My Inquiry
My Account
Renesas IDT71256SA12TP
- Part No.:
- IDT71256SA12TP
- Manufacturer:
- Renesas
- Category:
- Memory
- Package:
- 28-DIP (0.300", 7.62mm)
- Datasheet:
-
IDT71256SA12TP.pdf
- Description:
- IC SRAM 256KBIT PARALLEL 28DIP
- Quantity:
- Payment:
- Shipping:
Inventory:3,120
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
IDT71256SA12TP from Renesas Electronics is a 32K × 8 (256 Kbit) high-speed CMOS static RAM with 12 ns access time, TTL-compatible I/O, single 5 V supply operation, and industrial-grade reliability in a 28-pin 300-mil plastic DIP package. It serves as fast, fully static asynchronous memory for embedded controllers, data acquisition systems, and legacy industrial PLCs requiring deterministic read/write timing without refresh.
For engineers reviewing the IDT71256SA12TP datasheet, IDT71256SA12TP pinout, IDT71256SA12TP application, or IDT71256SA12TP equivalent, key selection criteria include guaranteed 12 ns commercial-grade access time, bidirectional TTL-compatible I/O pins, low-power standby modes (ISB1 = 15 mA), and compatibility with legacy 28-pin memory sockets in avionics and test equipment designs.
Technical Context
The IDT71256SA12TP implements fully static asynchronous circuitry-no clocks or refresh required-and uses dual control logic for independent chip select (CS) and output enable (OE) signals, enabling fast 6 ns OE-to-output valid timing. Its address decoding supports 15-bit addressing (A0–A14) for full 32K word coverage with no wait states.
It features two distinct standby power modes: ISB (TTL-level CS deassertion, 50 mA max) and ISB1 (CMOS-level CS deassertion, 15 mA max), allowing system-level power optimization based on control signal drive strength. All inputs and outputs meet standard TTL voltage thresholds (VIH ≥ 2.2 V, VIL ≤ 0.8 V) at VCC = 5.0 V ±10%.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Organization | 32K × 8-bit (262,144-bit total); enables byte-wide data bus interfacing without external multiplexing |
| Access Time (tAA) | 12 ns max; guarantees deterministic read latency for real-time control loops running at ≤83 MHz effective bus rate |
| Supply Voltage | 4.5 V to 5.5 V; compatible with standard 5 V TTL/CMOS logic rails and legacy power domains |
| I/O Compatibility | TTL-compatible inputs and outputs; eliminates level-shifting requirements in mixed-logic systems |
| Standby Current (ISB1) | 15 mA max at VCC = 5.5 V; supports low-power hold mode during processor sleep without external gating |
| Operating Temperature | 0°C to +70°C (Commercial grade); validated for use in office automation, instrumentation, and non-automotive industrial enclosures |
| Package | 28-pin 300-mil plastic DIP (PTG28); direct drop-in replacement for legacy 28-pin memory sockets in repair and sustainment programs |
Pinout & Package
Package: 28-pin 300-mil plastic DIP (PTG28), through-hole mount, 0.300-inch width, JEDEC MS-011AC compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| A0–A14 | Address Inputs | 15-bit unidirectional address bus; selects one of 32,768 memory locations; no internal latching |
| I/O0–I/O7 | Bidirectional Data Bus | 8-bit TTL-compatible data path; direction controlled by WE and CS; high-impedance when deselected or OE high |
| CS | Chip Select Input | Active-low enable; places device in active or standby (ISB/ISB1) mode depending on logic level and timing |
| WE | Write Enable Input | Active-low write control; initiates write cycle when CS is low; OE must be high during writes |
| OE | Output Enable Input | Active-low output control; enables data output without deselecting chip; supports read-modify-write sequences |
| VCC | Power Supply | +5 V supply pin; decoupling capacitor required within 10 mm for stable 12 ns timing compliance |
| GND | Ground Reference | Signal and power ground; requires low-inductance connection to minimize noise coupling into address/data lines |
Key Features
| Feature | Design Value |
|---|---|
