Renesas 70V631S10BCG8

Overview

70V631S10BCG8 from IDT (Integrated Device Technology) is a high-speed, fully asynchronous 256K × 18-bit dual-port static RAM with independent left/right ports, 10 ns max read cycle time, LVTTL-compatible 3.3 V core supply and selectable 3.3 V/2.5 V I/O supplies, and on-chip semaphore/arbitration logic for real-time inter-processor communication in embedded control systems.

For engineers reviewing the 70V631S10BCG8 datasheet, 70V631S10BCG8 pinout, 70V631S10BCG8 application, or 70V631S10BCG8 equivalent, this device is selected for deterministic low-latency memory sharing between two independent bus masters-especially where simultaneous access to shared data buffers, mailbox messaging, or hardware-enforced resource locking is required without external arbitration logic.

Technical Context

The 70V631S10BCG8 implements true dual-port SRAM cells enabling concurrent read/write operations on both ports without internal contention. Its port arbitration logic supports automatic BUSY flag generation during address-matching write conflicts and includes dedicated INTL/INTR interrupt outputs triggered by specific address writes.

Each port features independent chip enables (CE0X/CE1X), byte controls (UBX/LBX), and R/WX signals, with OPTX pins selecting 3.3 V or 2.5 V I/O voltage per port. JTAG is omitted in this 256-ball BGA package due to pin count constraints, but full IEEE 1149.1 support exists in higher-pin-count variants.

Key Specifications

Pinout & Package

70V631S10BCG8 is housed in a 256-ball fine-pitch BGA (package code BCG256), with power/ground distributed across multiple VDD, VDDQ, and VSS balls for low-noise operation. Pin functions are strictly defined per port (left/right), with dedicated I/O banks (I/O0L–I/O17L, I/O0R–I/O17R), independent address buses (A0L–A17L, A0R–A17R), and dual-control sets including CE0/CE1, R/W, OE, UB/LB, SEM, INT, and BUSY per side.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-10AXC and AS7C3256A-10TIN, the 70V631S10BCG8 delivers unique value through its 18-bit width, per-port 2.5 V/3.3 V I/O flexibility, integrated semaphore, and deterministic BUSY arbitration - making it irreplaceable in tightly coupled multi-processor systems requiring hardware-enforced coherency.

Availability

70V631S10BCG8 is available at Aetrix Electronics and suitable for industrial PLCs, automotive ADAS domain controllers, aerospace health monitoring units, and medical imaging subsystems requiring stable component supply across extended product lifecycles.

Supply support for 70V631S10BCG8 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 70V631S10BCG8 belongs to IDT's high-speed asynchronous dual-port SRAM product line, engineered specifically for deterministic, low-latency inter-processor communication in safety-critical and real-time embedded systems.

FAQ

What is the maximum operating frequency supported by the 70V631S10BCG8?

The 70V631S10BCG8 does not operate on a clock signal-it is fully asynchronous. Its performance is specified by access times: 10 ns maximum read cycle time (tRC) and 10 ns maximum address access time (tAA) under commercial conditions. This enables reliable interface with controllers running up to ~100 MHz system clocks when accounting for setup/hold margins and PCB trace delays.

Does the 70V631S10BCG8 support JTAG boundary scan?

No. Although the 70V631S10BCG8 supports IEEE 1149.1 JTAG features in architecture, JTAG is explicitly disabled in the 256-ball BGA package (BCG256) due to insufficient pin count. Pins TDI, TDO, TCK, TMS, and TRST are present but not functional in this variant, as confirmed in the datasheet note on page 3.

How is the BUSY signal used in master/slave configuration with the 70V631S10BCG8?

In master mode (M/S = VIH), BUSYR is an output that asserts within 10 ns (tBAA) when the right port attempts a write to an address currently being written by the left port. In slave mode (M/S = VIL), BUSYR becomes an input; the external master must monitor it and delay writes until BUSYR de-asserts, ensuring conflict-free access as defined in the timing waveforms on pages 15–16 of the datasheet.

Can both ports of the 70V631S10BCG8 operate at different I/O voltages simultaneously?

Yes. OPTL and OPTR are independent; setting OPTL = VIH and OPTR = VIL configures the left port for 3.3 V I/O levels (requiring VDDQL = 3.3 V) and the right port for 2.5 V I/O levels (requiring VDDQR = 2.5 V). This is explicitly supported per datasheet note on page 5 and enables seamless interfacing with heterogeneous host devices.

What is the function of the semaphore feature in the 70V631S10BCG8?

The 70V631S10BCG8 integrates eight hardware semaphore flags accessible via I/O0–I/O17 using address lines A0–A2. When SEMX = VIL and CEX = VIH, writes to these addresses atomically set/clear flags, allowing one port to signal resource availability to the other without polling or shared memory corruption-critical for real-time OS task synchronization.