Microchip Technology AT17C512A-10JI

Overview

AT17C512A-10JI from Atmel is a 512-kilobit serial EEPROM FPGA configuration memory designed specifically for Altera FLEX® devices, operating at 5V ±10% over -40°C to +85°C industrial range, featuring programmable reset polarity, in-system programmability via 2-wire bus, and cascading support for multi-device configuration chains.

For engineers reviewing the AT17C512A-10JI datasheet, AT17C512A-10JI pinout, AT17C512A-10JI application, or AT17C512A-10JI equivalent, key selection criteria include industrial temperature rating, PDIP/PLCC package compatibility with legacy Altera EPC1441 replacement, READY pin availability in PLCC, and master/slave clocking mode flexibility for FPGA configuration sequencing.

Technical Context

The AT17C512A-10JI implements a dedicated serial configuration interface with OE (active-High output enable / active-Low reset), nCS (active-Low chip select), and DCLK (bidirectional clock) pins that directly drive Altera FPGA DATA0 and nCONFIG signals. Its internal oscillator enables autonomous "master" operation, while SER_EN-controlled programming mode supports 2-wire in-system reprogramming without external high-voltage sources.

It supports daisy-chained configuration via nCASC (active-Low cascade output) and A2 device-select input during programming, with WP1 write-protect pin disabling memory modification during FPGA loading. The READY pin provides open-collector power-on reset status indication, synchronized to internal VCC stabilization-not system-level voltage monitoring.

Key Specifications

Pinout & Package

AT17C512A-10JI is available in 20-lead PLCC (20J) and 8-lead PDIP (8P3) packages; the J-suffix denotes industrial temperature grade. The PLCC variant includes READY and WP1 pins; PDIP omits READY.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT17LV512A-10JI and EPC1441, the AT17C512A-10JI delivers 5V operation with faster timing, industrial-grade reliability, and enhanced system integration via READY and WP1-making it optimal for legacy 5V FPGA designs requiring robustness and serviceability.

Availability

AT17C512A-10JI is available at Aetrix Electronics and suitable for industrial PLCs, telecom baseband modules, and defense radar signal processors requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AT17C512A-10JI 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.

The AT17A Series was designed explicitly for reliable, low-complexity configuration of Altera FLEX® FPGAs-emphasizing ease of integration, cascading scalability, and industrial environmental resilience.

FAQ

What is the primary function of the AT17C512A-10JI in an FPGA-based system?

The AT17C512A-10JI serves as a dedicated serial configuration EEPROM that stores and loads the bitstream into Altera FLEX® FPGAs at power-up. It autonomously clocks data out via its internal oscillator or synchronizes to an external clock, supporting both single-device and cascaded configurations. Its design eliminates the need for external controllers during FPGA initialization, making AT17C512A-10JI essential for deterministic, self-contained FPGA boot sequences in industrial and defense applications.

Does the AT17C512A-10JI support in-system programming, and how is it enabled?

Yes, the AT17C512A-10JI supports in-system programming via a 2-wire serial interface. Programming mode is activated by driving the SER_EN pin Low while maintaining valid VCC (5V ±10%). During this mode, DATA and DCLK serve as bidirectional SDA/SCL lines, and internal charge pumps generate required programming voltages-no external high-voltage supply is needed. This capability allows field updates of FPGA configuration data without device removal, a key feature of the AT17C512A-10JI for maintenance-sensitive deployments.

How does the READY pin on the AT17C512A-10JI improve FPGA power-up sequencing?

The READY pin on the AT17C512A-10JI is an open-collector output driven Low during internal power-on reset and tri-stated upon completion. When connected to the FPGA's nCONFIG pin (with appropriate pull-up), it holds the FPGA in reset until the EEPROM's internal state is fully stabilized-decoupling FPGA readiness from system VCC ramp time. This ensures deterministic configuration timing and prevents metastability or partial loading, a critical reliability enhancement provided by the AT17C512A-10JI in thermally demanding environments.

Can the AT17C512A-10JI replace the Altera EPC1441, and what are the key compatibility considerations?

Yes, the AT17C512A-10JI is documented as a direct replacement for the discontinued Altera EPC1441 in 512-kbit FPGA configuration roles. It shares identical pinouts for PDIP and PLCC packages, same 5V operation, and compatible serial protocol. However, AT17C512A-10JI adds the READY and WP1 pins-unused in EPC1441 designs-which provide enhanced reset coordination and memory protection. These additions are backward-compatible and do not require PCB changes, reinforcing AT17C512A-10JI's role as a drop-in upgrade.

What is the significance of programmable reset polarity in the AT17C512A-10JI, and how is it configured?

The AT17C512A-10JI allows OE pin behavior to be programmed as either active-High output enable / active-Low reset or active-Low output enable / active-High reset-set permanently during initial programming by writing four specific EEPROM bytes. For Altera FLEX® compatibility, it must be configured as active-High OE (reset active-Low), matching FPGA nCONFIG timing requirements. This one-time configuration ensures interoperability across FPGA families and eliminates board-level logic for polarity inversion, a design flexibility unique to the AT17C512A-10JI among legacy configuration memories.