My Inquiry
My Account
Renesas IDT71256SA20YI8
- Part No.:
- IDT71256SA20YI8
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 28-BSOJ (0.300", 7.62mm Width)
- Datasheet:
-
IDT71256SA20YI8.pdf
- Description:
- IC SRAM 256KBIT PARALLEL 28SOJ
- Quantity:
- Payment:
- Shipping:
Inventory:2,562
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
IDT71256SA20YI8 from Renesas Electronics is a 32K × 8-bit (256 Kbit) high-speed CMOS static RAM with industrial temperature range (–40°C to +85°C), 20 ns access time, TTL-compatible I/O, single 5 V supply operation, and dual enable control (CS + OE). It serves as main or buffer memory in real-time embedded controllers requiring deterministic, no-refresh asynchronous access.
For engineers reviewing the IDT71256SA20YI8 datasheet, IDT71256SA20YI8 pinout, IDT71256SA20YI8 application, or IDT71256SA20YI8 equivalent, key selection criteria include industrial-grade timing consistency, low standby current (ISB1 = 15 mA), bidirectional TTL-level I/O compatibility, and SOJ-28 package suitability for legacy board space constraints.
Technical Context
The IDT71256SA20YI8 implements fully static asynchronous architecture-no clocks, no refresh cycles-enabling deterministic read/write latency across its full industrial temperature range. Its control logic supports both CS-controlled and WE-controlled write timing modes, with separate chip select (CS) and output enable (OE) pins enabling flexible bus arbitration and multi-device sharing.
It uses high-reliability CMOS process technology with verified input/output leakage ≤5 µA, VIH ≥2.2 V, VIL ≤0.8 V, and guaranteed tAA/tRC = 20 ns at VCC = 4.5–5.5 V. The device maintains valid data hold (tDH = 0 ns min) and fast output disable (tOHZ = 8 ns max) to support tight bus turnaround in microcontroller co-processor interfaces.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Organization | 32K × 8-bit (262,144-bit total); supports byte-wide parallel data transfers without multiplexing. |
| Access Time (tAA) | 20 ns max at VCC = 4.5–5.5 V; ensures predictable read latency in interrupt-driven firmware stacks. |
| Supply Voltage | 4.5 V to 5.5 V; compatible with standard 5 V TTL/CMOS system rails without regulation overhead. |
| Standby Current (ISB1) | 15 mA max at CMOS-level chip deselect (CS > VHC); enables low-power sleep modes in battery-backed systems. |
| I/O Compatibility | TTL-input and TTL-output levels (VIH ≥2.2 V, VOL ≤0.4 V @ 8 mA); interoperable with legacy 80Cxx, Z80, and 68K-family buses. |
| Operating Temperature | –40°C to +85°C; qualified for industrial automation, motor drives, and outdoor telecom equipment. |
| Package | 28-pin 300-mil Plastic SOJ (PJG28); footprint-compatible with JEDEC MS-012AB, suitable for wave-soldered legacy PCBs. |
Pinout & Package
Package: 28-pin 300-mil Plastic SOJ (PJG28), gull-wing lead form, body width 300 mil (7.62 mm), compliant with JEDEC MO-021AC.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A14 | Address Inputs | 15-bit address bus; selects one of 32,768 memory locations; latched on CS transition for stable decoding. |
| I/O0–I/O7 | Bidirectional Data Bus | 8-bit TTL-compatible data path; tri-stated when CS = high or OE = high; supports read/write without external transceivers. |
| CS | Chip Select | Active-low enable; places device in active (low) or ultra-low-power standby (high-Z, ISB1 = 15 mA) mode. |
| OE | Output Enable | Active-low control for output drivers only; allows CS to remain asserted during bus sharing while disabling outputs. |
| WE | Write Enable | Active-low write strobe; initiates write cycle when CS = low; defines tWP (15 ns min) and tDW (11 ns min) timing windows. |
| VCC, GND | Power Supply | Single 5 V supply; decoupling required per JEDEC guidelines due to 145 mA dynamic ICC at fMAX. |