| Fully static asynchronous operation | No clock, no refresh, no wait states-simplifies timing design in microcontroller-based systems with irregular bus activity |
| Dual standby power modes (ISB/ISB1) | Enables system-level power management: ISB1 (15 mA) for deep sleep, ISB (50 mA) for fast wake-up readiness |
| 6 ns OE-to-output valid (tOE) | Supports high-speed burst reads in CPU co-processor interfaces where OE is strobed independently of CS |
| 12 ns guaranteed access time (tAA) | Meets timing closure for 80C88/80C86-based systems and FPGA soft-CPU memory interfaces at maximum rated frequency |
| TTL-compatible I/O with 5 V supply | Direct interface to legacy 5 V logic families (74LS, 74F, 8080/8085 buses) without level translators or bus buffers |
Applications
| Industrial Data Loggers | Legacy Test Equipment Controllers |
|---|---|
Use Scenario: Standalone battery-backed data logger capturing sensor readings at 10 kHz with local buffering before SD card transfer. IC Role / Device Role / Timing Role: Primary working memory for real-time sample storage; holds up to 32K samples before offload. Use Value: 12 ns access ensures zero-cycle-wait reads during high-speed ADC sampling bursts; TTL compatibility simplifies integration with 8051-based controller buses. | Use Scenario: Automated calibration system using GPIB-controlled instruments with onboard pattern generation and result caching. IC Role / Device Role / Timing Role: Fast scratchpad memory for waveform buffer and measurement result staging prior to host upload. Use Value: Dual standby modes reduce average power during idle periods between test sequences; 28-pin DIP allows field-replaceable module design. |
| Avionics Display Processors | Programmable Logic Controller (PLC) I/O Modules |
Use Scenario: Cockpit display unit rendering flight symbology with local frame buffer and command history cache. IC Role / Device Role / Timing Role: Low-latency memory for symbol overlay tables and recent command stack storage. Use Value: Guaranteed 12 ns tAA meets DO-254 deterministic timing budgets; commercial temp range aligns with certified cabin environment specs. | Use Scenario: Modular PLC backplane with hot-swappable I/O cards requiring local configuration and status storage. IC Role / Device Role / Timing Role: Non-refresh volatile memory for card-specific parameter tables and diagnostic logs. Use Value: Through-hole DIP package supports ruggedized, vibration-resistant PCB mounting; TTL I/O matches legacy 5 V backplane signaling. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-speed static RAM applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CY62256ELL-12ZXI | Same 32K × 8 organization, 12 ns access, but 32-pin SOIC package; lower ISB1 (5 mA) and wider industrial temp range (–40°C to +85°C) | Suitable for new designs requiring surface-mount assembly and extended temperature operation | Select if board space is constrained and reflow capability exists; not pin-compatible with IDT71256SA12TP's 28-pin DIP footprint |
| AS6C4008-12ZIN | 32K × 8, 12 ns, 28-pin SOJ package; higher ICC (180 mA) but same ISB1 (15 mA); RoHS-compliant green variant available | Preferred for cost-sensitive industrial upgrades where SOJ socket reuse is possible | Choose for legacy SOJ-based systems; requires PCB layout change versus DIP, but shares identical timing and logic interface |
Compared with CY62256ELL-12ZXI and AS6C4008-12ZIN, the IDT71256SA12TP offers direct 28-pin DIP compatibility for repair and sustainment of aging 5 V systems, while maintaining identical 12 ns timing and TTL I/O-but lacks extended temperature support and RoHS green certification found in newer alternatives.
Availability
IDT71256SA12TP is available at Aetrix Electronics and suitable for industrial data loggers, legacy test equipment controllers, avionics display processors, and programmable logic controller (PLC) I/O modules requiring stable component supply across long-lifecycle programs.
