The XC1701-PD8I is a high-performance, one-time programmable (OTP) serial configuration PROM manufactured by AMD (formerly Xilinx). This industrial-grade memory device stores and automatically loads configuration bitstreams into Xilinx FPGA devices during power-up, making it essential for embedded systems requiring reliable, non-volatile FPGA configuration storage.

XC1701-PD8I Product Overview

The XC1701-PD8I belongs to the XC1700 family of configuration PROMs, designed specifically to store large FPGA configuration bitstreams. This device features a simple serial interface requiring only one user I/O pin, significantly reducing board complexity while ensuring reliable configuration every time the system powers on.

Key Features of the XC1701-PD8I Serial PROM

The XC1701-PD8I offers several advantages for FPGA-based designs:

• 1Mbit Memory Capacity: Stores 1,048,576 configuration bits, sufficient for many FPGA designs
• Industrial Temperature Range: Operates reliably from -40°C to +85°C
• Simple Serial Interface: Requires only one user I/O pin connection to the FPGA
• Cascadable Architecture: Multiple PROMs can be daisy-chained for larger bitstreams
• Programmable Reset Polarity: Supports both active-high and active-low reset configurations
• Fast Configuration Support: Enables rapid FPGA boot-up sequences

XC1701-PD8I Technical Specifications

XC1701-PD8I Pin Configuration

XC1701-PD8I Operating Modes

Master Serial Mode Configuration

In Master Serial mode, the FPGA generates the configuration clock that drives the XC1701-PD8I PROM. After a short access time following the rising clock edge, configuration data appears on the DATA output pin, which connects directly to the FPGA DIN input. The FPGA automatically generates the required number of clock pulses to complete configuration and then disables the PROM.

Slave Serial Mode Configuration

When the FPGA operates in Slave Serial mode, both the XC1701-PD8I PROM and the FPGA receive their clock signal from an external source. This mode enables synchronized configuration timing controlled by the system designer.

Cascading Multiple PROMs

For FPGA designs requiring more configuration data than a single XC1701-PD8I can store, multiple devices can be cascaded by connecting the CEO (Chip Enable Output) of one device to the CE (Chip Enable) input of the next. The clock and DATA outputs of all PROMs in the chain are interconnected, allowing seamless configuration of larger bitstreams.

Compatible FPGA Families

The XC1701-PD8I serial configuration PROM is compatible with numerous FPGA families including:

XC1701-PD8I Programming Information

Software Support

The XC1701-PD8I is programmed using either Xilinx Alliance or Foundation software, which compiles the FPGA design file into a standard Hex format. This format can be transferred to most commercial PROM programmers for device programming.

Programming Considerations

XC1701-PD8I Ordering Information

Design Recommendations for XC1701-PD8I

Power Supply Connections

Connect the VCC pin to a stable 5V power supply within the 4.5V to 5.5V operating range. The VPP pin must be connected to VCC during normal read operation to ensure predictable behavior across all operating temperatures.

Reset Configuration

The RESET/OE pin polarity is programmable. The default configuration is active-high reset, but active-low reset is preferred because it can be connected directly to the FPGA INIT pin in most configurations.

Board Layout Guidelines

• Place decoupling capacitors close to the VCC and GND pins
• Keep clock signal traces short and away from noisy signal lines
• Ensure proper grounding between the PROM and FPGA devices
• Consider adding pull-up resistors on the CE pin for reliable power-on behavior

XC1701-PD8I Applications

The XC1701-PD8I serial configuration PROM is ideal for applications requiring:

• Industrial control systems with extended temperature requirements
• Telecommunications equipment
• Automotive electronics
• Medical devices
• Aerospace and defense systems
• Test and measurement instruments
• Embedded computing platforms

Product Status and Availability

The XC1701-PD8I has been designated as obsolete by AMD (formerly Xilinx). For new designs, consider the following alternatives:

Summary

The XC1701-PD8I is a reliable 1Mbit serial configuration PROM designed for industrial-grade FPGA applications. Its simple interface, wide operating temperature range, and cascadable architecture make it suitable for demanding embedded systems. While this device is now obsolete, it remains available through electronic component distributors for legacy system maintenance and repair applications.

For current FPGA configuration memory solutions, designers should evaluate the XCF and XC18V series programmable configuration memories, which offer in-system programming capabilities and enhanced feature sets.