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Microchip Technology AT17C256-10SI
- Part No.:
- AT17C256-10SI
- Manufacturer:
- Microchip Technology
- Category:
- Configuration PROMs for FPGAs
- Package:
- 20-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
AT17C256-10SI.pdf
- Description:
- IC EEPROM FPGA 256KB 20-SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,652
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Product details
Overview
AT17C256-10SI from Microchip Technology (formerly Atmel) is a 256K-bit serial EEPROM FPGA configuration memory with 5V ±10% industrial supply, 20-lead PLCC package, and cascading CEO output for multi-FPGA daisy-chain loading in Master Serial Mode. It stores full bitstream configuration for Xilinx XC4000/SPARTAN, Altera FLEX, and Lucent ORCA FPGAs.
For engineers reviewing the AT17C256-10SI datasheet, AT17C256-10SI pinout, AT17C256-10SI application, or AT17C256-10SI equivalent, key selection criteria include cascading support for >128K configurations, programmable reset polarity, in-system programmability via 2-wire bus, and compatibility with SRAM-based FPGA master serial interfaces.
Technical Context
The AT17C256-10SI operates in Master Serial Mode, where FPGA CCLK drives its CLK input and DATA output feeds FPGA DIN. Its CEO output enables chaining of multiple AT17C/LV128/256 devices by asserting low after final bit read to enable next device's DATA line.
Reset polarity (active-high or active-low) is user-programmable via EEPROM byte; SER_EN must be high during FPGA configuration and pulled low only for 2-wire ISP programming. CE-driven standby mode reduces current to ≤150 µA at 5V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Memory Size | 262,144 × 1-bit (256K-bit) nonvolatile configuration storage |
| Supply Voltage | 5V ±10% - supports industrial temperature range (–40°C to +85°C) |
| Max Clock Frequency | 12.5 MHz (non-cascaded), 10 MHz (cascaded) - defines FPGA configuration speed limit |
| Standby Current | ≤150 µA - enables low-power system-level power gating when CE = high |
| Output Drive | Open-collector DATA with 4 mA sink capability - compatible with FPGA DIN termination schemes |
| Cascade Support | CEO output with 35–40 ns CLK-to-CEO delay - enables deterministic daisy-chain timing for multi-device configs |
| Reset Polarity | Programmable active-high or active-low - eliminates need for external inverters in reset path |
Pinout & Package
AT17C256-10SI uses a 20-lead Plastic J-Leaded Chip Carrier (PLCC) package with 0.400" body width and JEDEC MS-018 AA standard footprint.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | DATA | Bi-directional open-collector output for configuration bitstream; driven by EEPROM, loaded into FPGA DIN |
| 2 | CLK | Input clock synchronized to FPGA CCLK; increments internal address counter on rising edge |
| 3 | (WP) RESET/OE | Programmable reset input (active-high or active-low); also serves as write-protect when CE = low |
| 5 | CE | Chip Enable - high disables counters and forces standby mode; low enables DATA output with OE logic |
| 10 | GND | Ground reference for all I/O and core logic; requires 0.2 µF decoupling capacitor |
| 14 | CEO (A2) | Cascade-enable output - goes low after last bit read to enable next EEPROM in chain; A2 used for device ID in ISP mode |
| 17 | SER_EN | Serial enable - high enables FPGA configuration mode; low enables 2-wire ISP programming |
| 20 | VCC | +5V ±10% power supply - powers EEPROM core and I/O; supports industrial temperature operation |
Key Features
| Feature | Design Value |
|---|---|
| In-system programmability | 2-wire serial interface (SER_EN low) enables field reprogramming without socket removal |
| Cascadable architecture | CEO output allows daisy-chaining up to 128K/256K configurations - extends memory beyond single-device limits |
| SRAM FPGA compatibility | Direct interface with Xilinx XC4000/SPARTAN, Altera FLEX, Atmel AT40K, Lucent ORCA - no glue logic required |
| Programmable reset polarity | User-configurable active-high/low RESET/OE eliminates external inverter and simplifies system reset integration |
