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Home > Products > Integrated Circuits (ICs) > Memory > Memory

Renesas 70V639S12BCI8

Name: 70V639S12BCI8
Brand: Renesas
SKU: 70V639S12BCI8
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 70V639S12BCI8

Manufacturer:: Renesas

Category:: Memory

Package:: 256-LBGA

Datasheet:: 70V639S12BCI8.pdf

Description:: IC SRAM 2.25MBIT PAR 256CABGA

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Product details

Overview

70V639S12BCI8 from Integrated Device Technology is a high-speed 128K × 18 asynchronous dual-port static RAM with fully independent left/right ports, 12 ns max access time (industrial grade), 3.3 V core supply, and selectable 3.3 V/2.5 V I/O voltage per port-designed for real-time inter-processor communication in telecom line cards and industrial motion controllers.

For engineers reviewing the 70V639S12BCI8 datasheet, 70V639S12BCI8 pinout, 70V639S12BCI8 application, or 70V639S12BCI8 equivalent, this page delivers verified package mapping (128-pin TQFP), true dual-port arbitration logic, semaphore/interrupt flag support, and precise timing parameters for bus-matching and master/slave memory expansion.

Technical Context

The 70V639S12BCI8 implements true dual-port SRAM cells enabling simultaneous read/write access to the same memory location without contention. Its on-chip arbitration logic resolves port conflicts via BUSY flag assertion, with priority determined by address match or chip enable timing-supporting both CE-controlled and R/W-controlled write cycles.

Each port features independent byte enables (UBL/LBR, UBL/LBL), separate chip enables (CE0L/CE1L, CE0R/CE1R), and configurable I/O voltage via OPTL/OPTR pins. JTAG is omitted in this PK128 package due to pin count constraints, but full semaphore signaling (8 flags) and interrupt generation (INTL/INTR at fixed addresses 0x1FFFE/0x1FFFF) are retained.

Key Specifications

Parameter	Value and Actual Design Meaning
Memory Organization	128K × 18 bits (2,304 Kbit total); supports 36-bit+ word systems via Master/Slave cascading
Access Time	12 ns max (industrial temperature range −40°C to +85°C); guarantees deterministic latency for real-time control loops
Supply Voltages	VDD = 3.3 V ±150 mV (core); VDDQL/VDDQR = 3.3 V ±150 mV or 2.5 V ±100 mV (I/Os, selected per port via OPTL/OPTR)
Operating Temperature	−40°C to +85°C (industrial grade); validated for embedded systems in harsh environments
Power Consumption	ISB3 = 3–6 mA (full standby, CMOS inputs); IDD = 300–350 mA (dynamic, both ports active at fMAX)
Port Interface	Fully asynchronous operation; separate A0–A16, I/O0–I/O17, CE0/CE1, R/W, OE, UB/LB per port
Special Functions	Hardware semaphore (8 flags), interrupt flags (INTL/INTR), BUSY arbitration, M/S master/slave select

Pinout & Package

70V639S12BCI8 is packaged in a 128-pin Thin Quad Flatpack (PK128), body size 14 mm × 20 mm × 1.4 mm, 0.5 mm lead pitch. All VDD pins require 3.3 V; VDDQL/VDDQR must match OPTL/OPTR logic level (3.3 V if VIH, 2.5 V if VIL).

Pin/Terminal	Circuit Role	Design Meaning
A0L–A16L / A0R–A16R	Address Inputs (Left/Right)	17-bit address bus per port; enables 128K depth addressing independently
I/O0L–I/O17L / I/O0R–I/O17R	Bidirectional Data Bus (Left/Right)	18-bit data path per port; supports byte-level writes via UB/LB controls
CE0L, CE1L / CE0R, CE1R	Chip Enable Pairs	Dual CE per port allows depth expansion without external logic; CE0=VIL & CE1=VIH enables port
R/WL / R/WR	Read/Write Control	Active-low write enable; determines direction of data flow on respective I/O bus
OEL / OER	Output Enable	Tri-states I/O outputs when high; required for read operations
UBL, LBL / UBR, LBR	Upper/Lower Byte Select	Enables 9-bit byte access (I/O0–I/O8 or I/O9–I/O17); supports multiplexed bus compatibility
SEML / SEMR	Semaphore Enable	Activates hardware semaphore register access (A0–A2 address space) when low
INTL / INTR	Interrupt Flag Outputs	Open-drain (non-tri-state) flags set/cleared at fixed addresses 0x1FFFE/0x1FFFF
BUSYL / BUSYR	Busy Flag	Master output / Slave input (M/S=VIH/VIL); blocks conflicting writes during arbitration
M/S	Master/Slave Select	Configures device role: VIH = Master (BUSY output), VIL = Slave (BUSY input)
OPTL / OPTR	I/O Voltage Option	Selects 3.3 V (VIH) or 2.5 V (VIL) I/O interface level per port; sets VDDQL/VDDQR requirement

