Renesas 7140LA100P

Overview

7140LA100P from IDT (Integrated Device Technology) is a 1K × 8 dual-port static RAM configured as a SLAVE device in MASTER/SLAVE memory expansion systems, supporting fully asynchronous left/right port access with 100ns max read/write cycle time, 1μA full-standby current (CMOS-level CE), and 2V battery-backed data retention - deployed in real-time industrial controllers requiring concurrent host/DSP memory access.

For engineers reviewing the 7140LA100P datasheet, 7140LA100P pinout, 7140LA100P application, or 7140LA100P equivalent, key selection criteria include BUSY input timing (tWB = 0ns), slave-side arbitration behavior, dual 5V ±10% port independence, and compatibility with IDT7130 MASTER devices in 16-bit+ bus architectures.

Technical Context

The 7140LA100P implements a true dual-port SRAM architecture with physically separate left (L) and right (R) address/data/control buses, enabling simultaneous non-blocking reads/writes when accessing different memory locations. Its BUSY pins (BUSYL/BUSYR) are inputs only - unlike the MASTER IDT7130 - and internally inhibit writes upon assertion, eliminating external arbitration logic.

It supports R/W-controlled and CE-controlled write cycles, with tWP = 55ns (min), tWC = 100ns (max), and port-to-port timing parameters including tWDD = 120ns (max) and tDDD = 100ns (max). The LA variant enables data retention at VCC = 2.0V with ICCDR ≤ 4000µA (military grade) and ≤ 1500µA (commercial grade).

Key Specifications

Pinout & Package

48-pin plastic DIP (PDG48) package, 0.600-inch width, through-hole mount, RoHS-compliant lead finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1352BV18-100AXC and IDT7130LA100P, the 7140LA100P uniquely delivers hardware-enforced SLAVE arbitration, 2V data retention, and drop-in compatibility with legacy 5V industrial buses - making it irreplaceable for maintaining existing MASTER/SLAVE memory systems.

Availability

7140LA100P is available at Aetrix Electronics and suitable for motor control interfaces, DSP co-processor buffers, redundant PLC memory systems requiring stable component supply across extended production lifecycles.

Supply support for 7140LA100P 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 high-performance silicon solutions, now part of Renesas Electronics.

The IDT7130/7140 family was designed specifically for deterministic, low-latency dual-processor memory sharing in industrial automation, avionics, and test equipment - prioritizing hardware arbitration over software-managed coherency.

FAQ

What is the role of BUSYL and BUSYR on the 7140LA100P?

On the 7140LA100P, BUSYL and BUSYR are dedicated input-only signals - unlike the MASTER IDT7130 - that must be driven LOW by an external MASTER device (e.g., IDT7130LA100P) to inhibit writes to the corresponding port. They are not internally generated and require external pull-up resistors to VIH when inactive. This design enforces hardware-level write blocking during memory contention without software intervention.

Does the 7140LA100P support battery backup operation?

Yes, the 7140LA100P supports battery backup operation with guaranteed data retention down to VCC = 2.0V. In data retention mode, ICCDR is ≤1500µA (commercial grade) or ≤4000µA (military grade) at TA = +25°C. The LA suffix explicitly denotes this low-power retention capability - the SA variant does not support 2V operation.

Can the 7140LA100P be used as a standalone dual-port RAM without a MASTER device?

No - the 7140LA100P is functionally a SLAVE device: it lacks on-chip arbitration logic and BUSY output capability. It requires an external MASTER (e.g., IDT7130) to drive its BUSYL/BUSYR inputs and manage port contention. Using it standalone risks undetected write collisions and data corruption; the datasheet explicitly defines it for MASTER/SLAVE pairing only.

What is the meaning of "100" in the part number 7140LA100P?

The "100" in 7140LA100P specifies the maximum access speed grade: 100ns read cycle time (tRC). This corresponds to the slowest speed bin in the LA family (other variants include 20, 25, 35, 55, and 100ns). All electrical timing parameters - including tAA, tACE, tWP - are guaranteed to meet or exceed the 100ns specification across the industrial temperature range.

Which package type does the 7140LA100P use, and is it RoHS-compliant?

The 7140LA100P uses a 48-pin plastic DIP (PDG48) package with 0.600-inch width and standard through-hole footprint. Per IDT documentation, PDG48 variants are RoHS-compliant (lead-free terminations) and halogen-free, meeting JEDEC J-STD-609A Class 1 moisture sensitivity and IPC/JEDEC J-STD-020D reflow profiles.