Renesas 70V28L20PFI

Overview

70V28L20PFI from Integrated Device Technology is a high-speed 3.3V 64K × 16 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. It operates across –40°C to +85°C and supports master/slave cascading for 32-bit+ bus expansion in real-time embedded control systems.

For engineers reviewing the 70V28L20PFI datasheet, 70V28L20PFI pinout, 70V28L20PFI application, or 70V28L20PFI equivalent, key selection criteria include simultaneous port arbitration timing (tAPS = 5 ns), BUSY flag behavior under M/S configuration, dual CE-controlled standby power (ISB3 = 0.2 mA typ.), and semaphore write-to-read latency (tSWRD = 5 ns).

Technical Context

The 70V28L20PFI implements fully asynchronous dual-port architecture with separate address, control, and bidirectional I/O buses per port. Its on-chip arbitration logic resolves contention via address-matching detection and push-pull BUSY flag assertion (not open-drain), with priority determined by tAPS setup timing.

Semaphore functionality uses eight dedicated latches addressed by A0–A2, accessed only when CE = VIH and SEM = VIL - independent of main memory array operation. Interrupt flags (INTL/INTR) are software-triggered via writes to FFFE_H/FFFF_H, enabling mailbox-style inter-processor signaling without external logic.

Key Specifications

Pinout & Package

70V28L20PFI is housed in a 100-pin Thin Quad Flatpack (TQFP) with 14 mm × 14 mm body and 1.4 mm height. All VCC and GND pins must be connected per datasheet Note 1–2; NC pins are internally unconnected and must not be tied.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-20AXC and AS7C364000B-20TIN, the 70V28L20PFI uniquely delivers integrated semaphore arbitration, push-pull BUSY signaling, and master/slave cascading - reducing BOM count by ≥3 discrete components and eliminating timing-critical software arbitration loops.

Availability

70V28L20PFI is available at Aetrix Electronics and suitable for industrial motion control, avionics data concentrators, medical imaging co-processors, automotive ADAS sensor fusion hubs, and real-time embedded systems requiring stable component supply with guaranteed long-term lifecycle support.

Supply support for 70V28L20PFI 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, designs high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The 70V28L20PFI belongs to IDT's legacy high-speed dual-port SRAM product line, engineered specifically for deterministic inter-processor communication in real-time embedded systems requiring hardware-enforced coherency.

FAQ

What is the operating temperature range for the 70V28L20PFI?

The 70V28L20PFI is rated for industrial temperature operation from –40°C to +85°C. This specification is validated per datasheet Section 3 (Recommended DC Operating Conditions) and applies to all timing parameters including tAA, tACE, and tBDD at 20 ns maximum. No derating is required within this range.

How does the BUSY arbitration logic function in master versus slave mode on the 70V28L20PFI?

In master mode (M/S = VIH), BUSYL and BUSYR are push-pull outputs that assert when opposing port accesses the same address - automatically inhibiting writes on the contending side. In slave mode (M/S = VIL), BUSYL/BUSYR become inputs that must be driven externally to gate writes; the 70V28L20PFI itself does not generate BUSY in this configuration.

Can the 70V28L20PFI support 32-bit data bus expansion, and how is it implemented?

Yes - the 70V28L20PFI supports 32-bit expansion via master/slave cascading. One device is configured as master (M/S = VIH) and another as slave (M/S = VIL); upper/lower byte enables (UBL/LBL, UBR/LBR) and CE chaining allow seamless width scaling without external logic, as documented in the Functional Description section.

What are the power consumption characteristics of the 70V28L20PFI in standby mode?

The 70V28L20PFI offers four standby current modes. Full CMOS standby (ISB3) draws 0.2 mA typical when both CEs are held > VCC − 0.2 V or < 0.2 V. TTL-level standby (ISB1) consumes 35 mA typical for industrial grade. These values are measured per Table 10 in the datasheet under VCC = 3.3 V ± 0.3 V.

How are the semaphore flags accessed and what addressing scheme do they use on the 70V28L20PFI?

Semaphore flags are accessed exclusively when CE = VIH and SEM = VIL - placing the device in semaphore mode. Eight flags are mapped to addresses A2–A0 (000 to 111), with data written via I/O0 and read across all I/O0–I/O15 lines. This dedicated bank operates independently of the main 64K × 16 memory array.