Renesas 70V639S10PRFG

Overview

IDT70V639S10PRFG from Integrated Device Technology (IDT) is a high-speed, asynchronous dual-port static RAM with 128K × 18-bit organization (2,304 Kbit), operating at 3.3 V core supply and supporting independent 2.5 V or 3.3 V I/O on each port. It enables true simultaneous read/write access to the same memory location via left and right ports, features on-chip arbitration, semaphore logic, and BUSY/INT flags - used in real-time interprocessor communication, FPGA co-processor buffering, and legacy bus bridging systems.

For engineers reviewing the IDT70V639S10PRFG datasheet, IDT70V639S10PRFG pinout, IDT70V639S10PRFG application, or IDT70V639S10PRFG equivalent, key selection considerations include its 10 ns max read cycle time, dual-voltage I/O flexibility per port (2.5 V/3.3 V), Master/Slave cascading capability for 36-bit+ data width, and industrial-grade temperature support (–40°C to +85°C) in the 128-pin TQFP package.

Technical Context

The IDT70V639S10PRFG implements fully asynchronous dual-port architecture with independent address, control, and data buses per port. Its on-chip arbitration logic resolves contention using BUSY flag signaling, while semaphore registers (A0–A2 addressed) provide hardware-mutex coordination between ports without external logic.

Each port supports selectable I/O voltage (2.5 V or 3.3 V) via dedicated OPTL/OPTR pins and corresponding VDDQL/VDDQR supplies. The device operates with LVTTL-compatible timing and includes JTAG test interface - though omitted in the 128-pin TQFP variant per datasheet note.

Key Specifications

Pinout & Package

Package: 128-pin TQFP (PK128), 14 mm × 20 mm × 1.4 mm body, 0.5 mm lead pitch. All VDD pins require 3.3 V; VDDQL/VDDQR must match OPTL/OPTR voltage selection (2.5 V or 3.3 V); all VSS pins grounded.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371BV33-100AXC and AS7C3128B-10JIN, the IDT70V639S10PRFG uniquely delivers per-port I/O voltage selection, integrated semaphore registers, and configurable Master/Slave arbitration - enabling robust, low-latency inter-processor communication without external components.

Availability

IDT70V639S10PRFG is available at Aetrix Electronics and suitable for real-time interprocessor communication, FPGA-CPU shared memory buffering, and legacy bus bridging requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for IDT70V639S10PRFG 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) was a fabless semiconductor company specializing in timing, memory interface, RF, and power management ICs before its acquisition by Renesas Electronics in 2019. IDT pioneered high-performance dual-port SRAM architectures for real-time embedded systems.

The IDT70V639S product line was engineered for deterministic, low-latency inter-processor communication in telecom infrastructure, industrial automation, and military/aerospace systems - emphasizing hardware arbitration, voltage flexibility, and industrial reliability.

FAQ

What is the maximum operating speed of the IDT70V639S10PRFG?

The IDT70V639S10PRFG is rated for a maximum read cycle time of 10 ns (100 MHz effective), with guaranteed commercial-grade performance across 0°C to +70°C. Its 10 ns specification applies to address access (tAA), chip enable access (tACE), and read cycle (tRC) - validated under 3.3 V core and 3.3 V or 2.5 V I/O conditions per port.

Does the IDT70V639S10PRFG support both 2.5 V and 3.3 V I/O on the same device?

Yes - the IDT70V639S10PRFG supports independent I/O voltage selection per port: OPTL sets left-port I/O voltage (2.5 V or 3.3 V), and OPTR sets right-port I/O voltage. Corresponding VDDQL and VDDQR supplies must match the selected level. This allows one port to interface with a 2.5 V FPGA bank while the other connects to a 3.3 V microcontroller.

How does the Master/Slave configuration work on the IDT70V639S10PRFG?

The M/S pin configures BUSY behavior: when tied high (VIH), the device operates as Master and asserts BUSYR/BUSYL as outputs during port contention; when tied low (VIL), it acts as Slave and accepts BUSY as inputs. Cascading multiple IDT70V639S10PRFG devices in Master/Slave mode enables synchronized 36-bit+ memory expansion without external arbitration logic.

Can the IDT70V639S10PRFG be used for hardware semaphore synchronization?

Yes - the IDT70V639S10PRFG integrates eight dedicated semaphore flags accessible via A0–A2 addresses on either port. When SEM=VIL and CE=VIH, writes to I/O0 update the semaphore; reads return the value across all I/O lines. This provides atomic, lock-free inter-processor coordination without software overhead or external latches.

Is JTAG supported on the IDT70V639S10PRFG in the 128-pin TQFP package?

No - JTAG (IEEE 1149.1) is explicitly disabled in the 128-pin TQFP package (PK128) due to pin count limitations, as confirmed in the datasheet footnote on page 3. JTAG pins (TCK, TMS, TDI, TDO, TRST) are present but non-functional in this variant; functional JTAG is only available on the 208-ball and 256-ball BGA packages.