Renesas 7028L15PF8

Overview

7028L15PF8 from IDT (Integrated Device Technology) is a high-speed, 64K × 16-bit true dual-ported static RAM with independent left/right ports, 15 ns max access time (commercial grade), TTL-compatible 5V ±10% supply, and integrated hardware semaphore/arbiter logic for interprocessor communication. It enables simultaneous read access to the same memory location and supports master/slave configuration via M/S pin for 32-bit+ bus expansion in real-time embedded control systems.

For engineers reviewing the 7028L15PF8 datasheet, 7028L15PF8 pinout, 7028L15PF8 application, or 7028L15PF8 equivalent, key selection considerations include its dual-port arbitration timing (tBAA ≤15 ns), BUSY flag behavior under M/S = VIH/VIL, semaphore address mapping (A0–A2), and TQFP-100 package compatibility with industrial PCB layouts requiring deterministic inter-processor handshaking.

Technical Context

The 7028L15PF8 implements fully asynchronous dual-port operation with separate CE0/CE1, R/W, OE, UB/LB, and SEM controls per port-enabling independent read/write cycles without clock synchronization. Its on-chip arbitration logic uses push-pull BUSY outputs (not open-drain) and supports both address-match and CE-controlled BUSY assertion modes with tAPS = 5 ns priority setup.

Hardware semaphores reside in dedicated latches (not RAM array), accessed via CE = VIH & SEM = VIL using A0–A2, and support token-passing protocols across ports without software wait states. Interrupt flags (INTL/INTR) are triggered by writes to fixed addresses FFFE_H (left sets right flag) and FFFF_H (right sets left flag), with tINS/tINR ≤20 ns.

Key Specifications

Pinout & Package

7028L15PF8 is housed in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All VCC pins must be decoupled locally; all GND pins require low-impedance grounding per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-15ZXI and AS7C364096B-15TIN, the 7028L15PF8 uniquely delivers integrated hardware semaphores, push-pull BUSY outputs, and master/slave configurability-making it irreplaceable in deterministic real-time systems requiring sub-20 ns interprocessor coordination without external logic.

Availability

7028L15PF8 is available at Aetrix Electronics and suitable for industrial motion controllers, telecom line cards, avionics display systems, and medical imaging subsystems requiring stable component supply across extended production lifecycles.

Supply support for 7028L15PF8 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) was a fabless semiconductor company specializing in high-performance memory, timing, and interconnect solutions before its acquisition by Renesas Electronics in 2019.

The 7028L15PF8 belongs to IDT's legacy high-speed dual-port SRAM product line, designed specifically for deterministic interprocessor communication in real-time embedded systems requiring hardware-accelerated semaphore and arbitration logic.

FAQ

What is the maximum operating frequency supported by the 7028L15PF8?

The 7028L15PF8 does not operate on a clock signal-it is an asynchronous SRAM. Its performance is defined by access timing parameters: tRC = 15 ns (read cycle time), tWC = 15 ns (write cycle time), and tAA = 15 ns (address access time). These values establish a maximum effective throughput of ~66.7 MHz for consecutive random accesses, assuming optimal bus turnaround and no wait states. The 7028L15PF8 achieves this without clock distribution or skew management overhead.

How does the M/S pin affect BUSY pin functionality in the 7028L15PF8?

When M/S = VIH, the 7028L15PF8 operates as a Master: BUSYL and BUSYR are push-pull outputs that assert LOW during address contention to stall the contending port. When M/S = VIL, it operates as a Slave: BUSYL and BUSYR become inputs that must be driven externally (e.g., by another 7028L15PF8's BUSY output) to inhibit writes. This dual-mode design enables flexible cascading in multi-chip 32-bit or wider memory systems without external logic.

Can the 7028L15PF8 perform simultaneous reads from both ports to the same memory address?

Yes-the 7028L15PF8 uses true dual-ported memory cells that permit concurrent reads from the left and right ports to identical addresses with no timing penalty or data corruption. This capability is fundamental to its architecture and is explicitly guaranteed in the datasheet's "Features" section. Simultaneous read-to-same-address is fully supported at rated speed (15 ns access) and requires no special control sequencing.

What are the voltage thresholds for VIH and VIL on control inputs of the 7028L15PF8?

Per the Recommended DC Operating Conditions table, VIH = 2.2 V minimum (up to 6.0 V absolute max), and VIL = 0.8 V maximum (down to –0.5 V absolute min). These thresholds ensure reliable TTL-level compatibility: standard 5V TTL outputs (2.4–5.0 V for HIGH, 0–0.8 V for LOW) interface directly with the 7028L15PF8 without level shifters. Input leakage remains ≤5 µA across the full valid voltage range.

How are the semaphore flags addressed and accessed in the 7028L15PF8?

Semaphore flags are accessed exclusively when CE = VIH and SEM = VIL (per Truth Table III). Address bits A0–A2 select one of eight semaphore latches; I/O0 carries the write data (0 or 1), and all I/O0–I/O15 reflect the current flag state on read. This dedicated access path isolates semaphores from the main 64K×16 RAM array-ensuring atomic token-passing operations without affecting memory bandwidth or timing.