My Inquiry
My Account
Renesas 71321LA20TF
- Part No.:
- 71321LA20TF
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 64-LQFP
- Datasheet:
-
71321LA20TF.pdf
- Description:
- IC SRAM 16KBIT PARALLEL 64TQFP
- Quantity:
- Payment:
- Shipping:
Inventory:3,332
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
IDT71321LA20TF from Integrated Device Technology is a high-speed 2K × 8 dual-port static RAM with interrupt and BUSY arbitration logic, designed as a MASTER device for interprocessor communication systems. It delivers 20 ns max read cycle time, 2V data retention in battery backup mode, industrial temperature operation (–40°C to +85°C), and supports fully asynchronous dual-port access. It is used in real-time embedded control systems requiring concurrent memory access by two independent processors.
For engineers reviewing the IDT71321LA20TF datasheet, IDT71321LA20TF pinout, IDT71321LA20TF application, or IDT71321LA20TF equivalent, key selection criteria include its MASTER arbitration capability, 2V data retention, 52-pin STQFP package, and compatibility with IDT71421SLAVE devices in 16-bit+ memory expansions.
Technical Context
The IDT71321LA20TF implements on-chip port arbitration logic that resolves contention when both ports access the same address simultaneously - asserting BUSYL/BUSYR outputs to inhibit writes on the losing port. Its interrupt logic uses dedicated mailbox addresses (7FEH for INTL, 7FFH for INTR) to signal cross-port events without software polling.
It operates with TTL-compatible 5V ±10% supply, features open-drain BUSY/INT outputs requiring 270Ω pull-ups, and supports full standby current as low as 0.2 mA (typ.) under CMOS-level inputs. The LA variant enables battery backup with 2V data retention and 100–1500 µA retention current.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 2K × 8 = 16,384 bits; sufficient for small real-time buffers or dual-processor shared workspaces. |
| Access Time | 20 ns (max); enables direct interfacing with 40–50 MHz microcontrollers without wait states. |
| Data Retention | 2 V minimum; allows backup from coin-cell batteries during main power loss in industrial systems. |
| Operating Temp | –40°C to +85°C; qualified for industrial control, motor drives, and transportation electronics. |
| Supply Voltage | 4.5–5.5 V; compatible with standard 5V logic rails and tolerant of line regulation variation. |
| Standby Current | 0.2 mA (typ.) at full CMOS standby; reduces system power budget in sleep-mode applications. |
| Package | 52-pin STQFP (PPG52); 10 mm × 10 mm footprint with gull-wing leads for automated assembly. |
Pinout & Package
Package: 52-pin STQFP (PPG52), 10 mm × 10 mm × 1.4 mm body, gull-wing lead form, RoHS-compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0L–A10L | Left port address inputs | 11-bit address bus for left-side processor; accesses full 2K space (000–7FFH). |
| A0R–A10R | Right port address inputs | Independent 11-bit address bus for right-side processor; fully asynchronous with left port. |
| I/O0L–I/O7L | Left port bidirectional data | 8-bit parallel I/O; high-impedance when OEL = VIH or CEL = VIH. |
| I/O0R–I/O7R | Right port bidirectional data | 8-bit parallel I/O; electrically isolated from left port I/O lines. |
| CEL / CER | Chip enable (left/right) | Active-low enables respective port; controls power-down mode and arbitration timing. |
| OEL / OER | Output enable (left/right) | Active-low enables data drivers; separates read/write control from chip select. |
| R/WL / R/WR | Read/write control (left/right) | Active-low write; high = read; determines direction of I/O bus traffic per port. |
| BUSYL / BUSYR | BUSY flag (output only) | Open-drain outputs indicating port arbitration loss; require external 270Ω pull-up to VCC. |
| INTL / INTR | Interrupt flags (output) | Open-drain outputs signaling mailbox writes (7FEH/7FFH); also require 270Ω pull-up. |
| VCC / GND | Power supply pins | Multiple VCC (pins 18, 27, 40, 47) and GND (pins 21, 33, 45, 52) ensure low-noise decoupling. |
Key Features
| Feature | Design Value |
|---|---|
| On-chip arbitration logic | Resolves simultaneous same-address access without external logic; guarantees deterministic BUSY assertion. |
| Dual interrupt mailboxes | Hardware-triggered INTL/INTR via dedicated SRAM locations (7FEH, 7FFH) eliminates polling overhead. |
| 2V data retention | Preserves memory contents during main power failure using low-voltage battery backup (LA variant only). |
| Master-only BUSY output | BUSYL/BUSYR are outputs only on IDT71321LA20TF - enables use as master in MASTER/SLAVE configurations. |
| Asynchronous dual-port operation | Independent control/address/I/O per port allows true concurrent read/write across processors with no clock synchronization. |
Applications
| Industrial PLC Communication Buffer | Real-Time Motor Control Co-Processor Interface |
|---|---|
|
Use Scenario: Two microcontrollers - one handling HMI and diagnostics, the other managing servo loop execution - share status, command, and error data in real time. IC Role / Device Role / Timing Role: IDT71321LA20TF acts as MASTER dual-port RAM, providing atomic mailbox exchange and BUSY-controlled write coordination between cores. Use Value: Eliminates software semaphores and reduces inter-core latency to sub-20 ns, enabling deterministic response in <100 µs motion control cycles. |
Use Scenario: A safety-critical motor drive uses separate safety MCU and motion MCU; both must access shared torque limits, fault logs, and calibration tables. IC Role / Device Role / Timing Role: IDT71321LA20TF serves as fault-tolerant shared memory with hardware arbitration, preventing corrupted writes during simultaneous access. Use Value: Ensures data integrity without CPU intervention; 2V retention preserves last-fault state across power loss for post-mortem analysis. |
| Avionics Data Concentrator Interface | Medical Imaging Real-Time Frame Buffer |
|
