LA25J8 equivalent, this page delivers verified timing parameters, BUSY arbitration behavior, byte-select write control, industrial temperature operation (–40°C to +85°C), and package-specific pin mapping for PLCC-68.

Technical Context

The 7133LA25J8 implements on-chip port arbitration logic that resolves simultaneous accesses to identical memory addresses by asserting BUSYL or BUSYR as open-drain outputs - requiring external pull-up resistors. Its dual-port architecture permits fully asynchronous operation: address, control, and I/O lines are physically separated per port.

It supports separate upper- and lower-byte write enables (R/WLUB/R/WLLB and R/WRUB/R/WRLB), enabling partial-word writes without read-modify-write cycles. The LA variant achieves 1 mW standby power via CMOS optimization and retains data at V_CC = 2 V, making it suitable for battery-backed systems where low quiescent current is critical.

Key Specifications

Pinout & Package

7133LA25J8 is packaged in a 68-pin Plastic Leaded Chip Carrier (PLCC, code PLG68), with dual rows of leads and a body size of approximately 0.95 in × 0.95 in × 0.17 in. Both V_CC pins (pins 51 and 36) and both GND pins (pins 27 and 43) must be connected for reliable operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT7143LA25J8 and CY7C1335KV18-250BZC, the 7133LA25J8 uniquely integrates deterministic hardware arbitration and battery-retention capability in a 5 V, industrial-temperature dual-port SRAM - making it irreplaceable for safety-critical, low-power, real-time inter-CPU communication.

Availability

7133LA25J8 is available at Aetrix Electronics and suitable for real-time interprocessor communication, digital signal processing buffering, and redundant control system memory requiring stable component supply across extended product lifecycles.

Supply support for 7133LA25J8 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 timing, memory interface, RF, and sensor solutions, now part of Renesas Electronics.

The IDT7133/7143 family was designed specifically for deterministic, low-latency interprocessor communication in industrial, military, and telecom systems where hardware arbitration and battery backup are mandatory.

FAQ

What is the function of the BUSY pins on the 7133LA25J8?

The BUSYL and BUSYR pins on the 7133LA25J8 are open-drain outputs that signal port contention when both ports attempt access to the same memory address simultaneously. They require external pull-up resistors to V_CC. When asserted, BUSY stalls the contending port's write operation - a hardware-level arbitration mechanism unique to the MASTER 7133 variant. This behavior is documented in the functional description and timing waveforms of the official IDT datasheet for 7133LA25J8.

Does the 7133LA25J8 support true independent dual-port operation without arbitration overhead?

Yes - the 7133LA25J8 permits fully asynchronous, independent read/write operations on left and right ports as long as addresses do not collide. Arbitration logic activates only during same-address contention; otherwise, both ports operate at full 25 ns speed with no timing penalty. The device's separate address, control, and I/O pins ensure electrical and timing isolation - confirmed by AC timing tables and functional block diagrams in the 7133LA25J8 datasheet.

Can the 7133LA25J8 retain data at 2.0 V, and what is the typical current draw in that mode?

Yes - the 7133LA25J8 guarantees data retention at V_CC = 2.0 V, with typical data retention current (ICCDR) of 100 µA under industrial temperature conditions. This is explicitly specified in Table 8 of the datasheet. The LA suffix denotes low-power design optimized for battery backup; retention is maintained without refresh and is production-characterized - not just a theoretical limit.

Is the 7133LA25J8 pin-compatible with the IDT7143LA25J8?

Yes - the 7133LA25J8 and IDT7143LA25J8 share identical pinouts and package footprints (PLG68), including matching address, data, control, and power pin locations. However, BUSYL/BUSYR serve as outputs on the 7133LA25J8 but as inputs on the 7143LA25J8. This functional difference requires correct PCB routing: pull-ups on 7133LA25J8 BUSY lines, and connection to MASTER BUSY output when using 7143LA25J8 as SLAVE.

What is the minimum write pulse width required for reliable operation of the 7133LA25J8 at 25 ns speed?

The minimum write pulse width (tWP) for the 7133LA25J8 at 25 ns speed grade is 20 ns - specified in Table 11a of the datasheet under "WRITE CYCLE" parameters for 7133X25 variants. This applies to both byte-write enables (R/WLUB/R/WLLB and R/WRUB/R/WRLB). Pulse widths shorter than 20 ns risk incomplete write cycles or data corruption, especially under worst-case voltage and temperature conditions.