Renesas 7028L20PFGI8

Overview

7028L20PFGI8 from IDT (now Renesas) is a high-speed 64K × 16 true dual-ported static RAM with independent left/right ports, 20 ns max access time (industrial grade), TTL-compatible 5V ±10% supply, and integrated hardware semaphore/arbiter logic for inter-processor synchronization in real-time embedded systems.

For engineers reviewing the 7028L20PFGI8 datasheet, 7028L20PFGI8 pinout, 7028L20PFGI8 application, or 7028L20PFGI8 equivalent, this page delivers verified timing specs (tAA = 20 ns, tRC = 20 ns), BUSY/INT arbitration behavior, dual-port I/O byte control (UBL/LBR, UBL/LBL), M/S master/slave configuration, and industrial temperature support (–40°C to +85°C).

Technical Context

The 7028L20PFGI8 implements fully asynchronous dual-port operation with separate address buses (A0L–A15L / A0R–A15R), independent chip enables (CE0L/CE1L and CE0R/CE1R), and dedicated semaphore registers accessed via SEM = VIL and A0–A2. Its on-chip arbitration logic asserts BUSYL/BUSYR outputs when address contention occurs, enabling hardware stall coordination between processors.

It supports simultaneous read/write to the same memory location only in true dual-port mode (M/S = VIH); in slave mode (M/S = VIL), BUSY pins become inputs that inhibit writes. Semaphore flags (8 total) are latched via I/O0 and readable across all 16 I/O lines, with tSAA = 20 ns and tSPS = 5 ns contention window - critical for deterministic token-passing protocols.

Key Specifications

Pinout & Package

7028L20PFGI8 is housed in a 100-pin Thin Quad Flatpack (TQFP) with exposed thermal pad (PNG100 package code). Pin 1 is located at top-left corner (marking dot adjacent to pin 1), and all VCC (pins 26, 50, 75, 99) and GND (pins 1, 25, 51, 74, 100) must be decoupled per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1370D-200BZI and IS61WV102416BLL-10TLI, the 7028L20PFGI8 uniquely integrates hardware semaphore, BUSY arbitration, and 5V TTL compatibility - making it irreplaceable in legacy industrial and avionics designs requiring deterministic, zero-software-overhead inter-processor communication.

Availability

7028L20PFGI8 is available at Aetrix Electronics and suitable for industrial PLC communication hubs, avionics data concentrators, and medical imaging frame buffers requiring stable component supply across extended product lifecycles.

Supply support for 7028L20PFGI8 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), now part of Renesas Electronics, specializes in high-performance timing, memory, and interface solutions for mission-critical infrastructure.

The 7028L20PFGI8 belongs to IDT's legacy dual-port SRAM family, engineered specifically for deterministic inter-processor communication in real-time embedded systems where hardware arbitration and semaphore logic eliminate software-induced jitter.

FAQ

What is the maximum operating temperature range for the 7028L20PFGI8?

The 7028L20PFGI8 is rated for industrial temperature operation from –40°C to +85°C, as confirmed in the datasheet's "Recommended DC Operating Conditions" table (4836 tbl 03). This specification applies to the 7028L20PFGI8 variant specifically and supports deployment in harsh environments such as factory automation controllers and outdoor telecom equipment.

Does the 7028L20PFGI8 support true simultaneous read operations from both ports to the same memory address?

Yes, the 7028L20PFGI8 implements true dual-port memory cells that allow concurrent reads from the same location on both left and right ports without contention or delay - a core feature explicitly stated in the "Features" section and validated in the functional description. This capability is intrinsic to the 7028L20PFGI8 silicon design and does not require BUSY or semaphore activation.

How does the M/S pin affect BUSY pin functionality on the 7028L20PFGI8?

When M/S = VIH, BUSYL and BUSYR operate as push-pull outputs indicating address contention; when M/S = VIL, they become inputs that internally inhibit writes on the respective port. This dual-mode behavior is defined in Note 1 of the Functional Block Diagram and confirmed in the "Busy Logic" section - a defining characteristic of the 7028L20PFGI8's arbitration architecture.

What are the timing requirements for reliable semaphore flag access on the 7028L20PFGI8?

For semaphore access, the 7028L20PFGI8 requires SEM = VIL, CE = VIH, and tSAA ≤ 20 ns (address setup) and tSPS ≥ 5 ns (contention window) as specified in AC Electrical Characteristics Table 14. These values are guaranteed for the 7028L20PFGI8 variant and ensure deterministic flag acquisition in token-passing protocols without software retries.

Can the 7028L20PFGI8 be used in a 32-bit data bus configuration?

Yes, the 7028L20PFGI8 supports 32-bit expansion via Master/Slave cascading: one device operates as master (M/S = VIH) and another as slave (M/S = VIL), using BUSY signals to coordinate access. This topology is explicitly documented in the device description and enables full-speed 32-bit word systems without external logic - a key capability of the 7028L20PFGI8.