My Inquiry
My Account
Renesas 71V321L55JI
- Part No.:
- 71V321L55JI
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 52-LCC (J-Lead)
- Datasheet:
-
71V321L55JI.pdf
- Description:
- IC SRAM 16KBIT PARALLEL 52PLCC
- Quantity:
- Payment:
- Shipping:
Inventory:3,655
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
71V321L55JI from Renesas Electronics (formerly IDT) is a high-speed, 3.3V, 2K × 8 dual-port static RAM with on-chip interrupt logic and BUSY arbitration for interprocessor communication. It supports fully asynchronous access from independent left/right ports, delivers 55 ns read/write cycle time, consumes ≤5 mA standby current (ISB3), and operates across –40°C to +85°C industrial temperature range - used in real-time embedded control systems requiring concurrent memory access.
For engineers reviewing the 71V321L55JI datasheet, 71V321L55JI pinout, 71V321L55JI application, or 71V321L55JI equivalent, key selection criteria include dual-port arbitration timing (tBDD ≤ 45 ns), battery-backed data retention at 2.0 V (VDR), TTL-compatible 3.3 V I/O, and PLCC-52 package compatibility with legacy board layouts.
Technical Context
This device implements true dual-port SRAM architecture with separate address, control, and bidirectional I/O buses per port - enabling simultaneous read/write operations without software coordination. Its hardware BUSY arbitration resolves port contention via address and chip-enable matching, asserting BUSYL/BUSYR outputs to stall conflicting accesses.
The interrupt subsystem uses dedicated mailbox addresses (7FEh for INTL, 7FFh for INTR) to signal cross-port events; flags are set by write operations and cleared by read accesses to those locations. All control signals (CEL/CER, OEL/OER, R/WL/R/WR) operate asynchronously with no internal clock required.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Organization | 2K × 8 bits (16,384 bits total); enables byte-wide parallel data exchange between two processors or subsystems. |
| Access Time (tAA) | 55 ns max - defines minimum address hold time before valid data appears; critical for meeting real-time latency budgets in control loops. |
| Read Cycle Time (tRC) | 55 ns max - determines maximum sustained read throughput (≈18.2 MHz) when alternating addresses. |
| Standby Current (ISB3) | 0.2 mA typ. at 3.3 V - achieved when both ports are fully deselected with CMOS-level inputs; enables ultra-low-power sleep modes. |
| Data Retention Voltage (VDR) | 2.0 V min - allows memory state preservation during main power loss using backup battery; verified for industrial temp range. |
| Operating Temperature | –40°C to +85°C - qualified for deployment in automotive engine control units, industrial PLCs, and telecom line cards. |
| Supply Voltage | 3.0 V to 3.6 V - single-rail operation simplifies power design; rejects supply noise up to ±0.3 V tolerance. |
Pinout & Package
71V321L55JI is packaged in a 52-pin Plastic Leaded Chip Carrier (PLCC), JEDEC standard PLG52 footprint (approx. 19.05 mm × 19.05 mm × 4.32 mm), with gull-wing leads and internal heat slug. Pin 1 marked by corner notch; requires full VCC and GND decoupling per datasheet layout guidelines.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0L–A10L | Left port address inputs | 11-bit address bus selecting one of 2K locations; must be stable before CE/OE assertion for reliable access. |
| I/O0L–I/O7L | Left port bidirectional data | 8-bit parallel data path; high-impedance when OEL = VIH or CEL = VIH; drives full TTL levels. |
| CEL, OEL, R/WL | Left port control enables | Chip enable (active low), output enable (active low), and read/write direction (high=read, low=write). |
| BUSYL, INTL | Left port status outputs | BUSYL indicates port contention (totem-pole, no pull-up needed); INTL is interrupt flag set by right-port writes to 7FEh. |
| A0R–A10R | Right port address inputs | Mirrored left-port addressing; independent timing allows concurrent access to different memory locations. |
| I/O0R–I/O7R | Right port bidirectional data | Electrically isolated from left I/O; supports independent data transfers without bus contention. |
| CER, OER, R/WR | Right port control enables | Functionally identical to left-side controls but with independent timing domains and arbitration interaction. |
| BUSYR, INTR | Right port status outputs | BUSYR signals contention from left port; INTR asserted when left port writes to 7FFh mailbox address. |
Key Features