| Low-power standby | ≤150 µA ICCS at 5V - reduces system quiescent power when FPGA is not configuring |
Applications
| Industrial PLC Configuration | Xilinx SPARTAN FPGA Boot |
|---|---|
|
Use Scenario: Reconfigurable logic modules in factory automation controllers require reliable, field-upgradable bitstream storage across temperature cycling and vibration. IC Role / Device Role / Timing Role: AT17C256-10SI provides nonvolatile, single-pin serial configuration memory that loads on power-up in Master Serial Mode. Use Value: Industrial-grade 5V ±10% operation and –40°C to +85°C rating ensure stable boot under harsh plant-floor conditions. |
Use Scenario: Cost-sensitive embedded systems using Xilinx SPARTAN FPGAs need compact, low-pin-count configuration memory with minimal board space. IC Role / Device Role / Timing Role: AT17C256-10SI delivers 256K-bit bitstream via 8-pin SOIC-compatible interface, synchronized to FPGA CCLK. Use Value: PLCC package offers robust socketing for prototyping; cascading CEO supports future FPGA upgrades without PCB redesign. |
| Altera FLEX-Based Test Equipment | Multi-FPGA Telecommunications Line Card |
|
Use Scenario: Automated test instruments use Altera FLEX FPGAs for real-time signal generation and require fast, deterministic configuration reload. IC Role / Device Role / Timing Role: AT17C256-10SI supplies full configuration data at 12.5 MHz clock rate, meeting FLEX device startup timing. Use Value: Programmable reset polarity aligns with instrument's existing reset architecture - no layout changes needed. |
Use Scenario: High-density telecom line cards integrate multiple FPGAs for protocol processing and require coordinated, synchronized configuration. IC Role / Device Role / Timing Role: AT17C256-10SI acts as first-stage configurator with CEO driving CE of second AT17C256-10SI in daisy chain. Use Value: Cascaded CEO timing (35–40 ns CLK-to-CEO) ensures sub-100 ns inter-device handoff - avoids configuration gaps. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar FPGA configuration memory applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| AT17LV256-10SI | 3.3V ±10% supply, 10 MHz max clock (cascaded), lower ICCA (5 mA) | Targets 3.3V FPGA systems; incompatible with 5V-only designs | Select when host FPGA and power rail operate at 3.3V and industrial temp is required |
| XCR3256XL-10VQG100I | Integrated CPLD with on-chip configuration memory; no external EEPROM needed | Eliminates discrete config memory but fixes FPGA type and size; not upgradeable | Choose for cost-optimized, fixed-function designs where FPGA flexibility is not required |
Compared with AT17LV256-10SI, the AT17C256-10SI supports higher clock rates in non-cascaded mode and maintains compatibility with legacy 5V FPGA platforms; versus integrated CPLDs, it preserves full FPGA vendor and density flexibility while enabling field updates.
Availability
AT17C256-10SI is available at Aetrix Electronics and suitable for industrial PLCs, Xilinx SPARTAN-based embedded systems, Altera FLEX test equipment, telecommunications line cards, and FPGA development platforms requiring stable component supply across extended temperature ranges.
Supply support for AT17C256-10SI 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
Microchip Technology acquired Atmel in 2016 and continues to manufacture, support, and qualify legacy Atmel FPGA configuration EEPROMs including the AT17 series.
The AT17C/LV family was designed specifically for reliable, pin-efficient configuration of SRAM-based FPGAs in industrial, telecom, and embedded applications - emphasizing cascade scalability, in-system programmability, and wide-temperature operation.
FAQ
What is the operating voltage range for AT17C256-10SI?
The AT17C256-10SI operates at 5V ±10%, supporting an industrial temperature range of –40°C to +85°C. This 4.5V to 5.5V window ensures compatibility with legacy 5V FPGA systems and provides margin against rail droop during configuration bursts. The AT17C256-10SI does not support 3.3V operation - for that, the AT17LV256-10SI variant is required.
