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Renesas 71321SA55TFI
- Part No.:
- 71321SA55TFI
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 64-LQFP
- Datasheet:
-
71321SA55TFI.pdf
- Description:
- IC SRAM 16KBIT PARALLEL 64TQFP
- Quantity:
- Payment:
- Shipping:
Inventory:4,640
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Product details
Overview
IDT71321SA55TFI from Integrated Device Technology is a high-speed 2K × 8 dual-port static RAM with interrupt logic and on-chip arbitration, designed as a MASTER device for interprocessor communication. It delivers 55 ns max read/write cycle time, operates at 5 V ±10%, supports industrial temperature (–40°C to +85°C), and features open-drain BUSY/INT outputs requiring 270 Ω pull-up resistors - used in real-time embedded control systems requiring concurrent memory access.
For engineers reviewing the IDT71321SA55TFI datasheet, IDT71321SA55TFI pinout, IDT71321SA55TFI application, or IDT71321SA55TFI equivalent, key selection criteria include dual-port arbitration timing (tBAA ≤ 30 ns), interrupt mailbox addressing (7FEH/7FFH), BUSY output behavior, 64-pin TQFP package compatibility, and LA/SA power variant differentiation.
Technical Context
The IDT71321SA55TFI implements fully asynchronous dual-port operation with independent left/right address, control, and I/O buses. Its on-chip arbitration logic resolves port contention via BUSY flag generation based on chip enable (CEL/CER) and address match detection - not R/W state - ensuring deterministic write inhibition during simultaneous access to identical addresses.
Interrupt functionality uses dedicated mailbox addresses (7FEH for INTL, 7FFH for INTR) with edge-triggered flag assertion on write and level-sensitive clearing on read. The device requires external 270 Ω pull-up resistors on BUSY/INT pins and supports battery backup data retention only in LA variants - not applicable to this SA-grade part.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 2K × 8 bits (2048 words × 8-bit wide), enabling compact shared-memory buffers between two processors |
| Access Time | 55 ns max (tAA, tACE, tAOE), defining worst-case latency for deterministic real-time response |
| Supply Voltage | 5.0 V ±10% (4.5–5.5 V), compatible with legacy TTL-level system rails without regulation overhead |
| Operating Temp | –40°C to +85°C industrial grade, qualifying for deployment in motor drives and industrial PLCs |
| Standby Current | 20 mA max (ISB1, SA variant), enabling low-power idle states during inter-processor handshaking |
| Interrupt Latency | tINS ≤ 45 ns (max), guaranteeing sub-50 ns notification of cross-port mailbox writes |
| BUSY Timing | tBAA ≤ 30 ns (BUSY access from address), critical for synchronizing arbitration in master/slave width-expansion configurations |
Pinout & Package
Package: 64-pin TQFP (PNG64), 14 mm × 14 mm × 1.4 mm body, lead-free and RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0L–A10L | Left port address inputs | 11-bit address bus for left-side memory access (000H–7FFH) |
| A0R–A10R | Right port address inputs | 11-bit address bus for right-side memory access (000H–7FFH) |
| I/O0L–I/O7L | Left port bidirectional data | 8-bit data path; high-impedance when OEL = VIH or CEL = VIH |
| I/O0R–I/O7R | Right port bidirectional data | 8-bit data path; high-impedance when OER = VIH or CER = VIH |
| CEL / CER | Chip enable (left/right) | Active-low enables respective port; controls power-down mode (ISB1/ISB2) |
| OEL / OER | Output enable (left/right) | Active-low enables I/O drivers; overrides R/W for tristate control |
| R/WL / R/WR | Read/write control (left/right) | High = read, low = write; determines direction when OE active |
| INTL / INTR | Interrupt flags (left/right) | Open-drain outputs; require 270 Ω pull-up; assert on mailbox writes (7FEH/7FFH) |
| BUSYL / BUSYR | BUSY flags (left/right) | Open-drain outputs (MASTER); require 270 Ω pull-up; indicate port contention |
| VCC / GND | Power supply | All VCC pins must be connected to 5 V; all GND pins tied to common ground plane |
Key Features
| Feature | Design Value |
|---|---|
| On-chip arbitration logic | Resolves simultaneous access conflicts without external logic by asserting BUSY on contested addresses |
| Dual interrupt mailboxes | Hardware-accelerated interprocessor signaling via dedicated 7FEH (INTL) and 7FFH (INTR) SRAM locations |
| Asynchronous dual-port operation | Enables independent, unsynchronized reads/writes from either port - no clock required |
| 55 ns industrial-grade timing | Guaranteed performance across –40°C to +85°C, supporting deterministic latency in motion control |
| Low standby power (SA variant) | 20 mA max ISB1 current allows energy-efficient idle states during inter-processor synchronization |
Applications
| Motor Control System | Industrial PLC |
|---|---|
Use Scenario: Two microcontrollers coordinate real-time PWM updates and feedback sampling using shared memory. IC Role / Device Role / Timing Role: IDT71321SA55TFI acts as MASTER dual-port RAM, arbitrating concurrent access to torque/position registers while signaling status changes via INTL/INTR. Use Value: Eliminates software polling and reduces inter-processor latency to ≤45 ns interrupt assertion, improving closed-loop responsiveness. | Use Scenario: A main CPU and I/O processor exchange configuration data and sensor readings in an isolated control cabinet. IC Role / Device Role / Timing Role: IDT71321SA55TFI provides non-blocking memory access with hardware BUSY arbitration, preventing data corruption during simultaneous register updates. Use Value: Guarantees atomic write operations under contention via tBAA ≤ 30 ns BUSY assertion, enabling reliable deterministic I/O scanning. |
| Avionics Data Logger | Medical Imaging Subsystem |