Key Features
| Feature | Design Value |
|---|---|
| Fully static asynchronous operation | No clock, no refresh, no wait states-guarantees deterministic access within 20 ns across full temperature range. |
| Dual enable architecture (CS + OE) | Enables independent control of chip activation and output driver state-critical for shared-bus arbitration in multi-master systems. |
| TTL-compatible I/O interface | Direct connection to 5 V microcontrollers (e.g., Intel 80C188, Motorola 68EC000) without level-shifting circuitry. |
| Low ISB1 standby current | 15 mA at CMOS-level chip deselect supports energy-efficient sleep modes in programmable logic controllers (PLCs). |
| Industrial temperature qualification | Validated operation from –40°C to +85°C per AEC-Q100 Class 2-equivalent stress testing-suitable for under-hood or factory-floor use. |
Applications
| Industrial PLC Memory Buffer | Legacy Microcontroller System RAM |
|---|---|
|
Use Scenario: Real-time I/O scanning and ladder logic execution in DIN-rail mounted programmable logic controllers. IC Role / Device Role / Timing Role: Non-volatile buffer memory holding process image data between scan cycles; accessed asynchronously by 8/16-bit MCUs. Use Value: 20 ns tAA ensures sub-100 µs scan cycle overhead; industrial temp rating eliminates derating in uncooled enclosures. |
Use Scenario: Main working RAM in retro-computing platforms or industrial HMIs based on Z80 or 8086 derivatives. IC Role / Device Role / Timing Role: Byte-addressable SRAM replacing slower DRAM+refresh circuits; interfaced via discrete glue logic. Use Value: TTL-compatible I/O and 28-pin SOJ footprint allow drop-in replacement of obsolete 62256 variants without PCB redesign. |
| Telecom Line Card Buffer | Motor Drive Controller Data Store |
|
Use Scenario: Packet buffering and status logging in E1/T1 line interface cards operating in temperature-variable central office environments. IC Role / Device Role / Timing Role: Dual-port accessible memory storing frame headers and error counters; accessed by DSP and host processor via time-multiplexed bus. Use Value: Separate CS/OE pins enable seamless bus handoff; ISB1 = 15 mA reduces thermal load in densely packed line cards. |
Use Scenario: Parameter storage and runtime variable retention in servo drive firmware executing position-loop PID calculations. IC Role / Device Role / Timing Role: Fast-access scratchpad memory for coefficient tables and encoder interpolation buffers. Use Value: 20 ns access time aligns with 50 MHz MCU bus cycles; industrial temp range ensures reliability near power-stage MOSFETs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar static RAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CY62256NLL-20ZSXI | 20 ns access, same 32K×8 organization, but uses 28-pin TSOP (SOIC-type) instead of SOJ; higher ICC (160 mA vs. 145 mA). | Requires PCB pad revision for TSOP footprint; better suited for reflow-assembled new designs than wave-soldered legacy boards. | Select when migrating to surface-mount assembly and higher-density layouts. |
| AS6C2016-20TIN | 20 ns access, 32K×8, 28-pin SOJ package identical to IDT71256SA20YI8, but rated only for commercial temp (0°C to +70°C). | Lacks industrial temperature qualification-unsuitable for deployments outside climate-controlled environments. | Select only for cost-sensitive commercial equipment where ambient temperature remains bounded. |
Compared with CY62256NLL-20ZSXI and AS6C2016-20TIN, the IDT71256SA20YI8 uniquely combines industrial temperature rating, SOJ-28 footprint, and 15 mA ISB1 standby current-making it the sole option for maintaining legacy industrial hardware without layout change or thermal compromise.
