Renesas 7024S15JI

Overview

7024S15JI from IDT is a high-speed 4K × 16 true dual-port static RAM with independent left/right ports, 15 ns max read cycle time (commercial grade), TTL-compatible 5V ±10% supply, and on-chip semaphore arbitration logic. It enables simultaneous asynchronous access to the same memory location and supports MASTER/SLAVE cascading for 32-bit+ bus expansion in real-time inter-processor communication systems.

For engineers reviewing the 7024S15JI datasheet, 7024S15JI pinout, 7024S15JI application, or 7024S15JI equivalent, key selection criteria include dual-port arbitration timing (tAPS = 5 ns), BUSY flag propagation (tBDD ≤ 30 ns), battery-backed data retention at 2V (IDT7024L variant), and compatibility with 84-pin PLCC/PGA/Flatpack packages.

Technical Context

The 7024S15JI implements fully asynchronous dual-port operation with separate address, control, and I/O buses per port - enabling concurrent read/write without external logic. Its on-chip arbitration logic resolves port contention via BUSY flag signaling and supports semaphore flag management across eight shared flags addressed by A0–A2.

It features separate upper-byte (UB/UBR) and lower-byte (LB/LBR) enables for multiplexed bus compatibility, full TTL-level interfacing, and automatic power-down via chip enable (CE). The device operates across industrial temperature (–40°C to +85°C) and uses CMOS high-performance fabrication for 750 mW typical active power.

Key Specifications

Pinout & Package

7024S15JI is packaged in an 84-pin Plastic Leaded Chip Carrier (PLCC), with all VCC and GND pins requiring direct connection to power/ground planes. Pin functions are strictly port-dual: left port (L) and right port (R) each have dedicated address (A0L–A11L / A0R–A11R), data (I/O0L–I/O15L / I/O0R–I/O15R), and control (CEL/CER, R/WL/R/WR, OEL/OER, UBL/UBR, LBL/LBR) signals.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C024AV-15AXC and IDT70V24S15PF, the 7024S15JI provides native 5V TTL operation, hardware semaphore support, and drop-in compatibility with existing 84-pin PLCC layouts-making it optimal for industrial retrofits and avionics upgrades where voltage and footprint constraints dominate.

Availability

7024S15JI is available at Aetrix Electronics and suitable for real-time inter-processor communication, digital signal processing buffering, and avionics data concentrator applications requiring stable component supply across extended product lifecycles.

Supply support for 7024S15JI 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, and RF solutions, now part of Renesas Electronics since 2019.

The IDT7024 family was designed for deterministic, low-latency shared memory in dual-processor and real-time control systems-emphasizing hardware arbitration, semaphore support, and industrial-grade reliability.

FAQ

What is the maximum operating frequency supported by the 7024S15JI?

The 7024S15JI has a maximum read cycle time of 15 ns, corresponding to a theoretical maximum sustained access rate of 66.7 MHz. This is a guaranteed timing specification under commercial temperature conditions (0°C to +70°C) and does not represent clock frequency but rather the minimum interval between consecutive read operations on the same port. The 7024S15JI does not use a system clock; all timing is asynchronous and governed by control signal setup/hold relationships.

Does the 7024S15JI support battery backup for data retention?

The 7024S15JI itself is the standard-power "S" variant and does not guarantee data retention below 4.5 V. However, it belongs to the IDT7024S/L family, where the "L" version (e.g., 7024L15JI) supports 2 V data retention with typical standby current of 1 µA. For battery backup operation, the L-version must be selected; the S-version remains fully pin- and function-compatible but lacks the low-voltage retention spec.

How does the MASTER/SLAVE configuration work on the 7024S15JI?

When M/S = HIGH, the 7024S15JI operates as a MASTER: BUSYL and BUSYR become outputs that assert during port contention. When M/S = LOW, it operates as a SLAVE: BUSYL and BUSYR become inputs that must be driven by a MASTER device's BUSY outputs. This enables daisy-chained arbitration in multi-device 32-bit+ systems without external logic, with the MASTER resolving priority and signaling contention status to SLAVES.

Can both ports of the 7024S15JI perform simultaneous reads to the same memory address?

Yes-the 7024S15JI uses true dual-ported memory cells that allow completely independent, simultaneous reads from the same address location on the left and right ports. No arbitration delay, BUSY assertion, or timing penalty occurs in this mode. This capability is fundamental to its architecture and is explicitly confirmed in the datasheet's "True Dual-Ported memory cells" feature statement.

What package type is used for the 7024S15JI, and is it RoHS-compliant?

The 7024S15JI is supplied in an 84-pin Plastic Leaded Chip Carrier (PLCC) package, as indicated by the "J" suffix in the part number per IDT's ordering guide. It is a green (RoHS-compliant) part, consistent with IDT's "Green parts available" notice in the datasheet and compliant with lead-free reflow profiles. The PLCC body measures approximately 1.15 in × 1.15 in × 0.17 in.