Microchip Technology AT17N040-10TQC

Overview

AT17N040-10TQC from Atmel is a 4-Mbit (4,194,304 × 1-bit) serial EEPROM FPGA configuration memory operating at 3.3V ±10%, designed for Master Serial mode loading of Xilinx Spartan-II, Spartan-IIE, and Spartan XL FPGAs. It features pin compatibility with XC17SXXXA/L PROMs, low-power standby mode (150 µA industrial), and 20-year data retention at 85°C.

For engineers reviewing the AT17N040-10TQC datasheet, AT17N040-10TQC pinout, AT17N040-10TQC application, or AT17N040-10TQC equivalent, this device serves as a drop-in replacement for legacy Xilinx-compatible configuration PROMs in commercial-temperature FPGA systems requiring reliable nonvolatile serial bitstream storage and deterministic power-up loading.

Technical Context

The AT17N040-10TQC implements a serial-access EEPROM architecture with tri-state DATA output, synchronous CLK-driven address counter, and dual-function RESET/OE pin that resets internal counters and controls output enable. SER_EN must be held high during FPGA configuration to disable ISP mode.

It interfaces directly with SRAM-based FPGAs using master serial protocol: FPGA CCLK drives AT17N040-10TQC CLK; AT17N040-10TQC DATA drives FPGA DIN; CE and RESET/OE are controlled by FPGA to manage output enable and counter reset. Standby current is 150 µA (industrial) when CE is high.

Key Specifications

Pinout & Package

AT17N040-10TQC is packaged in a 44-lead Thin Quad Flat Package (TQFP), 10 mm × 10 mm body, 1.0 mm thickness, 0.8 mm lead pitch (JEDEC MS-026 ACB). Pin 1 identifier located at top-left corner with 0°–7° chamfer.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT17LV040-10CU, AT17N040-10TQC offers proven field reliability in legacy systems but higher standby current; compared with XC17S40A, it adds reprogrammability and 10-cycle endurance at the cost of slightly higher active power - making AT17N040-10TQC optimal for maintenance-sensitive industrial upgrades.

Availability

AT17N040-10TQC is available at Aetrix Electronics and suitable for industrial automation, telecom infrastructure, and test equipment applications requiring stable component supply and long-term obsolescence mitigation.

Supply support for AT17N040-10TQC 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

Atmel Corporation (now part of Microchip Technology) is a semiconductor manufacturer specializing in microcontrollers, nonvolatile memory, and FPGA configuration solutions for industrial and embedded markets.

The AT17N series was designed specifically to replace Xilinx's obsolete XC17S PROM family with enhanced reprogrammability, industrial temperature support, and seamless integration into Spartan-II/E master serial FPGA configurations.

FAQ

What is the primary function of the AT17N040-10TQC in an FPGA system?

The AT17N040-10TQC serves as a serial configuration EEPROM that stores and delivers the bitstream to Xilinx Spartan-II, Spartan-IIE, and Spartan XL FPGAs in Master Serial mode. It eliminates the need for external controllers by allowing the FPGA to autonomously load its configuration upon power-up using signals like CLK, CE, and RESET/OE - ensuring deterministic startup behavior critical for industrial systems. The AT17N040-10TQC is essential for reliable, repeatable FPGA initialization without host processor intervention.

Is the AT17N040-10TQC pin-compatible with Xilinx XC17S40A PROMs?

Yes, the AT17N040-10TQC is explicitly designed to be pin-compatible with Xilinx XC17S40A and XC17S40L PROMs in the 44-lead TQFP package. Pin mapping for DATA, CLK, CE, RESET/OE, VCC, GND, and SER_EN matches exactly, enabling drop-in replacement in existing PCBs. However, AT17N040-10TQC adds two-wire ISP capability and EEPROM reprogrammability - features absent in the one-time-programmable XC17S40A - so firmware update workflows must be adapted accordingly.

What is the maximum clock frequency supported by the AT17N040-10TQC in industrial temperature range?

The AT17N040-10TQC supports a maximum clock frequency of 10 MHz across the full industrial temperature range (-40°C to +85°C), as specified in the AC Characteristics table. This allows full 4-Mbit configuration loading in approximately 420 ms under worst-case timing conditions. The 10 MHz limit ensures robust signal integrity and timing margin when interfacing with Spartan-II/E FPGAs' CCLK outputs, especially in electrically noisy industrial environments.

How does the SER_EN pin affect operation of the AT17N040-10TQC?

The SER_EN pin (Pin 35) determines operational mode: when held high (tied to VCC), the AT17N040-10TQC operates in standard FPGA configuration mode; when pulled low, it enters two-wire serial ISP programming mode. During normal FPGA boot, SER_EN must remain high - connecting it to VCC is mandatory. Misconnecting SER_EN to ground or floating it will prevent configuration and may cause unpredictable DATA bus behavior. The AT17N040-10TQC relies on this pin to isolate programming logic from runtime operation.

What is the standby current consumption of the AT17N040-10TQC at 85°C?

The AT17N040-10TQC draws 150 µA in standby mode (CE = high) at the maximum industrial temperature of 85°C, as confirmed in the DC Characteristics table. This value reflects worst-case leakage across process, voltage, and temperature corners. At room temperature (25°C), typical standby current is lower (~100 µA), but system-level power budgeting should use the 150 µA spec. This low quiescent draw makes the AT17N040-10TQC suitable for always-on industrial controllers where energy efficiency matters.