Renesas 70V659S10BC

Overview

70V659S10BC from IDT is a high-speed 128K × 36 asynchronous dual-port static RAM with true independent left/right ports, 10 ns max read/write cycle time (commercial grade), LVTTL-compatible I/Os, and on-chip semaphore arbitration logic. It operates from a 3.3 V core supply with selectable 3.3 V or 2.5 V I/O voltage per port and supports industrial temperature range (–40°C to +85°C) in selected speed grades - used in real-time DSP co-processing, FPGA memory bridging, and redundant control systems.

For engineers reviewing the 70V659S10BC datasheet, 70V659S10BC pinout, 70V659S10BC application, or 70V659S10BC equivalent, this page delivers verified functional architecture, validated port arbitration behavior, confirmed 208-pin PQFP package mapping, and precise timing constraints for simultaneous access, BUSY flag coordination, and JTAG-compliant boundary scan.

Technical Context

The 70V659S10BC implements fully asynchronous dual-port operation: each port has independent address, data, and control lines (CE0/CE1, R/W, OE, BE0–BE3), enabling concurrent read/write to the same memory location without external arbitration logic. Its on-chip arbitration uses dedicated SEM, BUSY, and INT signals with Master/Slave (M/S) configuration to resolve contention.

It integrates IEEE 1149.1-compliant JTAG test circuitry (TCK/TMS/TDI/TDO/TRST), supports per-port I/O voltage selection via OPTL/OPTR pins, and provides four 9-bit byte enables for granular 36-bit bus matching. The device features automatic power-down when either CE0 or CE1 is deasserted, reducing standby current to ≤15 mA in full CMOS standby mode.

Key Specifications

Pinout & Package

70V659S10BC is packaged in a 208-pin Plastic Quad Flatpack (PQFP), body size ≈28 mm × 28 mm × 3.5 mm, with 0.5 mm lead pitch. All VDD pins require connection to 3.3 V; VDDQL/VDDQR must match OPTL/OPTR settings (3.3 V or 2.5 V); all VSS pins connect to ground.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-10ZXC and AS7C312836B-12TCN, the 70V659S10BC uniquely combines 10 ns performance, per-port I/O voltage selection, integrated JTAG, and hardware semaphore - making it the only option supporting mixed-voltage, testable, lock-free dual-processor designs in a 208-pin PQFP.

Availability

70V659S10BC is available at Aetrix Electronics and suitable for industrial automation controllers, telecom infrastructure equipment, and aerospace data concentrators requiring stable component supply across extended product lifecycles.

Supply support for 70V659S10BC 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, RF, and sensor solutions, now part of Renesas Electronics.

The 70V659S10BC belongs to IDT's high-speed asynchronous dual-port SRAM family, designed specifically for deterministic, low-latency shared memory in real-time embedded systems with multi-processor or FPGA-CPU architectures.

FAQ

What is the maximum operating frequency supported by the 70V659S10BC?

The 70V659S10BC does not operate on a clock signal - it is an asynchronous device. Its performance is specified by access times: tAA and tWC are guaranteed ≤10 ns (commercial grade), enabling effective operation at up to ~100 MHz sustained bus rates when interfaced with appropriate setup/hold margins. Timing is controlled by CE, R/W, and OE transitions, not a system clock.

Does the 70V659S10BC support both 3.3 V and 2.5 V I/O voltages simultaneously on different ports?

Yes. The 70V659S10BC supports independent I/O voltage selection per port: OPTL sets the left port's I/O voltage (3.3 V if tied to VDD, 2.5 V if tied to VSS), and OPTR does the same for the right port. Corresponding VDDQL and VDDQR supplies must match those selections. This enables direct interfacing with 2.5 V FPGAs and 3.3 V microcontrollers without level shifters.

How does the BUSY flag function in Master/Slave configuration for the 70V659S10BC?

When M/S = VIH, the 70V659S10BC operates as Master: BUSYL/BUSYR are outputs that assert when the opposite port initiates a write to the same address. When M/S = VIL, it operates as Slave: BUSYL/BUSYR become inputs, and the external Master drives them to block writes during contention. This hardware handshake prevents data corruption without software intervention.

Can the 70V659S10BC be used in a single-port configuration?

Yes. Either port (left or right) can be disabled by holding both CE0X and CE1X high (VIH), placing that side in low-power standby. The remaining active port functions as a standard asynchronous SRAM with full 36-bit width, byte enables, and 10 ns access - useful for migration paths or partial-feature designs.

What is the purpose of the semaphore register in the 70V659S10BC?

The 70V659S10BC includes eight dedicated semaphore flags accessible via A0–A2 and I/O0. They are written by one port (with SEM = VIL, CE = VIH) and read by both ports (with SEM = VIH, CE = VIL). This hardware mechanism enables atomic resource locking - for example, reserving a memory region or signaling task completion - without CPU intervention or bus locking.