Renesas 70V38L20PFI

Overview

70V38L20PFI from Integrated Device Technology is a high-speed, 3.3V, 64K × 18 true dual-ported static RAM with independent left/right ports, 20 ns max access time (industrial grade), LVTTL-compatible I/O, and on-chip semaphore/arbiter logic for inter-processor synchronization in real-time embedded systems.

For engineers reviewing the 70V38L20PFI datasheet, 70V38L20PFI pinout, 70V38L20PFI application, or 70V38L20PFI equivalent, this device supports simultaneous asynchronous read/write to shared memory locations, hardware BUSY arbitration, interrupt flag signaling, and master/slave cascading for 36-bit+ bus expansion - critical for multi-CPU industrial controllers and telecom packet buffers.

Technical Context

The 70V38L20PFI implements fully asynchronous dual-port operation with separate CE0/CE1, R/W, OE, UB/LB, and SEM controls per port, enabling concurrent access without clock coordination. Its on-chip arbitration logic uses push-pull BUSY outputs (not open-drain) and supports both master (BUSY output) and slave (BUSY input) modes via the M/S pin.

It integrates eight dedicated semaphore latches addressable via A0–A2, writable by one port and readable by both, with tSPS = 5 ns contention window and tSWRD = 5 ns write-to-read latency. Interrupt flags (INTL/INTR) are triggered by writes to FFFE_H (left) or FFFF_H (right), supporting mailbox-style inter-processor messaging.

Key Specifications

Pinout & Package

70V38L20PFI 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 and GND pins must be connected per layout guidelines; package supports standard reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371BV33-200BZI and AS7C362000B-20TIN, the 70V38L20PFI uniquely integrates arbitration, semaphore, and interrupt logic in a single 100-pin TQFP - reducing BOM count and PCB area while guaranteeing deterministic inter-processor timing in safety-critical systems.

Availability

70V38L20PFI is available at Aetrix Electronics and suitable for industrial motion controllers, telecom line cards, avionics data concentrators, and medical imaging subsystems requiring stable component supply across extended product lifecycles.

Supply support for 70V38L20PFI 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), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, and RF power solutions for high-performance computing and communications infrastructure.

The 70V38L20PFI belongs to IDT's legacy high-speed dual-port SRAM product line, engineered specifically for deterministic, low-latency inter-processor communication in real-time embedded systems where hardware arbitration and semaphore coherency are mandatory.

FAQ

What is the operating temperature range of the 70V38L20PFI?

The 70V38L20PFI is rated for industrial temperature operation from −40°C to +85°C, verified across all electrical parameters including 20 ns access time, BUSY arbitration timing, and standby current. This makes it suitable for deployment in uncontrolled environments such as factory automation cabinets or outdoor telecom base stations where ambient temperatures exceed commercial limits.

How does the BUSY arbitration logic function in the 70V38L20PFI?

In master mode (M/S = VIH), the 70V38L20PFI asserts BUSYL or BUSYR when both ports access the same memory address concurrently; the signal disables writes on the delayed port until completion. In slave mode (M/S = VIL), BUSY becomes an input that gates local writes - allowing hierarchical arbitration in multi-device arrays. The logic guarantees tBDD ≤ 17 ns disable-to-valid-data delay.

Can the 70V38L20PFI be used for 36-bit or wider data bus expansion?

Yes - the 70V38L20PFI supports master/slave cascading via the M/S pin and dual CE enables. When configured as master, it drives BUSY to slave devices; when cascaded, multiple 70V38L20PFI units deliver full-speed 36-bit+ word access without external logic, as confirmed in the functional description and pin configuration diagrams.

What are the key timing differences between the 70V38L20PFI and the 70V38L15 version?

The 70V38L20PFI guarantees 20 ns max access time (tAA, tACE, tABE) across industrial temperature, while the 70V38L15 offers 15 ns max but only for commercial (0°C to +70°C) operation. Both share identical pinout, feature set, and DC specs; the 70V38L20PFI is the only version qualified for −40°C to +85°C with full AC timing compliance.

How are the semaphore flags accessed and used in the 70V38L20PFI?

Semaphore flags are accessed by setting SEM = VIL and addressing A0–A2 (8 locations); I/O0 writes the flag value, and all I/O0–I/O17 reflect its state. The 70V38L20PFI uses these latches for token-passing allocation - e.g., one CPU writes "0" to claim a resource, the other reads the flag before accessing shared memory, with tSPS = 5 ns contention window ensuring deterministic resolution.