Use Scenario: Flight data acquisition unit and safety monitor share telemetry buffers with strict timing isolation. IC Role / Device Role / Timing Role: IDT71321SA55TFI serves as MASTER in a dual-processor architecture, using 7FEH/7FFH mailboxes for priority event signaling. Use Value: Delivers ≤55 ns access time and industrial temp rating, meeting DO-254 functional safety timing constraints for airborne systems. | Use Scenario: Image processing FPGA and host ARM processor exchange frame metadata and calibration tables. IC Role / Device Role / Timing Role: IDT71321SA55TFI enables zero-wait-state memory sharing between heterogeneous processors with independent clocks. Use Value: Asynchronous operation removes clock domain crossing logic, simplifying HDL design and reducing FPGA resource usage. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-port SRAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Cypress CY7C136-55JC | 55 ns access, 2K × 8, but lacks integrated BUSY arbitration and interrupt logic; requires external glue logic for contention handling | Suitable for simpler dual-CPU systems without strict real-time arbitration needs | Select when cost sensitivity outweighs need for hardware arbitration and mailbox interrupts |
| ISSI IS61LV25616AL-10TLI | 10 ns faster (45 ns), but single-port only; no native dual-port interface or BUSY/INT signals | Requires external dual-port controller IC or FPGA logic to emulate dual-port behavior | Select only if system already includes a dual-port bridge or can absorb added complexity and latency |
Compared with CY7C136-55JC and IS61LV25616AL-10TLI, the IDT71321SA55TFI uniquely integrates arbitration and interrupt logic in silicon - eliminating external components, reducing PCB area, and guaranteeing sub-50 ns interprocessor signaling without firmware overhead.
Availability
IDT71321SA55TFI is available at Aetrix Electronics and suitable for motor control systems, industrial PLCs, avionics data loggers, and medical imaging subsystems requiring stable component supply and guaranteed industrial-temperature performance.
Supply support for IDT71321SA55TFI 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, designs high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.
IDT71321SA55TFI belongs to the IDT71321/71421 dual-port SRAM family, engineered specifically for deterministic interprocessor communication in real-time embedded systems where hardware arbitration and low-latency interrupts are critical.
FAQ
What is the maximum operating temperature range for IDT71321SA55TFI?
IDT71321SA55TFI is rated for industrial temperature operation from –40°C to +85°C, validated across all electrical parameters including 55 ns access time, BUSY arbitration timing, and interrupt latency. This specification is guaranteed per the official IDT datasheet DSC-2691/17 and applies to the SA speed grade in 64-pin TQFP packaging.
Does IDT71321SA55TFI support battery backup data retention?
No, IDT71321SA55TFI does not support battery backup data retention. That feature is exclusive to LA variants (e.g., IDT71321LA55TFI), which specify 2 V data retention capability. The "SA" suffix denotes standard power operation only, with full 5 V supply required for active and standby modes.
How is BUSY signal behavior different between IDT71321SA55TFI and IDT71421SA55TFI?
IDT71321SA55TFI functions as the MASTER device: BUSYL and BUSYR are open-drain outputs requiring 270 Ω pull-up resistors and assert LOW during port contention. In contrast, IDT71421SA55TFI (SLAVE) has BUSYL/BUSYR as inputs that internally inhibit writes when driven LOW - confirming the MASTER/SLAVE pairing requirement for width expansion.
What are the valid interrupt mailbox addresses for IDT71321SA55TFI?
IDT71321SA55TFI uses fixed interrupt mailbox addresses: writing to 7FEH (hex) on the right port asserts INTL, and writing to 7FFH (hex) on the left port asserts INTR. These locations are user-accessible SRAM cells - the written data becomes the message payload, and reading the same address clears the corresponding flag.
Is IDT71321SA55TFI pin-compatible with other speed grades in the same package?
Yes, IDT71321SA55TFI is pin-compatible with other IDT71321XxxTFI variants (e.g., IDT71321SA25TFI, IDT71321SA35TFI) in the 64-pin TQFP (PNG64) package. All share identical pinout, voltage, and interface specifications - only access timing parameters differ, allowing drop-in replacement where timing margins permit.
71321SA55TFI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 64-LQFP
- Packaging:
- Tray
- 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:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 64-TQFP (10x10)
71321SA55TFI FAQ
1.How can I place an order for 71321SA55TFI through Aetrix?
Please submit a Request for Quotation (RFQ) for 71321SA55TFI 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 71321SA55TFI reliable?
The price and inventory of 71321SA55TFI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 71321SA55TFI is usually 5 days.
3.What payment methods are accepted for 71321SA55TFI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 71321SA55TFI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 71321SA55TFI?
71321SA55TFI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 71321SA55TFI 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 71321SA55TFI?
For technical support, including 71321SA55TFI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 71321SA55TFI requirements.
6.How does Aetrix verify that 71321SA55TFI is sourced from the original manufacturer or authorized distributors?
All 71321SA55TFI 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 71321SA55TFI meets industry standards.
7.What is the process for return or replacement of 71321SA55TFI?
All 71321SA55TFI units undergo pre-shipment inspection (PSI). If there is an issue with 71321SA55TFI, 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 71321SA55TFI part is unused and in its original packaging.
Return procedure for 71321SA55TFI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
71321SA55TFI Tags
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AT24C02C-XHM-T
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AT21CS01-STUM10-T
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