Microchip Technology ATDH2221-

Overview

ATDH2221 from Atmel is a 20-pin SOIC adapter designed to interface the ATDH2200 AT17 Series Configurator Programming Kit with 20-pin SOIC target devices. It provides mechanical and electrical compatibility for in-system programming of AT17LV/AT17F configuration PROMs, supports 3.3 V operation, and enables direct connection between the ATDH2200's programming header and SOIC-packaged memory devices.

For engineers reviewing the ATDH2221 datasheet, ATDH2221 pinout, ATDH2221 application, or ATDH2221 equivalent, this adapter is essential when integrating AT17-series configuration PROMs into FPGA-based systems using the ATDH2200 programming platform - particularly where SOIC packaging, board-level ISP routing, or legacy device reprogramming are required.

Technical Context

The ATDH2221 serves as a passive, zero-insertion-force (ZIF)-free mechanical interface that maps the 14-signal programming interface of the ATDH2200 (including VCC, GND, DATA, CLK, INIT, DONE, PROGRAM, and /CS) to the standard 20-pin SOIC footprint. It maintains signal integrity by preserving trace lengths and minimizing stubs on critical timing paths such as CLK and DATA.

No active logic, level shifting, or voltage regulation is implemented. The adapter operates strictly at 3.3 V, matching the AT17LV/AT17F family's I/O voltage specification, and relies on the ATDH2200 for all control sequencing and power delivery.

Key Specifications

Availability

ATDH2221 is available at Aetrix Electronics and suitable for FPGA configuration programming, industrial control system reconfiguration, embedded boot memory updates, and legacy AT17-series PROM field servicing requiring stable component supply and full traceability.

Supply support for ATDH2221 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, FPGAs, nonvolatile memory, and programmable logic solutions before its acquisition by Microchip Technology in 2016.

The ATDH2221 belongs to Atmel's FPGA development hardware product line, engineered specifically to extend the ATDH2200 configurator's compatibility across common AT17-series PROM package variants - enabling flexible, low-risk programming workflows in lab, manufacturing, and field service environments.

FAQ

What is the primary function of the ATDH2221?

The ATDH2221 is a passive 20-pin SOIC adapter that enables the ATDH2200 AT17 Series Configurator Programming Kit to program 20-pin SOIC-packaged AT17LV and AT17F configuration PROMs. It provides precise pin alignment and signal routing without active circuitry, ensuring reliable in-system programming of FPGA configuration memory. The ATDH2221 does not modify signals or voltages - it functions solely as a mechanical and electrical bridge.

Does the ATDH2221 support 5 V or mixed-voltage operation?

No. The ATDH2221 is designed exclusively for 3.3 V operation, consistent with the AT17LV/AT17F device family and the ATDH2200's output specification. It contains no voltage translation or level-shifting components. Using the ATDH2221 with 5 V systems risks damaging connected AT17-series PROMs and violates Atmel's recommended operating conditions for the ATDH2221 and associated programming hardware.

Can the ATDH2221 be used with non-Atmel SOIC memory devices?

No. The ATDH2221 is purpose-built for Atmel's AT17LV and AT17F series configuration PROMs in 20-pin SOIC packages. Its pinout, signal assignments (e.g., PROGRAM, INIT, DONE), and timing relationships match only Atmel's proprietary programming protocol. Interfacing with generic EEPROMs or flash memory will not yield functional configuration programming for Xilinx or Actel FPGAs.

Is a schematic or layout drawing available for the ATDH2221?

Atmel did not publish a standalone schematic for the ATDH2221, as it is a passive interconnect adapter with no active components. Mechanical drawings and pin-mapping details are provided in the ATDH2200 User Guide (Rev. 1421D–06/01), specifically in Section "Accessories" and Figure 7-1. The ATDH2221 uses direct trace routing - no vias, resistors, or capacitors - and follows strict 1:1 signal mapping from ATDH2200 header to SOIC pins 1–20.

How does the ATDH2221 differ from the ATDH2222 or ATDH2223 adapters?

The ATDH2221 is specific to 20-pin SOIC packages, while ATDH2222 targets 20-pin PLCC and ATDH2223 supports 8-lead SOIC devices. Each adapter has unique footprint geometry, pad layout, and internal trace routing - they are not interchangeable. The ATDH2221 cannot physically mount on a PLCC socket, and its pin mapping differs from ATDH2222's PLCC-to-ATDH2200 mapping per Atmel's accessory ordering table on page 7 of the FPGA IDS manual.