Renesas 70V27L15BF

Overview

70V27L15BF from Integrated Device Technology is a high-speed 3.3V 32K × 16 dual-ported static RAM with true simultaneous access to the same memory location, 15 ns maximum read cycle time (tRC), 660 µW typical standby power, and industrial temperature support (–40°C to +85°C). It serves as a stand-alone or master/slave-configured memory in real-time embedded systems requiring deterministic inter-processor communication.

For engineers reviewing the 70V27L15BF datasheet, 70V27L15BF pinout, 70V27L15BF application, or 70V27L15BF equivalent, this page delivers verified timing specs, dual-port arbitration behavior, semaphore signaling capability, BUSY/INT flag operation, and TQFP-100 package interface details essential for multi-CPU memory coherency design.

Technical Context

The 70V27L15BF implements fully asynchronous dual-port architecture with independent left/right address, control, and I/O buses - enabling concurrent read/write operations without internal arbitration delay. Its on-chip port arbitration logic resolves contention via address-match or chip-enable priority, with programmable M/S pin selecting master (BUSY output) or slave (BUSY input) mode.

It integrates full hardware semaphore support across eight flags addressed by A0–A2, with dedicated SEM pins and non-tri-state totem-pole BUSY/INT outputs. The device uses LVTTL-compatible inputs and operates from a single 3.3V ±0.3V supply, with automatic power-down controlled per-port by CE0/CE1 enables.

Key Specifications

Pinout & Package

70V27L15BF is housed in a 100-pin TQFP (PN100-1) with 0.5 mm pitch, 14 mm × 14 mm footprint, and 1.4 mm height. All VDD pins require local decoupling; all VSS pins must be solidly grounded.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-15AC and R1EX24032ASAS-15, the 70V27L15BF uniquely combines on-chip semaphore, configurable BUSY I/O, and 660 µW standby power - delivering lower BOM count, reduced firmware latency, and extended operational uptime in resource-constrained dual-processor systems.

Availability

70V27L15BF is available at Aetrix Electronics and suitable for real-time motor control, dual-core DSP communication, and industrial PLC I/O mapping requiring stable component supply across long-life embedded programs.

Supply support for 70V27L15BF 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 IDT70V27 family was engineered specifically for deterministic inter-processor communication in hard real-time systems - emphasizing low-latency arbitration, hardware synchronization primitives, and industrial-grade reliability.

FAQ

What is the maximum operating frequency supported by the 70V27L15BF?

The 70V27L15BF does not specify a clock frequency; it is an asynchronous SRAM. Its speed is defined by timing parameters - notably 15 ns maximum read cycle time (tRC) and 15 ns maximum address access time (tAA). These values establish that the device supports effective memory access rates up to approximately 66.7 MHz in tightly controlled read cycles, assuming zero setup/hold overhead. Actual system throughput depends on bus protocol, controller timing margins, and contention handling.

Does the 70V27L15BF support byte-write masking, and how is it implemented?

Yes, the 70V27L15BF supports independent upper- and lower-byte write control via dedicated UBL/LBL (left port) and UBR/LBR (right port) inputs. When UBL = L and LBL = H, only the lower byte (I/O0–I/O7L) is written; when UBL = H and LBL = L, only the upper byte (I/O8–I/O15L) is written. This enables precise 8-bit updates in 16-bit systems without read-modify-write cycles - critical for efficient peripheral register shadowing.

How does the BUSY signal behave in master versus slave configuration on the 70V27L15BF?

When M/S = VIH (Master), BUSYL and BUSYR are push-pull outputs that assert LOW during port-to-port contention - blocking writes on the contending port. When M/S = VIL (Slave), BUSYL and BUSYR become inputs; a LOW level externally applied inhibits writes internally. The 70V27L15BF's dual-role BUSY eliminates need for external logic to manage arbitration directionality - a key differentiator from basic dual-port SRAMs.

Can the 70V27L15BF be used in a 32-bit data path, and what is required?

Yes, the 70V27L15BF supports 32-bit expansion via its Master/Slave cascade capability. Two devices are connected with M/S = VIH on the master (generating BUSY) and M/S = VIL on the slave (accepting BUSY). The master's BUSY output connects to the slave's BUSY input, and the master's INT output can drive the slave's INT input. This configuration maintains full-speed operation without external glue logic - enabling seamless 32-bit word access across both devices.

What are the voltage and current requirements for reliable operation of the 70V27L15BF?

The 70V27L15BF requires a single 3.3 V ±0.3 V supply (3.0 V to 3.6 V), with all VDD pins decoupled locally using 0.1 µF ceramic capacitors. Typical active current is 170 mA (70V27L version at 15 ns), while full standby current is only 0.2 mA. Input voltages must stay within –0.3 V to VDD+0.3 V; exceeding these ranges risks latch-up or parametric shift. Ground connections must be low-impedance to prevent noise-induced timing violations.