Renesas IDT79RV4640-133DUG

Overview

IDT79RV4640-133DUG from Integrated Device Technology is a 3.3V, 133 MHz, 64-bit MIPS III–compliant RISC microprocessor with integrated floating-point coprocessor, 8 KB instruction cache, and 8 KB data cache. It delivers 352 Dhrystone MIPS and 89 MFlops single-precision performance for embedded control and integer DSP workloads in internetworking and multimedia systems.

For engineers reviewing the IDT79RV4640-133DUG datasheet, IDT79RV4640-133DUG pinout, IDT79RV4640-133DUG application, or IDT79RV4640-133DUG equivalent, key selection criteria include its 133 MHz pipeline clock, 32-bit synchronized system bus interface, on-chip cache locking support, and software compatibility with IDT RC4000 family processors.

Technical Context

The IDT79RV4640-133DUG implements a 5-stage integer pipeline with dedicated 64-bit multiply/divide unit supporting 133.5 M Mul-Add/sec at full speed. Its floating-point coprocessor executes IEEE 754 single-precision operations-including ADD, MUL, DIV, SQRT-with latencies of 4–32 cycles and no double-precision hardware.

System-level integration includes CP0-based virtual-to-physical address translation via base/bound registers (no TLB required), two 8 KB 2-way set-associative caches with write-back/write-through policy, and a non-overlapping 32-bit system interface clocked up to 125 MHz with PLL-multiplied internal pipeline clock.

Key Specifications

Pinout & Package

Package: 256-pin Ceramic Pin Grid Array (CPGA), 35.56 mm × 35.56 mm, 1.27 mm pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar embedded RISC processor applications.

Compared with IDT79RV4640-133DUG, the 5V IDT79RC4640-133DUG trades lower power for robustness in industrial backplanes, while IDT79RC4650-133DUG adds MMU and cache capacity at the cost of higher die area and static power-making it optimal for complex OS environments but over-specified for bare-metal DSP control.

Availability

IDT79RV4640-133DUG is available at Aetrix Electronics and suitable for router control planes, industrial print controllers, DSP-accelerated game consoles, and medical imaging front-ends requiring stable component supply across long-lifecycle embedded programs.

Supply support for IDT79RV4640-133DUG 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 U.S.-based semiconductor company specializing in timing, memory interface, RF, and embedded processor solutions before its acquisition by Renesas Electronics in 2019.

IDT79RV4640-133DUG belongs to the RC4000 family of embedded RISC processors designed for cost-sensitive, high-throughput applications in internetworking, office automation, and consumer multimedia-emphasizing cache efficiency, integer DSP acceleration, and software compatibility over full MMU support.

FAQ

What is the operating voltage range for IDT79RV4640-133DUG?

IDT79RV4640-133DUG operates at a nominal 3.3 V supply with tolerance of ±0.3 V (3.0 V to 3.6 V). This defines its I/O voltage domain and mandates use of 3.3 V–compatible peripherals and level-shifting circuitry when interfacing with 5 V logic. The "RV" prefix explicitly denotes the 3.3 V variant within the RC4640 family, distinguishing it from the 5 V "RC" and mixed-voltage "R" versions. IDT79RV4640-133DUG's power management features-including standby mode and active unit gating-are optimized for this voltage range.

Does IDT79RV4640-133DUG support double-precision floating-point arithmetic?

No, IDT79RV4640-133DUG does not implement double-precision floating-point hardware. Its on-chip floating-point coprocessor supports only IEEE 754 single-precision operations (32-bit). Attempts to execute double-precision instructions or access double-precision registers trigger a trap exception, allowing software emulation. This design choice reduces die area and power consumption while maintaining binary compatibility with higher-end IDT processors like the RC4700. IDT79RV4640-133DUG relies on compiler-inserted library calls or kernel traps for double-precision needs.

How is cache locking implemented in IDT79RV4640-133DUG?

IDT79RV4640-133DUG implements cache locking exclusively on Set A of both instruction and data caches (each 4 KB). Locking is controlled via CP0 register bits (Config register bit 16 for instruction cache, CAlg register bits for data cache). When enabled, locked lines cannot be overwritten by cache misses, preserving critical code or data in deterministic real-time contexts. IDT79RV4640-133DUG does not support locking of Set B or partial-line locking-locking applies to entire 32-byte cache lines within the designated set.

Is IDT79RV4640-133DUG pin-compatible with other RC4640 variants?

Yes, IDT79RV4640-133DUG is socket-compatible with IDT RC64474 and RC64574 processors and shares identical pinout and package (256-pin CPGA) with IDT79RC4640-133DUG and IDT79R4640-133DUG. All RC4640 family members use the same mechanical footprint and electrical signaling conventions on SysAD, SysCmd, and handshake pins. However, voltage differences (3.3 V vs. 5 V) require corresponding changes to power delivery and I/O termination-so while PCB layout is reusable, schematic-level voltage translation may be needed.

What boot-time configuration options are available for IDT79RV4640-133DUG?

IDT79RV4640-133DUG initializes fundamental modes-including pipeline clock multiplier (2× to 8×), cache write policy, and bus timing parameters-via a 256-bit serial boot stream sampled after VCCOK assertion. This low-speed (MasterClock/256) interface allows configuration using a small EPROM or PAL. The boot stream is defined in IDT documentation as Table 6 and is independent of external memory map. IDT79RV4640-133DUG does not support JTAG-based runtime reconfiguration of these boot modes; they are fixed at power-on reset.