AMD XC17256EPD8I

Overview

XC17256EPD8I from AMD is a 256-kbit serial PROM configured for Xilinx FPGA configuration, operating at 5 V with 100 ns access time and -40°C to +85°C industrial temperature range, used in embedded reconfiguration of Spartan and Virtex family FPGAs.

For engineers reviewing the XC17256EPD8I datasheet, pinout, applications, or equivalent options, key selection criteria include voltage compatibility with target FPGA configuration interface, read timing compliance, industrial-grade temperature operation, and PDIP-8 package fit for legacy prototyping and repair scenarios.

Technical Context

This device implements a one-time programmable (OTP) serial PROM architecture optimized for bitstream loading into Xilinx FPGAs via dedicated configuration pins (e.g., DIN, CCLK, INIT_B). It uses NMOS technology with internal address latching and automatic sequential read mode.

XC17256EPD8I supports standard SPI-compatible serial read protocol with active-low chip select (/CS), data output on falling edge of CCLK, and no write capability after initial programming - consistent with its role as a non-volatile configuration memory rather than a general-purpose EEPROM.

Key Specifications

Pinout & Package

XC17256EPD8I is housed in an 8-pin plastic dual in-line package (PDIP-8) with 0.3-inch body width, suitable for through-hole mounting on legacy development and production PCBs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA configuration memory applications.

Compared with XC17256EPD8I, XCF02SVO20C offers higher density and reprogrammability but demands 3.3 V operation and different packaging, while AT17LV256-10PU shares the PDIP-8 form factor but introduces voltage mismatch and endurance considerations that affect long-term field reliability in 5 V systems.

Availability

XC17256EPD8I is available at Aetrix Electronics and suitable for FPGA configuration in industrial controllers, legacy test equipment, and avionics subsystems requiring stable component supply over extended product lifecycles.

Supply support for XC17256EPD8I 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

AMD is a global semiconductor company specializing in high-performance computing, adaptive SoCs, and programmable logic solutions, with heritage in FPGA and configuration memory technologies.

XC17256EPD8I belongs to AMD's legacy Xilinx configuration PROM product line, designed specifically to provide reliable, one-time programmable bitstream storage for early-generation SRAM-based FPGAs.

FAQ

Is XC17256EPD8I reprogrammable after initial programming?

No, XC17256EPD8I is a one-time programmable (OTP) device. Once programmed using a compatible parallel programmer, its contents cannot be altered. This ensures configuration bitstream integrity in mission-critical applications where accidental or malicious modification must be prevented. XC17256EPD8I does not support in-system erase or rewrite functions.

What FPGA families is XC17256EPD8I officially qualified to configure?

XC17256EPD8I is documented by AMD to configure Spartan-XL, Spartan-II, and Virtex-E series FPGAs. Its timing parameters, voltage levels, and serial protocol match the configuration interface specifications of those families. XC17256EPD8I is not qualified for Virtex-4 or later generations due to changes in configuration architecture and voltage requirements.

Does XC17256EPD8I require external pull-up resistors on any pins?

Yes, XC17256EPD8I requires an external 4.7 kΩ pull-up resistor on the INIT_B pin to ensure proper FPGA initialization signaling. The DOUT pin also needs a pull-up if shared on a multi-drop bus, though this is optional in point-to-point FPGA configuration. XC17256EPD8I itself does not integrate internal pull-ups on these signals.

Can XC17256EPD8I operate at 3.3 V?

No, XC17256EPD8I is specified only for 5.0 V ±10% operation. Attempting to power it at 3.3 V will result in undefined behavior, including failure to output valid configuration data or improper initialization handshake with the FPGA. XC17256EPD8I must be used in 5 V systems or with appropriate level-shifting circuitry for mixed-voltage designs.

What is the maximum supported CCLK frequency for XC17256EPD8I?

The maximum guaranteed CCLK frequency for XC17256EPD8I is 10 MHz, derived from its 100 ns access time specification. At this rate, the device reliably outputs configuration bits aligned to the falling edge of CCLK. Exceeding 10 MHz may cause timing violations and corrupted FPGA configuration, especially under worst-case voltage and temperature conditions. XC17256EPD8I does not support faster clocks even with tighter process corners.