| Feature | Design Value |
|---|---|
| Dual-port arbitration with BUSY outputs | Hardware-resolved contention detection via address/CE match; eliminates need for external semaphores or polling in multi-CPU designs. |
| Interprocessor interrupt mailboxes | Dedicated 7FEh (INTL) and 7FFh (INTR) addresses enable zero-latency event signaling between ports without shared registers or software overhead. |
| 2.0 V data retention mode | Preserves memory contents during main power failure using backup battery; validated down to –40°C, supporting fail-safe system recovery. |
| TTL-compatible 3.3 V interface | Direct connection to 3.3 V microcontrollers and FPGAs without level-shifting; VIH = 2.0 V min ensures robust noise margin in noisy environments. |
| Low-power standby (ISB3 = 0.2 mA) | Enables energy-efficient operation in battery-powered or thermally constrained applications; reduces thermal load and extends system runtime. |
Applications
| Industrial Motion Controller | Telecom Line Card |
|---|---|
|
Use Scenario: Two DSPs coordinate motor trajectory calculation and real-time PWM update via shared memory. IC Role / Device Role / Timing Role: 71V321L55JI serves as synchronized data exchange buffer with hardware arbitration preventing write collisions during simultaneous updates. Use Value: Eliminates software semaphore delays; 55 ns access ensures sub-microsecond response to encoder feedback changes. |
Use Scenario: Host processor and packet-processing ASIC share configuration tables and statistics counters in carrier-grade Ethernet switch. IC Role / Device Role / Timing Role: 71V321L55JI acts as dual-access scratchpad memory with interrupt-driven notification of new frame descriptors. Use Value: Reduces inter-ASIC latency by >3× vs. serial bus handshaking; BUSY logic prevents corruption during burst descriptor writes. |
| Automotive Engine Control Unit | Medical Imaging Subsystem |
|
Use Scenario: Safety-critical MCU and diagnostics co-processor exchange sensor logs and fault codes while maintaining ASIL-B compliance. IC Role / Device Role / Timing Role: 71V321L55JI provides fault-tolerant memory partitioning with battery-backed retention for crash-data capture. Use Value: Guarantees post-incident data integrity even after main power loss; 2.0 V retention meets ISO 16750-2 pulse test requirements. |
Use Scenario: FPGA-based image acquisition module and ARM host CPU transfer raw pixel buffers and metadata in ultrasound scanner. IC Role / Device Role / Timing Role: 71V321L55JI functions as high-bandwidth frame buffer with mailbox interrupts synchronizing DMA transfers. Use Value: Enables continuous 120 fps imaging without CPU polling; 8-bit parallel interface sustains >17 MB/s throughput. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-port SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CY7C024AV-55AXC | 55 ns access, 2K × 16 organization, 3.3 V core, but requires external BUSY arbitration logic and lacks integrated interrupt mailboxes. | Suitable for wider data paths; not drop-in for 8-bit systems requiring mailbox-based IPC. | Select when 16-bit bus width is mandatory and external arbitration is acceptable. |
| AS7C3256B-55JC | 55 ns, 32K × 8, 3.3 V, no BUSY or interrupt logic; single-port architecture with optional dual-port variants requiring external glue logic. | Higher density but no hardware interprocessor signaling; requires firmware-managed semaphores. | Choose for cost-sensitive, non-real-time applications where software coordination suffices. |
Compared with CY7C024AV-55AXC and AS7C3256B-55JC, the 71V321L55JI uniquely integrates hardware arbitration and mailbox interrupts in an 8-bit dual-port package - reducing BOM count, PCB area, and firmware complexity for tightly coupled multi-processor systems.
Availability
71V321L55JI is available at Aetrix Electronics and suitable for industrial motion controllers, telecom line cards, and automotive engine control units requiring stable component supply and long-term lifecycle support.
Supply support for 71V321L55JI 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
Renesas Electronics Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for automotive, industrial, and infrastructure markets.
The 71V321L series belongs to Renesas' legacy dual-port SRAM portfolio, designed specifically for deterministic interprocessor communication in real-time embedded systems where hardware arbitration and low-latency mailbox signaling are essential.
