Renesas 70V26L55J8

Overview

70V26L55J8 from Integrated Device Technology is a high-speed 3.3V 16K × 16 (256 Kbit) true dual-port static RAM with independent left/right ports, 55 ns max access time, 660 µW typical standby power, and on-chip semaphore logic for inter-processor resource arbitration in real-time embedded control systems.

For engineers reviewing the 70V26L55J8 datasheet, 70V26L55J8 pinout, 70V26L55J8 application, or 70V26L55J8 equivalent, this page delivers verified specifications, validated package mapping to 84-pin PLCC, confirmed dual-port arbitration behavior, and two production-validated alternative parts for system-level memory expansion and master/slave configuration.

Technical Context

The 70V26L55J8 implements fully asynchronous dual-port operation with separate address, data, and control buses per port-enabling simultaneous read/write to any memory location without internal contention. Its hardware-based BUSY arbitration logic resolves port-to-port address conflicts via push-pull BUSYL/BUSYR outputs when M/S = VIH (master mode), or accepts BUSY as write-inhibit inputs when M/S = VIL (slave mode).

On-chip semaphore logic provides eight independent latches accessible via dedicated SEM control (CE = VIH, SEM = VIL), addressed by A0–A2, and readable/writable through I/O0–I/O15. Semaphore state is active-low; token acquisition requires writing '0', release requires writing '1'-all without CPU wait states or software polling overhead.

Key Specifications

Pinout & Package

70V26L55J8 is packaged in an 84-pin Plastic Leaded Chip Carrier (PLCC), body size ≈ 1.15 in × 1.15 in × 0.17 in, with all VDD pins requiring connection to 3.3V supply and all VSS pins tied to ground.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C026V-55AXC and IDT70V27L55PF, the 70V26L55J8 uniquely combines 84-pin PLCC packaging, push-pull BUSY outputs eliminating external pull-ups, and fully integrated semaphore logic - reducing BOM count and board area in space-constrained industrial controllers.

Availability

70V26L55J8 is available at Aetrix Electronics and suitable for industrial motion control, dual-processor DSP systems, and programmable logic controller (PLC) applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for 70V26L55J8 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), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, RF, and sensor signal conditioning ICs for high-performance computing and industrial applications.

The 70V26L55J8 belongs to IDT's high-speed dual-port SRAM product line, designed specifically for real-time embedded systems requiring deterministic memory access, hardware-based inter-processor coordination, and low-power standby operation.

FAQ

What is the maximum operating temperature range for the 70V26L55J8?

The 70V26L55J8 is rated for industrial temperature operation from –40°C to +85°C. This specification is validated across all electrical parameters including 55 ns access time, 660 µW standby current, and BUSY arbitration timing (tBAA ≤ 45 ns). The device meets this range under continuous bias with VDD = 3.3 V ± 0.3 V and complies with IDT's industrial qualification standards.

Does the 70V26L55J8 support true simultaneous read operations from both ports to the same memory address?

Yes, the 70V26L55J8 supports true simultaneous reads from both ports to the same memory location without data corruption or timing penalty. This behavior is guaranteed by its true dual-port SRAM cell architecture and is explicitly documented in the Functional Block Diagram and Truth Table I. No BUSY assertion occurs during concurrent reads, and tAA remains 55 ns for both ports independently.

How does the semaphore logic in the 70V26L55J8 differ from standard memory-mapped I/O implementations?

The 70V26L55J8 semaphore logic consists of eight dedicated, hardware-latched registers decoupled from the main RAM array. Access requires CE = VIH and SEM = VIL - placing it in a separate address space selected by A0–A2. Unlike software-managed semaphores, this implementation guarantees atomic set/test operations with tSOP ≤ 15 ns and eliminates CPU polling, making it ideal for hard real-time coordination between autonomous processors.

Can the 70V26L55J8 be used in a master/slave configuration for 32-bit data bus expansion?

Yes, the 70V26L55J8 supports master/slave cascading via the M/S pin. When configured as master (M/S = VIH), BUSYL/BUSYR drive push-pull outputs; as slave (M/S = VIL), they accept BUSY as write-inhibit inputs. Two devices can be combined for 32-bit word width with one master arbitrating BUSY across both, enabling full-speed error-free operation without external logic - as confirmed in the IDT70V26 datasheet Section 2.

What is the power consumption difference between active and standby modes for the 70V26L55J8?

In active mode (both ports enabled, f = fMAX), the 70V26L55J8 draws 90 mA typical (ICC = 90 mA), equating to ~300 mW at 3.3 V. In full standby (CE and SEM high, CMOS-level inputs), it consumes only 0.2 mA typical (ISB3 = 0.2 mA), or 660 µW - a 450× reduction. This low-ISB3 value is specific to the 'L' (low-power) variant and is measured with VIN > VDD − 0.2 V or VIN < 0.2 V.