Microchip Technology AT17F32A-30BJU

Overview

AT17F32A-30BJU from Atmel is a 32-Mbit (33,554,432 × 1-bit) in-system programmable serial configuration PROM designed to store and deliver FPGA bitstreams in Master Serial mode. It operates at 3.3V ±10%, features 5V-tolerant I/O pins, supports cascading via nCASC, and delivers configuration data to SRAM-based FPGAs including Altera Cyclone™ and Stratix™ families.

For engineers reviewing the AT17F32A-30BJU datasheet, AT17F32A-30BJU pinout, AT17F32A-30BJU application, or AT17F32A-30BJU equivalent, this device serves as a dedicated, non-volatile configuration memory with page-select capability, ISP support via 2-wire bus, and industrial-grade (-40°C to +85°C) operation in 44-lead PLCC packaging.

Technical Context

The AT17F32A-30BJU implements a serial flash-based architecture with an internal address counter, tri-state DATA output, and synchronous DCLK-driven readout. Its control logic responds directly to FPGA signals-nCS, RESET/OE, and DCLK-enabling autonomous configuration without external controllers.

It supports four-page partitioning (via PAGE_EN and PAGESEL[1:0]) for storing multiple bitstreams, and includes cascade logic where nCASC asserts low upon end-of-memory to enable daisy-chained devices. SER_EN selects between FPGA configuration mode (High) and 2-wire ISP programming mode (Low).

Key Specifications

Pinout & Package

AT17F32A-30BJU is housed in a 44-lead Plastic Leaded Chip Carrier (PLCC), JEDEC MS-018 AC compliant, with 1.27 mm pitch, J-lead profile, and 17.4 mm × 17.4 mm body dimensions.

Key Features

Applications

Equivalent & Alternatives

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

Compared with EPCS16SI8N and M25P32-VME6TG, the AT17F32A-30BJU uniquely integrates FPGA-specific control logic (nCASC, READY, PAGE_EN), supports true Master Serial mode without host intervention, and enables multi-bitstream management-making it optimal for deterministic, self-contained FPGA boot in industrial systems.

Availability

AT17F32A-30BJU is available at Aetrix Electronics and suitable for industrial PLCs, telecommunications baseband boards, reconfigurable test equipment, and legacy FPGA upgrade programs requiring stable component supply and long-lifecycle support.

Supply support for AT17F32A-30BJU 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 was a U.S.-based semiconductor manufacturer specializing in microcontrollers, non-volatile memory, and programmable logic solutions before its acquisition by Microchip Technology in 2016.

The AT17FxxA series was designed specifically to provide robust, in-system programmable configuration memory for SRAM-based FPGAs operating in industrial environments, emphasizing ease of integration, cascading scalability, and field-upgradability.

FAQ

What is the primary function of the AT17F32A-30BJU in an FPGA-based system?

The AT17F32A-30BJU serves as a dedicated serial configuration PROM that stores and delivers FPGA bitstreams during power-up or reset. It operates in Master Serial mode, driving the FPGA's DIN and DCLK pins autonomously without external controller intervention. The AT17F32A-30BJU integrates hardware features-including nCASC, READY, and PAGE_EN-that streamline FPGA boot sequencing, cascading, and multi-bitstream management in industrial designs.

Does the AT17F32A-30BJU support in-system programming (ISP), and how is it enabled?

Yes, the AT17F32A-30BJU supports in-system programming via a 2-wire serial interface. ISP is activated by driving the SER_EN pin Low, which places the device into programming mode. In this state, industry-standard programmers-including Atmel's ATDH2200E system-can read, verify, and reprogram the configuration memory without removing the AT17F32A-30BJU from the PCB. During normal FPGA operation, SER_EN must remain High (typically tied to VCC).

How does the page-select feature of the AT17F32A-30BJU improve system reconfiguration capability?

The AT17F32A-30BJU supports four independent 8-Mbit memory pages when PAGE_EN is asserted High. Using PAGESEL0 and PAGESEL1 inputs, users can select any of the four pages to load distinct FPGA bitstreams-enabling rapid reconfiguration for different operational modes (e.g., test vs. production, protocol A vs. protocol B). This eliminates the need for multiple PROMs or external logic, and the AT17F32A-30BJU retains full compatibility with standard Master Serial timing and control signals.

What is the role of the nCASC pin on the AT17F32A-30BJU, and how is it used in cascaded configurations?

The nCASC pin on the AT17F32A-30BJU is a cascade select output that goes Low when the internal address counter reaches the end of its memory space. In a daisy-chain setup, nCASC from one AT17F32A-30BJU connects to the nCS input of the next device, automatically enabling its DATA output once the first device completes transmission. This hardware handoff ensures seamless, deterministic expansion of configuration memory across multiple AT17F32A-30BJU units without software or timing overhead.

Is the AT17F32A-30BJU compatible with Altera (now Intel) FPGAs, and which families are explicitly supported?

Yes, the AT17F32A-30BJU is explicitly compatible with Altera FLEX®, Excalibur™, Stratix™, Cyclone™, and APEX™ FPGAs. Its timing parameters, pinout behavior (e.g., DCLK output, nCS synchronization), and Master Serial protocol implementation align with Altera's configuration specifications. The AT17F32A-30BJU has been validated for direct interface with these families without additional glue logic, and its READY and RESET/OE signals coordinate cleanly with Altera FPGA reset and initialization sequences.