Renesas 70V658S15BC8

Overview

70V658S15BC8 from IDT is a high-speed 64K × 36 asynchronous dual-port static RAM with true independent left/right ports, 15 ns maximum access time, LVTTL-compatible 3.3 V core supply, and selectable 3.3 V/2.5 V I/O voltage per port-used in real-time inter-processor communication buffers for telecom line cards and industrial motion controllers.

For engineers reviewing the 70V658S15BC8 datasheet, 70V658S15BC8 pinout, 70V658S15BC8 application, or 70V658S15BC8 equivalent, key selection criteria include simultaneous dual-port arbitration latency, byte-enable granularity (four 9-bit bytes), JTAG IEEE 1149.1 compliance, and Master/Slave cascading support for 72-bit+ memory expansion without external logic.

Technical Context

This device implements fully asynchronous dual-port architecture with on-chip semaphore logic, independent CE0/CE1 and BE0–BE3 controls per port, and automatic power-down when either chip enable is deasserted. It supports concurrent read/write to the same memory location via hardware-enforced arbitration.

The M/S pin configures BUSY as output (Master) or input (Slave); BUSY and INT are non-tri-state totem-pole outputs. Each port's I/O voltage is independently set via OPTL/OPTR, enabling mixed-voltage system interfacing-e.g., 3.3 V left port to FPGA, 2.5 V right port to ASIC.

Key Specifications

Pinout & Package

70V658S15BC8 is packaged in a 208-ball fine-pitch BGA (BF208 package code), body size 15 mm × 15 mm × 1.4 mm, 0.8 mm ball pitch. All VSS pins require solid ground plane connection; VDD and VDDQ pins must be decoupled per layout guidelines.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-15ZXI and AS7C362000B-15JIN, the 70V658S15BC8 uniquely delivers per-port I/O voltage flexibility, integrated semaphore registers, and production-ready JTAG - reducing BOM count and validation effort in complex heterogeneous systems.

Availability

70V658S15BC8 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, and aerospace avionics requiring stable component supply across extended product lifecycles.

Supply support for 70V658S15BC8 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, and RF solutions, now part of Renesas Electronics since 2019.

The 70V659/58/57 family was designed for high-reliability, low-latency inter-processor communication in real-time embedded systems where deterministic memory access and hardware arbitration are critical.

FAQ

What is the memory organization of the 70V658S15BC8?

The 70V658S15BC8 implements a 64K × 36-bit asynchronous dual-port SRAM array. Address lines A0L–A15L and A0R–A15R provide full 16-bit addressing; A16L and A16R are no-connect pins per datasheet note 1, confirming the 64K depth (2¹⁶ = 65,536 words).

Does the 70V658S15BC8 support mixed-voltage operation between its two ports?

Yes, the 70V658S15BC8 supports independent I/O voltage selection per port via OPTL and OPTR pins. Setting OPTL to VDD enables 3.3 V I/O on the left port; setting OPTR to VSS enables 2.5 V I/O on the right port - allowing direct interfacing with heterogeneous logic families without external level shifters.

How does the Master/Slave configuration affect BUSY signal behavior in the 70V658S15BC8?

When M/S = VIH, the 70V658S15BC8 operates as Master: BUSYL and BUSYR become totem-pole outputs that assert during port contention. When M/S = VIL, it operates as Slave: BUSYL and BUSYR become inputs, accepting BUSY assertions from a Master device - enabling hierarchical arbitration in multi-SRAM systems.

What is the purpose of the semaphore logic in the 70V658S15BC8?

The 70V658S15BC8 integrates eight hardware semaphore flags accessible via I/O0–I/O35 using address bits A0–A2. These flags enable atomic resource locking between ports without software overhead - for example, flag #3 can reserve a shared DMA descriptor table, preventing race conditions during concurrent access.

Is JTAG debugging supported on the 70V658S15BC8, and what are the requirements?

Yes, the 70V658S15BC8 supports IEEE 1149.1 JTAG boundary-scan via TDI, TDO, TCK (≤10 MHz), TMS, and TRST pins. No special initialization is required beyond standard TAP controller reset; all JTAG functions are operational across the full industrial temperature range (–40°C to +85°C).