Supply support for IDT71256SA12TP 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 delivering microcontrollers, analog, power, and memory solutions for automotive, industrial, and enterprise applications.
The IDT71256SA12TP belongs to Renesas' legacy high-speed CMOS SRAM product line, designed specifically for 5 V TTL-system memory expansion and drop-in replacement in aging industrial and instrumentation platforms.
FAQ
What is the maximum operating frequency supported by the IDT71256SA12TP?
The IDT71256SA12TP does not operate on a clock signal-it is a fully static asynchronous SRAM. Its performance is defined by timing parameters, not frequency. With a 12 ns access time (tAA), it supports effective bus cycles up to approximately 83 MHz when used with compatible controllers, assuming no wait states. The read cycle time (tRC) is also 12 ns, enabling sustained high-speed random access without refresh overhead.
Does the IDT71256SA12TP require a refresh circuit or external clock?
No, the IDT71256SA12TP requires neither a refresh circuit nor an external clock. It uses fully static CMOS design with no dynamic nodes, meaning data retention is maintained indefinitely as long as VCC and GND are applied and inputs remain stable. This eliminates refresh overhead and simplifies integration with microcontrollers, FPGAs, and discrete logic systems.
Can the IDT71256SA12TP be used in place of older 28-pin SRAMs like the 62256 or HM62256?
Yes, the IDT71256SA12TP is functionally and pin-compatible with industry-standard 32K × 8 SRAMs such as the 62256 and HM62256, sharing identical pinout (PTG28 DIP), TTL-compatible I/O levels, and control signal behavior (CS/OE/WE). Its 12 ns speed is faster than many legacy versions, making it a performance upgrade with no hardware changes required.
What are the power consumption characteristics of the IDT71256SA12TP during active and standby operation?
In active operation (CS low, reads/writes occurring), the IDT71256SA12TP draws up to 160 mA (ICC) at VCC = 5.5 V. In TTL-level standby (CS high, OE high), current drops to ≤50 mA (ISB). In CMOS-level standby (CS > VHC), it further reduces to ≤15 mA (ISB1), enabling significant power savings during idle periods without losing data integrity.
Is the IDT71256SA12TP RoHS-compliant and lead-free?
The IDT71256SA12TP is a legacy part originally released prior to full RoHS enforcement. While Renesas documentation confirms "Green parts available" for newer variants (e.g., PZG TSOP packages), the TP suffix (plastic DIP) is not listed in the Green ordering table. Therefore, IDT71256SA12TP is not RoHS-compliant and contains lead per exemption 7a; it is intended for legacy repair and non-RoHS-restricted applications only.
IDT71256SA12TP Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Renesas
- Series:
- -
- Package/Case:
- 28-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- 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:
- 12ns
- Access Time:
- 12 ns
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 28-PDIP
IDT71256SA12TP FAQ
1.How can I place an order for IDT71256SA12TP through Aetrix?
Please submit a Request for Quotation (RFQ) for IDT71256SA12TP 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 IDT71256SA12TP reliable?
The price and inventory of IDT71256SA12TP are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IDT71256SA12TP is usually 5 days.
3.What payment methods are accepted for IDT71256SA12TP?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IDT71256SA12TP transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for IDT71256SA12TP?
IDT71256SA12TP orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your IDT71256SA12TP 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 IDT71256SA12TP?
For technical support, including IDT71256SA12TP datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IDT71256SA12TP requirements.
6.How does Aetrix verify that IDT71256SA12TP is sourced from the original manufacturer or authorized distributors?
All IDT71256SA12TP 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 IDT71256SA12TP meets industry standards.
7.What is the process for return or replacement of IDT71256SA12TP?
All IDT71256SA12TP units undergo pre-shipment inspection (PSI). If there is an issue with IDT71256SA12TP, 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 IDT71256SA12TP part is unused and in its original packaging.
Return procedure for IDT71256SA12TP:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
IDT71256SA12TP 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…
