Renesas 70V27L55PF

Overview

70V27L55PF from Integrated Device Technology (IDT) is a high-speed, low-power 32K × 16 dual-port static RAM with true dual-port architecture enabling simultaneous independent read/write access to the same memory location from left and right ports. It operates on a single 3.3V ±0.3V supply, delivers 55ns maximum access time, supports industrial temperature range (−40°C to +85°C), and features on-chip semaphore logic and BUSY/INT flags for inter-processor communication in real-time embedded systems.

For engineers reviewing the 70V27L55PF datasheet, 70V27L55PF pinout, 70V27L55PF application, or 70V27L55PF equivalent, key selection criteria include its 55ns access timing under industrial conditions, 660μW standby power consumption, 100-pin TQFP package, LVTTL-compatible I/O, and hardware-supported port arbitration - all critical for deterministic multi-CPU memory sharing in avionics, industrial PLCs, and telecom line cards.

Technical Context

The 70V27L55PF implements fully asynchronous dual-port operation with separate address, control, and data buses per port (A0L–A14L/I/O0L–I/O15L and A0R–A14R/I/O0R–I/O15R), enabling concurrent access without external synchronization logic. Its on-chip arbitration logic resolves contention via address-match or chip-enable timing, asserting BUSY flags with defined tBAA/tBDA delays up to 45ns.

It integrates full semaphore signaling across eight flags (addressed by A0–A2), supporting atomic read-modify-write operations between ports. The device uses CMOS high-performance fabrication, supports master/slave cascading for 32-bit+ bus expansion via M/S pin, and provides four standby current modes (ISB1–ISB4) with sub-mA full-standby draw (0.2mA typ.) when both ports are disabled with CMOS-level inputs.

Key Specifications

Pinout & Package

70V27L55PF 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 VDD pins require local 3.3V decoupling; all VSS pins must be connected to solid ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-55AXC and R1EX24032ASAS-55X#U0, the 70V27L55PF uniquely delivers hardware semaphore support, industrial temperature qualification, and push-pull BUSY arbitration in a compact TQFP - making it the only choice for safety-critical, real-time deterministic systems requiring zero-software-latency inter-processor communication.

Availability

70V27L55PF is available at Aetrix Electronics and suitable for avionics flight control systems, industrial programmable logic controllers, and telecom line card buffering requiring stable component supply across long product lifecycles and rigorous environmental certification.

Supply support for 70V27L55PF 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, RF, and sensor signal conditioning ICs for communications, computing, and industrial markets.

The IDT70V27 family was designed specifically for deterministic, low-latency memory sharing between heterogeneous processors in safety-critical embedded systems - emphasizing hardware arbitration, ultra-low standby power, and industrial reliability over raw density or cost.

FAQ

What is the maximum operating frequency supported by the 70V27L55PF?

The 70V27L55PF does not operate on a clock signal - it is an asynchronous dual-port SRAM. Its performance is specified by access time: 55ns maximum read cycle time (tRC) under industrial conditions (−40°C to +85°C, VDD = 3.3V ±0.3V). This corresponds to a theoretical maximum sustained throughput of approximately 18.2 MHz for consecutive random accesses, though actual system bandwidth depends on bus protocol and controller timing margins. The 70V27L55PF datasheet confirms no clock input is required.

Does the 70V27L55PF support both master and slave configurations simultaneously?

No - the 70V27L55PF operates exclusively in one mode at a time, determined by the logic level applied to the M/S pin. When M/S = VIH, the device functions as a Master: BUSYL and BUSYR are active push-pull outputs used to arbitrate access from other slave devices. When M/S = VIL, it operates as a Slave: BUSYL and BUSYR become inputs that accept BUSY signals from a master device to inhibit writes. The 70V27L55PF cannot self-arbitrate as both master and slave in the same system configuration.

How is semaphore functionality implemented in the 70V27L55PF?

Semaphore functionality in the 70V27L55PF is implemented via eight dedicated hardware flags accessed through the I/O0–I/O15 pins and addressed by A0–A2. To write a semaphore flag, CE must be HIGH and SEM LOW; to read, CE must be HIGH and SEM LOW while driving the desired flag address (0–7) on A0–A2. The 70V27L55PF datasheet specifies tSOP (semaphore update pulse) as 15ns min and tSAA (semaphore address access) as 45ns max, ensuring atomic flag manipulation without software intervention.

What are the power consumption characteristics of the 70V27L55PF in standby mode?

In full standby mode (ISB3), where both ports are disabled with CMOS-level inputs (CE > VDD − 0.2V, all inputs at rail), the 70V27L55PF draws only 0.2 mA typical (6 μA max) at VDD = 3.3V and TA = +25°C. Under industrial conditions (−40°C to +85°C), ISB3 remains ≤3 mA max. This ultra-low standby current enables energy-efficient operation in battery-backed systems such as portable diagnostic tools and remote sensor gateways, where the 70V27L55PF can remain powered for months without significant drain.

Can the 70V27L55PF be used in a 32-bit data bus configuration?

Yes - the 70V27L55PF supports 32-bit bus expansion via its Master/Slave cascading capability. Two devices can be connected with M/S = VIH (Master) and M/S = VIL (Slave); the Master's BUSY output controls the Slave's BUSY input, enabling synchronized access. Upper/lower byte enables (UBL/LBL, UBR/LBR) allow interleaving of 16-bit words across both devices. The 70V27L55PF datasheet explicitly states "IDT70V27 easily expands data bus width to 32 bits or more using the Master/Slave select when cascading more than one device."