Availability
IDT71256SA20YI8 is available at Aetrix Electronics and suitable for industrial PLCs, legacy microcontroller systems, telecom line cards, and motor drive controllers requiring stable component supply across extended lifecycle programs.
Supply support for IDT71256SA20YI8 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 is a global semiconductor leader delivering trusted embedded solutions for automotive, industrial, infrastructure, and IoT applications, with deep heritage in memory and microcontroller technologies.
The IDT71256SA series originates from Integrated Device Technology (acquired by Renesas in 2019) and targets industrial and communications systems requiring high-reliability, no-refresh static RAM with proven long-term availability and backward-compatible footprints.
FAQ
What is the maximum operating frequency supported by IDT71256SA20YI8?
IDT71256SA20YI8 does not operate on a clock signal-it is an asynchronous static RAM. Its maximum effective throughput is determined by cycle time tRC = 20 ns, supporting up to 50 MHz sustained random-access bandwidth. This enables direct interfacing with 50 MHz microcontroller buses without wait states or synchronization logic.
Does IDT71256SA20YI8 require external refresh circuitry?
No, IDT71256SA20YI8 is a fully static RAM and requires no refresh cycles or external refresh circuitry. Its CMOS latch-based memory cells retain data indefinitely as long as VCC is applied and CS is held low during active use-eliminating complexity in real-time deterministic systems.
Can IDT71256SA20YI8 be used with 3.3 V microcontrollers?
IDT71256SA20YI8 is specified for 4.5–5.5 V operation only and is not 3.3 V tolerant. Direct connection to 3.3 V logic risks violating VIH/VIL thresholds and may cause unreliable reads/writes. Level translation (e.g., TXB0108) is required for mixed-voltage systems.
What is the meaning of the 'YI8' suffix in IDT71256SA20YI8?
In IDT71256SA20YI8, 'Y' denotes 300-mil Plastic SOJ (PJG28) package, 'I' indicates Industrial temperature grade (–40°C to +85°C), and '8' specifies tape-and-reel packaging (8 mm carrier tape, 1,000 units/reel)-standard for automated SMT placement.
Is IDT71256SA20YI8 RoHS compliant and halogen-free?
Yes, IDT71256SA20YI8 is a Renesas "Green" part-fully RoHS compliant (2011/65/EU) and halogen-free per IEC 61249-2-21. This is confirmed in the datasheet's Ordering Information section and applies to all PZG/YG/TPG package variants manufactured after April 2011.
IDT71256SA20YI8 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 28-BSOJ (0.300", 7.62mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Memory Type:
- Volatile
- Memory Format:
- SRAM
- Technology:
- SRAM - Asynchronous
- Memory Size:
- 256Kbit
- Memory Organization:
- 32K 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:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-SOJ
IDT71256SA20YI8 FAQ
1.How can I place an order for IDT71256SA20YI8 through Aetrix?
Please submit a Request for Quotation (RFQ) for IDT71256SA20YI8 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 IDT71256SA20YI8 reliable?
The price and inventory of IDT71256SA20YI8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IDT71256SA20YI8 is usually 5 days.
3.What payment methods are accepted for IDT71256SA20YI8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IDT71256SA20YI8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for IDT71256SA20YI8?
IDT71256SA20YI8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your IDT71256SA20YI8 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 IDT71256SA20YI8?
For technical support, including IDT71256SA20YI8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IDT71256SA20YI8 requirements.
6.How does Aetrix verify that IDT71256SA20YI8 is sourced from the original manufacturer or authorized distributors?
All IDT71256SA20YI8 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 IDT71256SA20YI8 meets industry standards.
7.What is the process for return or replacement of IDT71256SA20YI8?
All IDT71256SA20YI8 units undergo pre-shipment inspection (PSI). If there is an issue with IDT71256SA20YI8, 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 IDT71256SA20YI8 part is unused and in its original packaging.
Return procedure for IDT71256SA20YI8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
IDT71256SA20YI8 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…