How does the CEO pin function in a cascaded configuration with AT17C256-10SI?
In cascade mode, the CEO pin of the AT17C256-10SI asserts low on the clock cycle immediately following the last configuration bit, disabling its DATA driver and enabling the CE input of the next AT17C/LV128/256 device. This handoff occurs with 35–40 ns CLK-to-CEO delay (industrial grade), ensuring deterministic timing between devices. The AT17C256-10SI must be placed before any AT17C/LV65 in the chain, as the latter lacks CEO output.
Can AT17C256-10SI be programmed in-circuit without removing it from the board?
Yes - the AT17C256-10SI supports in-system programming (ISP) via its 2-wire serial interface when SER_EN is pulled low. Programming occurs at VCC (5V) with no external high-voltage supply required, as internal charge pumps generate necessary programming voltages. The AT17C256-10SI retains full read/write functionality during ISP, and industry-standard programmers (e.g., ATDH2200E) are compatible.
Which FPGAs are explicitly supported by AT17C256-10SI according to official documentation?
Atmel's datasheet confirms direct compatibility with Xilinx XC3000/XC4000/XC5200/SPARTAN families, Altera FLEX devices, Lucent ORCA FPGAs, Atmel AT40K and AT6000 series, and Motorola MPA1000 FPGAs. Interface compliance is based on Master Serial Mode timing, pin mapping (CLK→CCLK, DATA→DIN), and reset synchronization - no FPGA-specific firmware or patches are required for AT17C256-10SI operation.
What is the purpose of the (WP) RESET/OE pin on AT17C256-10SI?
The pin labeled (WP) RESET/OE on the AT17C256-10SI serves dual functions: as RESET input (programmable active-high or active-low) to reset internal address counters during FPGA reboot, and as write-protect (WP) when CE is low - preventing writes to the lowest memory block. Its dual role eliminates need for separate reset and WP lines, reducing FPGA pin count and simplifying PCB routing. The AT17C256-10SI's programmable polarity removes external inverter requirements.
AT17C256-10SI Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 20-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Programmable:
- Not Verified
- Programmable Type:
- Serial EEPROM
- Memory Size:
- 256Kb
- Voltage - Supply:
- 4.5V ~ 5.5V
- Operating Temperature:
- -40°C ~ 85°C
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-SOIC
AT17C256-10SI FAQ
1.How can I place an order for AT17C256-10SI through Aetrix?
Please submit a Request for Quotation (RFQ) for AT17C256-10SI 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 AT17C256-10SI reliable?
The price and inventory of AT17C256-10SI are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AT17C256-10SI is usually 5 days.
3.What payment methods are accepted for AT17C256-10SI?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AT17C256-10SI transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AT17C256-10SI?
AT17C256-10SI orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AT17C256-10SI 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 AT17C256-10SI?
For technical support, including AT17C256-10SI datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AT17C256-10SI requirements.
6.How does Aetrix verify that AT17C256-10SI is sourced from the original manufacturer or authorized distributors?
All AT17C256-10SI 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 AT17C256-10SI meets industry standards.
7.What is the process for return or replacement of AT17C256-10SI?
All AT17C256-10SI units undergo pre-shipment inspection (PSI). If there is an issue with AT17C256-10SI, 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 AT17C256-10SI part is unused and in its original packaging.
Return procedure for AT17C256-10SI:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AT17C256-10SI Tags
-
AT17LV512A-10PU
Microchip Technology
-
EPCQ4ASI8N
Intel
-
AT17LV256-10PU
Microchip Technology
-
AT17LV256-10NU
Microchip Technology
-
EPCQ16ASI8N
Intel
-
AT17LV010-10PU
Microchip Technology
-
EPCQ32ASI8N
Intel
-
EPCQ64ASI16N
Intel
-
EPCQ128ASI16N
Intel
-
AT17LV512A-10JU
Microchip Technology
-
AT17LV512-10JU
Microchip Technology
-
AT17LV010-10JU
Microchip Technology
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