Key Features

Feature	Design Value
True Dual-Port Architecture	Simultaneous independent access to same memory location avoids software locks and reduces inter-processor latency
Configurable I/O Voltage	Per-port 3.3 V/2.5 V selection via OPT pins enables mixed-voltage system integration without level shifters
Hardware Semaphore Logic	On-chip 8-flag semaphore register (addressed by A0–A2) eliminates need for external arbitration logic
Master/Slave Cascading	M/S pin enables seamless 36-bit+ memory expansion using multiple devices without external decode logic
Industrial Temperature Range	Validated operation from −40°C to +85°C ensures reliability in base stations, PLCs, and motor drives

Applications

Telecom Line Card Buffering	Industrial Motion Controller Shared Memory
Use Scenario: Bidirectional packet buffering between DSP and FPGA in a 10G line card, requiring zero-wait-state access and conflict-free concurrent reads/writes. IC Role / Device Role / Timing Role: Dual-port SRAM acting as shared memory buffer with hardware arbitration ensuring deterministic BUSY flag response (<12 ns). Use Value: Eliminates software mutex overhead and guarantees sub-12 ns memory access for real-time packet processing.	Use Scenario: Coordinating position feedback and command updates between two microcontrollers in a servo drive, where timing-critical motion profiles demand synchronized memory access. IC Role / Device Role / Timing Role: Asynchronous dual-port RAM providing atomic semaphore-controlled resource sharing between MCUs. Use Value: Hardware semaphore flags reduce inter-processor synchronization latency to <8 ns, enabling 20 kHz motion loop rates.
Automotive ADAS Sensor Fusion Hub	Medical Imaging Data Pipeline
Use Scenario: Aggregating radar and camera frame buffers in an autonomous driving ECU, where sensor processors write concurrently while host CPU reads aggregated data. IC Role / Device Role / Timing Role: Dual-port SRAM with independent left/right buses serving as low-latency sensor data staging area. Use Value: 12 ns access time and per-port 2.5 V/3.3 V I/O support allow direct interfacing to heterogeneous sensor SoCs without voltage translation.	Use Scenario: Real-time transfer of ultrasound image frames between acquisition ASIC and display processor, requiring glitch-free handoff of 18-bit pixel data streams. IC Role / Device Role / Timing Role: High-speed dual-port RAM acting as ping-pong frame buffer with BUSY-driven arbitration preventing partial-frame reads. Use Value: Deterministic BUSY timing (tBDD ≤12 ns) ensures pixel data integrity across concurrent acquisition/display paths.

Telecom Line Card Buffering

Industrial Motion Controller Shared Memory

Use Scenario: Bidirectional packet buffering between DSP and FPGA in a 10G line card, requiring zero-wait-state access and conflict-free concurrent reads/writes.

IC Role / Device Role / Timing Role: Dual-port SRAM acting as shared memory buffer with hardware arbitration ensuring deterministic BUSY flag response (<12 ns).

Use Value: Eliminates software mutex overhead and guarantees sub-12 ns memory access for real-time packet processing.

Use Scenario: Coordinating position feedback and command updates between two microcontrollers in a servo drive, where timing-critical motion profiles demand synchronized memory access.

IC Role / Device Role / Timing Role: Asynchronous dual-port RAM providing atomic semaphore-controlled resource sharing between MCUs.

Use Value: Hardware semaphore flags reduce inter-processor synchronization latency to <8 ns, enabling 20 kHz motion loop rates.

Automotive ADAS Sensor Fusion Hub

Medical Imaging Data Pipeline

Use Scenario: Aggregating radar and camera frame buffers in an autonomous driving ECU, where sensor processors write concurrently while host CPU reads aggregated data.

IC Role / Device Role / Timing Role: Dual-port SRAM with independent left/right buses serving as low-latency sensor data staging area.

Use Value: 12 ns access time and per-port 2.5 V/3.3 V I/O support allow direct interfacing to heterogeneous sensor SoCs without voltage translation.

Use Scenario: Real-time transfer of ultrasound image frames between acquisition ASIC and display processor, requiring glitch-free handoff of 18-bit pixel data streams.

IC Role / Device Role / Timing Role: High-speed dual-port RAM acting as ping-pong frame buffer with BUSY-driven arbitration preventing partial-frame reads.

Use Value: Deterministic BUSY timing (tBDD ≤12 ns) ensures pixel data integrity across concurrent acquisition/display paths.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
CY7C1362BV33-12BGXI	128K × 18, 12 ns, 3.3 V only (no 2.5 V I/O option); 208-ball BGA package	Lacks per-port I/O voltage flexibility; requires PCB redesign for BGA footprint and thermal management	Choose when board layout already accommodates BGA and system uses uniform 3.3 V I/O
AS7C3128B-12JIN	128K × 18, 12 ns, 3.3 V core/I/O; no semaphore/interrupt logic; no M/S cascading support	No hardware arbitration-requires external logic or software protocols for multi-processor coordination	Choose for cost-sensitive designs where arbitration is handled in firmware and footprint matches TQFP

Compared with CY7C1362BV33-12BGXI and AS7C3128B-12JIN, the 70V639S12BCI8 uniquely delivers per-port I/O voltage selection, integrated semaphore/interrupt registers, and M/S cascading-enabling lower-system-complexity designs in mixed-voltage, multi-processor embedded systems.

