Renesas 7025S35J

Overview

IDT7025S35J from Integrated Device Technology (IDT) is a high-speed 8K × 16 (128 Kbit) true dual-port static RAM with independent asynchronous left/right ports, 35 ns maximum read cycle time, TTL-compatible 5 V ±10% supply, and industrial temperature range (–40°C to +85°C). It enables simultaneous read access to the same memory location and supports master/slave cascading for 32-bit+ bus expansion in real-time embedded control systems.

For engineers reviewing the IDT7025S35J datasheet, IDT7025S35J pinout, IDT7025S35J application, or IDT7025S35J equivalent, key selection considerations include BUSY-flag arbitration timing (tBAA ≤ 20 ns), semaphore-controlled inter-port signaling, byte-selectable I/O (UBL/LBL), and 84-pin PGA package compatibility with legacy military/industrial PCB layouts.

Technical Context

The IDT7025S35J implements fully asynchronous dual-port architecture with on-chip port arbitration logic and hardware semaphore support across eight flags addressed via A0–A2. Its dual independent control paths-separate CE/R/W/OE/UB/LB per port-enable concurrent read/write operations without external logic.

It features dedicated BUSY flag generation (M/S = H for master output; M/S = L for slave input), interrupt flag (INTL/INTR), and battery backup capability down to 2 V for data retention. The device uses CMOS process technology and supports TTL-level inputs with VIH ≥ 2.2 V and VIL ≤ 0.8 V at VCC = 5.0 V.

Key Specifications

Pinout & Package

Package: 84-pin Ceramic Pin Grid Array (PLG84), hermetically sealed, MIL-PRF-38535 QML-qualified, body size ≈ 1.15 in × 1.15 in × 0.17 in.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1370D-35AXC and AS7C38097A-35JC, the IDT7025S35J uniquely delivers integrated BUSY-flag arbitration and eight hardware semaphores in a 5 V, industrial-temperature 84-pin PGA package - making it irreplaceable in legacy military/industrial systems requiring deterministic contention resolution without added components.

Availability

IDT7025S35J is available at Aetrix Electronics and suitable for industrial motion controllers, avionics display buffers, and military radar signal processors requiring stable component supply across extended lifecycle programs.

Supply support for IDT7025S35J 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

Integrated Device Technology (IDT) was a fabless semiconductor company specializing in timing, memory interface, RF, and sensor solutions before its acquisition by Renesas Electronics in 2019. It pioneered high-performance dual-port memory architectures for real-time systems.

The IDT7025S35J belongs to IDT's legacy 7000-series dual-port SRAM family, engineered specifically for deterministic inter-processor communication in aerospace, defense, and industrial automation where hardware-enforced synchronization and MIL-spec packaging are mandatory.

FAQ

What is the maximum operating temperature range for the IDT7025S35J?

The IDT7025S35J is rated for industrial temperature operation from –40°C to +85°C. This range is validated per the datasheet's Recommended DC Operating Conditions table and applies to all speed grades including the 35 ns version. It does not support extended military ranges (–55°C to +125°C) unless explicitly ordered as a MIL-PRF-38535 QML-qualified variant.

Does the IDT7025S35J support battery backup operation, and what is the minimum retention voltage?

Yes, the IDT7025S35J supports battery backup operation with guaranteed data retention at VCC ≥ 2.0 V. The datasheet specifies VDR = 2.0 V (min) and characterizes ICCDR ≤ 4000 µA across all temperature ranges. This feature is intrinsic to the "L" suffix variants, and the IDT7025S35J - while an "S"-grade part - retains this capability per the family specification.

How does the BUSY flag function in master vs. slave configuration on the IDT7025S35J?

When M/S = H (high), the IDT7025S35J operates as a master: BUSYL is an output that asserts when port contention occurs, blocking writes on the slave side. When M/S = L (low), it operates as a slave: BUSYR becomes an input used to gate R/WR, enabling hardware-coordinated arbitration without software polling. This dual-role behavior is fixed per pin and defined in Truth Table I and Figure 13.

Can the IDT7025S35J be used in a 32-bit data bus system, and how is that implemented?

Yes, the IDT7025S35J supports 32-bit expansion via master/slave cascading. Two devices are connected with M/S = H on the master and M/S = L on the slave; BUSYL from master drives BUSYR on slave, and the master's INTL can be wired to the slave's INTR for synchronized interrupt signaling. This configuration requires no external logic and maintains full 35 ns timing across both 16-bit segments.

What are the key timing parameters governing semaphore operation on the IDT7025S35J?

Semaphore access on the IDT7025S35J is governed by tSOP (semaphore pulse width, min 10 ns), tSAA (semaphore address access, ≤35 ns max), and tSWRD (write-to-read delay, 5 ns min). Semaphores are accessed via A0–A2 with SEM = L, and require CE = VIH or UB&LB = VIH - distinct from RAM access timing. These parameters ensure atomic flag updates even during concurrent memory access.