Renesas 7009L20PFG

Overview

7009L20PFG from IDT is a high-speed 128K × 8 true dual-ported static RAM with independent left/right ports, 20 ns max access time (industrial/commercial), TTL-compatible 5 V ±10% supply, and integrated hardware semaphore/INT/BUSY arbitration logic. It enables simultaneous asynchronous reads of the same memory location and supports master/slave cascading for 16-bit+ bus expansion in real-time embedded control systems.

For engineers reviewing the 7009L20PFG datasheet, 7009L20PFG pinout, 7009L20PFG application, or 7009L20PFG equivalent, key selection considerations include dual-port contention handling via BUSY flag timing (tBDD ≤ 17 ns), semaphore write-to-read latency (tSWRD = 5 ns), interrupt mailbox addressing (1FFFE/1FFFF hex), and 100-pin TQFP package compatibility with industrial temperature range (–40°C to +85°C).

Technical Context

The 7009L20PFG implements fully asynchronous dual-port operation with separate CE0/CE1, R/W, OE, and address buses per port. Its on-chip arbitration logic resolves port-to-port conflicts using push-pull BUSY outputs (not open-drain) and supports both master (BUSY output) and slave (BUSY input) modes via the M/S pin.

Hardware semaphore functionality uses eight dedicated latches addressed by A0–A2, accessible only when CE = VIH and SEM = VIL, with write-to-read propagation delay tSWRD = 5 ns. Interrupt flags (INTL/INTR) are set/cleared by writes/reads to fixed SRAM addresses (1FFFE/1FFFF), requiring no external logic for interprocessor messaging.

Key Specifications

Pinout & Package

7009L20PFG is housed in a 100-pin Thin Quad Flatpack (TQFP) with 14 mm × 14 mm body and 1.4 mm height. All GND pins must be connected to ground; all VCC pins require decoupling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1370D-200BAXI and AS7C3128P-20JCIN, the 7009L20PFG uniquely integrates hardware semaphore, interrupt mailbox, and BUSY arbitration in a 5 V, 100-pin TQFP package-enabling deterministic sub-20 ns interprocessor communication without external logic or voltage translation.

Availability

7009L20PFG is available at Aetrix Electronics and suitable for real-time industrial PLCs, avionics data exchange modules, medical imaging pipelines, test equipment pattern memory, and deterministic multi-processor embedded systems requiring stable component supply across extended lifecycles.

Supply support for 7009L20PFG 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 high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The 7009L20PFG belongs to IDT's legacy dual-port SRAM product line, designed specifically for deterministic interprocessor communication in real-time embedded systems requiring hardware-enforced resource arbitration and zero-software-overhead messaging.

FAQ

What is the maximum operating temperature range supported by the 7009L20PFG?

The 7009L20PFG is rated for industrial temperature operation from –40°C to +85°C, as confirmed in the Absolute Maximum Ratings and Recommended DC Operating Conditions tables. This range applies to both commercial and industrial speed grades of the 7009L20PFG, making it suitable for harsh-environment embedded applications without derating.

How does the BUSY arbitration logic function in master versus slave mode on the 7009L20PFG?

In master mode (M/S = VIH), the 7009L20PFG drives BUSYL/BUSYR as push-pull outputs to signal port contention; in slave mode (M/S = VIL), BUSYL/BUSYR become inputs that internally inhibit writes when asserted low. The 7009L20PFG's BUSY outputs require no pull-up resistors due to their totem-pole structure, unlike open-drain alternatives.

Can the 7009L20PFG support simultaneous read operations from both ports to the same memory address?

Yes, the 7009L20PFG's true dual-port architecture allows simultaneous reads from identical addresses on the left and right ports without conflict, timing penalty, or data corruption. This capability is explicitly stated in the Features section and enabled by its dedicated memory cell design-no BUSY assertion or arbitration occurs during concurrent reads.

What are the exact memory addresses used for interrupt flag control in the 7009L20PFG?

Interrupt flags in the 7009L20PFG are controlled via two fixed SRAM addresses: writing to 1FFFEh (hex) sets the left-port INTL flag, and reading from 1FFFEh clears it; writing to 1FFFFh (hex) sets the right-port INTR flag, and reading from 1FFFFh clears it. These locations are part of the main 128K × 8 array and retain user-defined 8-bit payloads.

Does the 7009L20PFG require external pull-up resistors on its BUSY or interrupt pins?

No, the 7009L20PFG's BUSYL, BUSYR, INTL, and INTR pins are configured as non-tri-state totem-pole (push-pull) outputs, as explicitly noted in the Functional Block Diagram notes. This eliminates the need for external pull-up resistors and ensures clean, rail-to-rail signaling compatible with standard TTL inputs.