FAQ
What is the maximum operating temperature range for the 71V321L55JI?
The 71V321L55JI is rated for industrial temperature operation from –40°C to +85°C, as confirmed in the "Recommended Operating Temperature and Supply Voltage" table (page 3) and ordering information (page 14). This qualification supports deployment in under-hood automotive ECUs and factory-floor PLCs where ambient thermal stress exceeds commercial-grade limits.
Does the 71V321L55JI support battery backup for data retention?
Yes, the 71V321L55JI supports data retention at 2.0 V minimum supply voltage (VDR), with typical retention current of 100 µA at 2 V and 25°C. This capability is exclusive to the "L" (low-power) variant and is documented in Table 7 (Data Retention Characteristics) and Figure 4 (Data Retention Waveform) of the datasheet.
How does the BUSY arbitration logic function in the 71V321L55JI?
The 71V321L55JI asserts BUSYL or BUSYR when both ports attempt access to the same memory location simultaneously - determined solely by address and chip-enable matching. The winning port proceeds; the losing port's write is gated internally. Timing parameters like tBDD (≤45 ns) define delay from BUSY deassertion to valid data, ensuring deterministic resolution without software intervention.
What package type is used for the 71V321L55JI?
The 71V321L55JI uses a 52-pin Plastic Leaded Chip Carrier (PLCC) package, identified as PLG52 in Renesas' ordering nomenclature. Pin configuration diagrams (page 2) and mechanical dimensions (note 3, page 2) confirm its 19.05 mm × 19.05 mm body size with gull-wing leads compatible with standard PLCC sockets and reflow profiles.
Can the 71V321L55JI be used in a 3.0 V system?
Yes, the 71V321L55JI operates across a 3.0 V to 3.6 V supply range, as specified in the "Recommended DC Operating Conditions" table (page 3). At 3.0 V, all AC timing parameters (e.g., tRC = 55 ns max) and DC characteristics (e.g., VOH ≥ 2.4 V) remain guaranteed, enabling interoperability with 3.0 V logic families without level shifters.
71V321L55JI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 52-LCC (J-Lead)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Volatile
- Memory Format:
- SRAM
- Technology:
- SRAM - Dual Port, Asynchronous
- Memory Size:
- 16Kbit
- Memory Organization:
- 2K x 8
- Memory Interface:
- Parallel
- Clock Frequency:
- -
- Write Cycle Time - Word, Page:
- 55ns
- Access Time:
- 55 ns
- Voltage - Supply:
- 3V ~ 3.6V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 52-PLCC (19.13x19.13)
71V321L55JI FAQ
1.How can I place an order for 71V321L55JI through Aetrix?
Please submit a Request for Quotation (RFQ) for 71V321L55JI 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 71V321L55JI reliable?
The price and inventory of 71V321L55JI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 71V321L55JI is usually 5 days.
3.What payment methods are accepted for 71V321L55JI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 71V321L55JI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 71V321L55JI?
71V321L55JI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 71V321L55JI 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 71V321L55JI?
For technical support, including 71V321L55JI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 71V321L55JI requirements.
6.How does Aetrix verify that 71V321L55JI is sourced from the original manufacturer or authorized distributors?
All 71V321L55JI 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 71V321L55JI meets industry standards.
7.What is the process for return or replacement of 71V321L55JI?
All 71V321L55JI units undergo pre-shipment inspection (PSI). If there is an issue with 71V321L55JI, 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 71V321L55JI part is unused and in its original packaging.
Return procedure for 71V321L55JI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
71V321L55JI Tags
-
M24C02-WMN6TP
STMicroelectronics
-
AT24C02C-XHM-T
Microchip Technology
-
AT21CS01-STUM10-T
Microchip Technology
-
AT24C02C-SSHM-T
Microchip Technology
-
24LC01BT-I/OT
Microchip Technology
-
M24C02-FMC6TG
STMicroelectronics
-
AT24CS02-SSHM-T
Microchip Technology
-
93LC46BT-I/OT
Microchip Technology
-
AT24C04C-SSHM-T
Microchip Technology
-
24LC01BT-I/SN
Microchip Technology
-
24AA02UIDT-I/OT
Microchip Technology
-
AT24C08C-STUM-T
Microchip Technology
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
