Renesas 7025L35PFI8

Overview

7025L35PFI8 from IDT (Integrated Device Technology) is a high-speed 8K × 16-bit true dual-port static RAM with independent asynchronous left/right ports, 35 ns maximum read cycle time, 1 mA typical standby current, and industrial temperature range (–40°C to +85°C). It supports simultaneous reads of the same memory location and is used in real-time inter-processor communication, video frame buffers, and military-grade embedded systems requiring deterministic arbitration.

For engineers reviewing the 7025L35PFI8 datasheet, 7025L35PFI8 pinout, 7025L35PFI8 application, or 7025L35PFI8 equivalent, key selection considerations include BUSY-flag arbitration timing (tBAA ≤ 20 ns), semaphore flag support (8 flags via A0–A2), battery backup data retention at 2 V, TTL-compatible 5 V ±10% supply, and 100-pin TQFP packaging for high-density PCB layouts.

Technical Context

The 7025L35PFI8 implements full on-chip hardware semaphore logic and port arbitration, enabling conflict-free concurrent access without external logic. Its dual-port architecture allows independent address, control, and I/O buses per port - left (L) and right (R) - each with dedicated CE, R/W, OE, UB/LB, SEM, INT, and BUSY signals.

It operates fully asynchronously: reads and writes may occur simultaneously on both ports, with BUSY assertion (when M/S = H) or BUSY input (when M/S = L) managing contention. The device supports two distinct operational modes - RAM array access (SEM = VIH) and semaphore register access (SEM = VIL) - with separate timing requirements for each.

Key Specifications

Pinout & Package

7025L35PFI8 is packaged in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, 14 mm × 14 mm body, and 1.4 mm height. Pin assignments follow the PNG100 package configuration as defined in IDT DSC 2683/13.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C136-35JC and AS7C38099B-35TIN, the 7025L35PFI8 uniquely integrates BUSY-flag arbitration, 8-bit semaphore registers, and 2 V data retention - making it the only option among the three that supports autonomous, low-power, fault-tolerant inter-processor communication without external components.

Availability

7025L35PFI8 is available at Aetrix Electronics and suitable for real-time inter-processor communication, video frame buffering, and military avionics data logging requiring stable component supply across extended product lifecycles.

Supply support for 7025L35PFI8 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 timing, memory interface, RF, and high-performance interconnect solutions, now part of Renesas Electronics.

The 7025L series was designed for deterministic, low-latency shared-memory architectures in defense, industrial automation, and broadcast video - emphasizing hardware arbitration, battery backup, and wide-temperature reliability.

FAQ

What is the maximum operating temperature range for the 7025L35PFI8?

The 7025L35PFI8 is rated for industrial temperature operation from –40°C to +85°C. This specification is confirmed in the Absolute Maximum Ratings table and DC Electrical Characteristics section of the IDT DSC 2683/13 datasheet. The device meets this range under full 5 V ±10% supply and all specified timing conditions, making it suitable for enclosed industrial controllers and avionics enclosures without forced cooling.

Does the 7025L35PFI8 support battery backup operation, and what voltage is required?

Yes, the 7025L35PFI8 supports battery backup data retention at 2.0 V (VDR), as specified in Table 10 of the datasheet. In data retention mode, ICCDR is guaranteed ≤ 4000 µA across military and industrial grades. This feature allows the 7025L35PFI8 to maintain valid memory contents during main power failure - a capability not present in the S-version (7025S) or most competing dual-port SRAMs.

How does the BUSY flag function in master versus slave configuration on the 7025L35PFI8?

When M/S = H, the 7025L35PFI8 operates as Master: BUSYR is an output that asserts when port contention occurs (e.g., simultaneous write to same address), blocking the slave port's R/W. When M/S = L, it operates as Slave: BUSYR becomes an input, accepting the BUSY signal from the Master to gate its own write operations. This dual-role behavior is intrinsic to the 7025L35PFI8's pinout and requires no external logic to cascade devices for wider data paths.

Can the 7025L35PFI8 be used in a 32-bit memory system, and how is that implemented?

Yes, the 7025L35PFI8 supports 32-bit expansion via Master/Slave cascading. One device is configured as Master (M/S = H) and others as Slaves (M/S = L); the Master's BUSYR output connects to Slave BUSYR inputs. Address and control lines are shared, while data buses are interleaved - e.g., Master handles I/O0–I/O15 and Slave handles I/O0–I/O15 of a second 7025L35PFI8 - achieving full-speed 32-bit access without added logic delay or timing skew.

What are the key timing parameters governing semaphore flag access on the 7025L35PFI8?

Semaphore access on the 7025L35PFI8 requires SEM = VIL, with CE or UB/LB = VIH (Table 3). Critical timing parameters include tSOP (semaphore update pulse ≥ 15 ns), tSAA (semaphore address access ≤ 35 ns), tSWRD (write-to-read delay ≥ 5 ns), and tSPS (contention window ≥ 5 ns). These values ensure atomic flag updates even under concurrent port access - a capability directly enabled by dedicated semaphore control logic internal to the 7025L35PFI8.