Use Scenario: ARINC 429 receiver and flight management system (FMS) processor concurrently log and process sensor telemetry in airborne systems. IC Role / Device Role / Timing Role: IDT71321LA20TF functions as MASTER buffer with interrupt-driven notification, allowing FMS to respond immediately to new packet arrival. Use Value: Reduces interrupt latency to ≤25 ns (tINS), meeting DO-254 deterministic timing requirements for Level A avionics. |
Use Scenario: CT scanner front-end FPGA acquires raw projection data while host ARM processor reconstructs images - both access overlapping frame buffers. IC Role / Device Role / Timing Role: IDT71321LA20TF provides zero-wait-state dual-port access to 16 KB buffer space, synchronized via BUSY arbitration. Use Value: Enables continuous acquisition at >100 MB/s sustained throughput without pipeline stalls or external FIFO buffering. |
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 CY7C024AV-20AXC | 2K × 16 organization; 20 ns access; no built-in BUSY arbitration; requires external logic for contention resolution. | Best suited for simpler dual-CPU systems where arbitration is handled in firmware or external CPLD. | Select when wider data bus (16-bit) is required and arbitration complexity can be managed externally. |
| ISSI IS61LV25616AL-20TQLI | 256K × 16 sync SRAM; 20 ns; synchronous interface only; no dual-port or interrupt logic. | Requires clocked interface and external arbitration; not drop-in compatible for asynchronous dual-access use cases. | Choose only if migrating to synchronous architecture and redesigning control logic is acceptable. |
Compared with CY7C024AV-20AXC and IS61LV25616AL-20TQLI, the IDT71321LA20TF uniquely integrates hardware arbitration and interrupt mailboxes in an asynchronous 2K × 8 format - eliminating external logic, reducing BOM count, and guaranteeing deterministic timing in real-time interprocessor communication.
Availability
IDT71321LA20TF is available at Aetrix Electronics and suitable for industrial PLCs, avionics data concentrators, and medical imaging subsystems requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.
Supply support for IDT71321LA20TF 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, is a fabless semiconductor company specializing in timing, memory interface, and RF power solutions for high-performance computing and industrial systems.
The IDT71321LA series was designed specifically for deterministic interprocessor communication in real-time embedded systems - emphasizing hardware arbitration, low-latency interrupts, and battery-backed data retention for mission-critical applications.
FAQ
What is the function of BUSYL and BUSYR on the IDT71321LA20TF?
BUSYL and BUSYR are open-drain output signals indicating arbitration loss on the left or right port, respectively. When both ports attempt to write to the same address, the IDT71321LA20TF asserts the losing port's BUSY signal to inhibit the write. These outputs require external 270Ω pull-up resistors to VCC and are used exclusively in MASTER configuration - unlike SLAVE devices where BUSY is an input.
Does the IDT71321LA20TF support battery backup operation?
Yes, the IDT71321LA20TF supports battery backup with guaranteed data retention at VCC ≥ 2.0 V. In retention mode, it draws as little as 100 µA (typ.) at +25°C, enabling operation from standard coin-cell batteries during main power loss. This feature is exclusive to LA variants and is not available in SA versions.
How does interrupt functionality work in the IDT71321LA20TF?
The IDT71321LA20TF uses dedicated SRAM addresses 7FEH (for INTL) and 7FFH (for INTR) as hardware mailboxes. Writing to 7FFH from the left port asserts INTR; reading 7FFH from the right port clears it. Similarly, 7FEH controls INTL. Both flags are open-drain outputs requiring 270Ω pull-ups and provide zero-software-overhead interprocessor signaling.
Can the IDT71321LA20TF be used as a SLAVE device in MASTER/SLAVE configurations?
No - the IDT71321LA20TF is strictly a MASTER device. Its BUSYL and BUSYR pins are outputs only, and it contains on-chip arbitration logic required for MASTER operation. To build a 16-bit or wider dual-port memory, pair IDT71321LA20TF with IDT71421SLAVE devices, where BUSY becomes an input used to inhibit writes.
What package type is used for the IDT71321LA20TF?
The IDT71321LA20TF is packaged in a 52-pin STQFP (Surface-Mount Thin Quad Flat Package), also designated PPG52. It measures 10 mm × 10 mm × 1.4 mm with gull-wing leads, optimized for automated SMT assembly and thermal performance in industrial environments.
71321LA20TF 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:
- 20ns
- Access Time:
- 20 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 64-TQFP (10x10)
71321LA20TF FAQ
1.How can I place an order for 71321LA20TF through Aetrix?
Please submit a Request for Quotation (RFQ) for 71321LA20TF 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 71321LA20TF reliable?
The price and inventory of 71321LA20TF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 71321LA20TF is usually 5 days.
3.What payment methods are accepted for 71321LA20TF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 71321LA20TF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 71321LA20TF?
71321LA20TF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 71321LA20TF 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 71321LA20TF?
For technical support, including 71321LA20TF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 71321LA20TF requirements.
6.How does Aetrix verify that 71321LA20TF is sourced from the original manufacturer or authorized distributors?
All 71321LA20TF 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 71321LA20TF meets industry standards.
7.What is the process for return or replacement of 71321LA20TF?
All 71321LA20TF units undergo pre-shipment inspection (PSI). If there is an issue with 71321LA20TF, 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 71321LA20TF part is unused and in its original packaging.
Return procedure for 71321LA20TF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
71321LA20TF 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…