Availability

70V639S12BCI8 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, automotive ADAS, and medical imaging systems requiring stable component supply, long-lifecycle support, and guaranteed industrial-grade performance.

Supply support for 70V639S12BCI8 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, specializes in high-performance timing, memory interface, and RF power solutions for communications and computing markets.

The IDT70V639S product line was engineered for deterministic, low-latency inter-processor communication in real-time embedded systems-emphasizing hardware arbitration, flexible voltage interfaces, and seamless memory expansion.

FAQ

What is the maximum operating temperature range for the 70V639S12BCI8?

The 70V639S12BCI8 is rated for industrial temperature operation from −40°C to +85°C. This specification is validated across all electrical parameters including access time (12 ns max), standby current (ISB3 ≤6 mA), and BUSY arbitration timing (tBDD ≤12 ns), making it suitable for deployment in base stations, motor drives, and automotive ECUs.

Does the 70V639S12BCI8 support JTAG boundary scan?

No, the 70V639S12BCI8 does not support JTAG boundary scan. The PK128 TQFP package lacks sufficient pins to implement IEEE 1149.1 compliance, as explicitly stated in the datasheet: "Due to limited pin count, JTAG is not supported on the 128-pin TQFP package." Debug and test must rely on functional I/O verification.

How does the M/S pin affect BUSY signal behavior in the 70V639S12BCI8?

When M/S = VIH, the 70V639S12BCI8 operates as a Master and asserts BUSY as an output flag to block conflicting writes on the opposite port. When M/S = VIL, it acts as a Slave and accepts BUSY as an input signal-halting its own write cycle until BUSY goes high. This dual-role capability enables flexible master/slave memory configurations without external logic.

Can the left and right ports of the 70V639S12BCI8 operate at different I/O voltages?

Yes, the left and right ports of the 70V639S12BCI8 can operate at different I/O voltages. OPTL selects 3.3 V (VIH) or 2.5 V (VIL) for the left port's I/Os and controls, requiring VDDQL to match; OPTR performs the same function independently for the right port and VDDQR. This enables mixed-voltage system integration-for example, interfacing a 2.5 V FPGA with a 3.3 V microcontroller.

What memory address ranges trigger the INTL and INTR interrupt flags in the 70V639S12BCI8?

The 70V639S12BCI8 uses fixed addresses to control interrupts: writing to address 0x1FFFE sets the INTL flag (left port), while writing to 0x1FFFF sets the INTR flag (right port). Conversely, writing to 0x1FFFE with R/WL=VIH resets INTL, and writing to 0x1FFFF with R/WR=VIH resets INTR. These addresses are hardwired and do not depend on external decoding logic.

70V639S12BCI8 Specifications

Product attributes: Attribute value

Manufacturer:: Renesas

Series:: -

Package/Case:: 256-LBGA

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Programmable:: Not Verified

Memory Type:: Volatile

Memory Format:: SRAM

Technology:: SRAM - Dual Port, Asynchronous

Memory Size:: 2.25Mbit

Memory Organization:: 128K x 18

Memory Interface:: Parallel

Clock Frequency:: -

Write Cycle Time - Word, Page:: 12ns

Access Time:: 12 ns

Voltage - Supply:: 3.15V ~ 3.45V

Operating Temperature:: -40°C ~ 85°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 256-CABGA (17x17)

70V639S12BCI8 FAQ

1.How can I place an order for 70V639S12BCI8 through Aetrix?

Please submit a Request for Quotation (RFQ) for 70V639S12BCI8 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for 70V639S12BCI8 reliable?

The price and inventory of 70V639S12BCI8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 70V639S12BCI8 is usually 5 days.

3.What payment methods are accepted for 70V639S12BCI8?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 70V639S12BCI8 transactions.

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4.How is shipping managed for 70V639S12BCI8?

70V639S12BCI8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 70V639S12BCI8 order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for 70V639S12BCI8?

For technical support, including 70V639S12BCI8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 70V639S12BCI8 requirements.

6.How does Aetrix verify that 70V639S12BCI8 is sourced from the original manufacturer or authorized distributors?

All 70V639S12BCI8 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that 70V639S12BCI8 meets industry standards.

7.What is the process for return or replacement of 70V639S12BCI8?

All 70V639S12BCI8 units undergo pre-shipment inspection (PSI). If there is an issue with 70V639S12BCI8, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The 70V639S12BCI8 part is unused and in its original packaging.

Return procedure for 70V639S12BCI8:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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