AMD XC17S40SO20C

Overview

XC17S40SO20C from AMD (formerly Xilinx) is a serial configuration PROM designed to store and load configuration bitstreams into Spartan-3 FPGAs. It provides 4 Mbit storage capacity, operates at 5.0 V supply voltage, supports read access time of 25 ns, and uses SO20 surface-mount package. It is used in industrial control systems requiring reliable FPGA reconfiguration.

For engineers reviewing the XC17S40SO20C datasheet, pinout, applications, or equivalent options, key considerations include VCC tolerance, read timing compliance with Spartan-3 startup requirements, data retention lifetime, and SO20 footprint compatibility with legacy PCB layouts.

Technical Context

This PROM implements a synchronous serial interface compatible with Xilinx Spartan-3 FPGA configuration protocols. It features a single 5.0 V supply rail, no internal voltage regulation, and requires external pull-up on DATA output during read cycles. The device lacks write-protection pins or hardware security fuses.

Timing is defined by tACC (25 ns max), tPU (100 ns min), and tDF (5 ns min). It does not support dual-supply operation, JTAG programming, or in-system programmability - configuration must be performed offline using dedicated PROM programmers.

Key Specifications

Pinout & Package

XC17S40SO20C is housed in a 20-pin SOIC (Small Outline Integrated Circuit) package with 0.3 inch body width and 1.27 mm lead pitch. Pin numbering follows standard SO20 convention, with Pin 1 marked by notch or dot.

Key Features

Applications

Equivalent & Alternatives

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

Compared with XCF04SVO20C and ATMEL AT17LV512-10JC, XC17S40SO20C offers proven 5 V compatibility and SO20 footprint alignment with legacy Spartan-3 reference designs, making it optimal for cost-sensitive, volume-manufactured industrial boards where reprogramming is performed offline.

Availability

XC17S40SO20C is available at Aetrix Electronics and suitable for industrial automation, test instrumentation, and medical imaging equipment requiring stable component supply and long-term obsolescence management.

Supply support for XC17S40SO20C 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 acquired Xilinx in 2022; XC17S40SO20C was originally developed by Xilinx as part of its pre-acquisition configuration PROM family.

This device belongs to the XC17Sxx serial PROM product line, engineered specifically to provide factory-programmed, single-supply, nonvolatile configuration storage for Spartan-series FPGAs.

FAQ

Is XC17S40SO20C compatible with Spartan-3E FPGAs?

No. XC17S40SO20C is designed for Spartan-3 (not Spartan-3E) FPGAs. Spartan-3E devices require different configuration bitstream formats and voltage signaling levels. Using XC17S40SO20C with Spartan-3E may result in failed configuration or hardware damage due to incompatible VCCIO requirements and startup timing.

Can XC17S40SO20C be reprogrammed in-system?

No. XC17S40SO20C is a one-time programmable (OTP) PROM. It lacks JTAG interface, write-enable logic, or erase functionality. Reprogramming requires removal from the board and use of a dedicated PROM programmer such as the Xilinx Parallel Cable III or third-party compatible units.

What is the maximum clock frequency supported during configuration readout for XC17S40SO20C?

XC17S40SO20C does not have an internal clock; it responds synchronously to the FPGA's CCLK signal. With 25 ns access time, it supports CCLK frequencies up to approximately 20 MHz in master serial mode, assuming proper setup/hold timing margins are maintained per Spartan-3 datasheet specifications.

Does XC17S40SO20C include built-in write protection?

No. XC17S40SO20C has no hardware write-protection features such as WP# pin or software lock bits. Once programmed, data is permanently stored, but physical protection relies on secure programming procedures and controlled access to programming equipment - not on device-level security mechanisms.

Is XC17S40SO20C RoHS compliant?

Yes. XC17S40SO20C is manufactured in a RoHS-compliant process and carries the "C" suffix per Xilinx nomenclature, indicating commercial temperature grade and lead-free (Pb-free) packaging per JEDEC J-STD-609.