Renesas 7008L20JI

Overview

IDT7008L20JI from Integrated Device Technology (IDT) is a high-speed 64K × 8 true dual-ported static RAM with independent left/right ports, 20 ns maximum access time, TTL-compatible 5 V ±10% supply, and integrated BUSY arbitration logic. It enables simultaneous asynchronous reads from both ports to the same memory location and supports MASTER/SLAVE cascading for 16-bit+ data bus expansion in real-time embedded control systems.

For engineers reviewing the 7008L20JI datasheet, 7008L20JI pinout, 7008L20JI application, or 7008L20JI equivalent, key selection criteria include dual-port contention resolution timing (tBDD ≤ 20 ns), low standby power (1 mW typ.), industrial temperature range (–40°C to +85°C), and semaphore flag support for inter-processor synchronization.

Technical Context

The IDT7008L20JI implements fully asynchronous dual-port operation with separate address, control, and I/O buses per port. Its on-chip arbitration logic uses push-pull BUSY outputs (not tri-state) and supports both address-match and CE-controlled BUSY assertion modes with tAPS = 5 ns priority setup time.

It integrates full hardware semaphore signaling across eight flags addressed by A0–A2, accessed via dedicated SEM enable with CE = VIH, and supports interrupt flag generation at fixed addresses FFFE_H (INTL) and FFFF_H (INTR), where write-to-clear or read-to-clear behavior is defined per port.

Key Specifications

Pinout & Package

7008L20JI is packaged in an 84-pin Ceramic Pin Grid Array (PGA) with 1.15 in × 1.15 in body size. All V_CC and GND pins must be connected per datasheet Note 1 and Note 4.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-20JC and AS7C3616A-20JIN, the 7008L20JI delivers self-contained dual-port arbitration, reducing BOM count by one IC and eliminating timing-critical external glue logic-critical for safety-critical and space-constrained designs.

Availability

7008L20JI is available at Aetrix Electronics and suitable for real-time motion control, avionics display management, and redundant safety PLC applications requiring stable component supply, long-lifecycle support, and industrial temperature qualification.

Supply support for 7008L20JI 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.

The IDT7008 product line was designed specifically for deterministic inter-processor communication in hard real-time embedded systems, emphasizing hardware-accelerated arbitration, low-latency interrupt signaling, and seamless bus-width scalability.

FAQ

What is the operating temperature range specified for the 7008L20JI?

The 7008L20JI is rated for industrial temperature operation from –40°C to +85°C, with all AC and DC electrical specifications guaranteed across this full range under 5.0 V ±10% supply conditions. This qualification enables deployment in harsh environments such as factory automation controllers and outdoor telecom infrastructure where ambient thermal cycling exceeds commercial grade limits.

How does the BUSY arbitration logic function in the 7008L20JI when configured as a Master?

When M/S = VIH, the 7008L20JI operates as a Master and drives BUSYL and BUSYR as push-pull outputs. BUSY asserts when address or chip enable contention occurs between ports, with tBDD ≤ 20 ns defining the delay from BUSY deassertion to valid read data. This hardware arbitration eliminates software polling and guarantees deterministic resolution without external logic.

Can the 7008L20JI support semaphore operations without external components?

Yes, the 7008L20JI includes full on-chip hardware support for eight semaphore flags addressed by A0–A2. Access requires CE = VIH and SEM = VIL, and writes occur via I/O0 while reads return the flag value on all I/O lines (I/O0–I/O7). No external latches, logic, or firmware coordination is needed for basic token-passing protocols.

What is the standby current consumption of the 7008L20JI in full-power-down mode?

In full standby mode (ISB3), where both ports have CMOS-level inputs (CE > V_CC – 0.2 V, all inputs at rail), the 7008L20JI consumes 0.2 mA typical current. This ultra-low quiescent draw enables use in battery-backed systems and energy-sensitive industrial nodes where continuous memory retention is required with minimal leakage.

Does the 7008L20JI require external termination or biasing for reliable operation?

No external termination is required for standard operation. The 7008L20JI uses TTL-compatible input thresholds (V_IL ≤ 0.8 V, V_IH ≥ 2.2 V) and push-pull outputs capable of driving 4 mA loads. Per datasheet Note 2, V_TERM must not exceed V_CC + 10% for more than 10 ns or 25% duty cycle, but no external resistors or bias networks are mandated for compliant 5 V systems.