AMD Xilinx DS180 uses XC7K325T-2FBG900C as the 7 Series ordering example. Read it as XC7K325T | -2 | FB | G | 900 | C: device type, speed grade, package type, Pb-free field, pin-count identifier and temperature range.
The complete orderable part number matters. A request shortened to XC7K325T does not identify timing, package footprint, temperature range or material construction.
Open the full-size Kintex-7 ordering diagram and zoom.
Decode XC7K325T-2FBG900C field by field #
| Field | Example | Official meaning | Procurement check |
|---|---|---|---|
| Device type | XC7K325T | Commercial-grade Kintex-7 325T device | Do not substitute XA automotive or XQ defense-grade prefixes without a separate qualification review. |
| Speed grade | -2 | Standard -2 timing grade | -3 is faster; -1 is slower. L and G modifiers change power, voltage or transceiver characteristics. |
| Package type | FB | Flip-chip BGA package family | Package type must stay attached to the following Pb-free character and pin identifier. |
| Pb-free field | G | RoHS 6/6 with Exemption 15 for FBG packages | G has a different published meaning in some other 7 Series package families. |
| Pin identifier | 900 | 900 package designation | AMD warns that a package name might not exactly equal the physical pin count; use UG475. |
| Temperature | C | Commercial, 0°C to +85°C junction | E is 0°C to +100°C; I is -40°C to +100°C. |
Device type and density are not interchangeable #
The XC7K325T device contains 326,080 logic cells, 840 DSP slices, 16,020 Kb of block RAM and 16 GTX transceivers according to DS180. Other Kintex-7 members range from XC7K70T through XC7K480T, but a larger number is not a transparent replacement. Logic, RAM, DSP, GTX count, I/O banks and available packages all change by member.
The initial XC also matters. This guide covers standard commercial Kintex-7 ordering syntax. XA and XQ products have automotive or defense-grade requirements, screening and supported combinations that must be checked in their own official data sheets.
Speed grade has performance, voltage and power implications #
For Kintex-7, -3 is the highest-performance standard grade, followed by -2 and -1. The ordering figure also documents -L1, -L2 and -G2 forms. L identifies lower-power speed grades; DS180 notes that -L2 can involve 1.0 V, 0.9 V or 0.95 V combinations depending on device and temperature. G2 identifies -2 devices with higher-performance transceivers.
Therefore, replacing -2 with -3 is not merely buying a faster label. The exact device, package and temperature combination must exist, and engineering must review timing, power, voltage rails and GTX requirements. Replacing -2 with -1 is a downgrade and requires a complete timing closure review.
FBG900 is one package identity #
FB, G and 900 are separate decoded fields, but together they form the package identity FBG900. DS180 lists FBG484, FBG676, FFG676, FBG900, FFG900, FFG901 and FFG1156 for Kintex-7, all at 1.0 mm ball pitch. The body sizes range from 23 × 23 mm to 35 × 35 mm.
AMD explicitly states that FBG900 and FFG900 are footprint compatible, as are FBG676 and FFG676. That official statement is a useful screening signal, not permission to exchange any two devices carrying those packages. The selected member must be supported in both packages, and GTX capability differs: DS180 limits GTX transceivers in FBG676 and FBG900 to 6.6 Gb/s, while the package and signal-integrity requirements still need project review.
Temperature substitution example #
DS180 lists both -2C and -2I for XC7K325T. Consequently, XC7K325T-2FBG900I can be an engineering alternate candidate when XC7K325T-2FBG900C is unavailable: device, speed and FBG900 package remain unchanged, while I extends the lower junction-temperature limit from 0°C to -40°C and the upper limit from +85°C to +100°C.
This is a one-way environmental upgrade candidate, not automatic pin-to-pin approval. Engineering should confirm the exact I-grade OPN is orderable, compare the package pinout file, rerun implementation for the target, review timing and power, and update the approved-vendor record. Industrial-grade stock can also cost more. A C-grade device cannot replace an I-grade requirement in the reverse direction.
Pin-to-pin and footprint boundaries #
The same FBG900 suffix is necessary for the closest mechanical replacement but does not prove electrical compatibility between different Kintex-7 densities. DS180's package table shows which devices are offered in each package and how many HR and HP I/Os and GTX channels are available. UG475 and the AMD package pinout files are the authority for actual ball assignments.
Before approving a substitute, compare every power, configuration, JTAG, GTX reference-clock, XADC and user-I/O ball. Recompile the design for the proposed target in Vivado and review pin planning, timing, transceiver and power reports. A package-body match without this work is only footprint similarity.
Procurement checklist #
- Copy the complete OPN from the released BOM, including speed and temperature grades.
- Match the XC7K device type and exact density before considering an alternate.
- Keep FB, G and 900 together as the full FBG900 package identity.
- Verify the device-package combination, body size, pitch and package pinout in DS180 and UG475.
- Treat faster speed or wider temperature coverage as engineering candidates, not purchasing approval.
- Check GTX rate, I/O-bank population, voltage rails and all assigned balls.
- Recompile for the proposed device and review timing, power and programming output.
- Confirm lifecycle, traceability, date code, moisture condition, packing medium, quantity, lead time and price.
Conclusion #
A Kintex-7 OPN is complete only when device type, speed, package, Pb-free field, pin identifier and temperature are present. Same-device FBG900 industrial stock can be a practical shortage candidate for a commercial part, but official package support, exact pinout and a project-specific Vivado review still determine whether it is safe to use.
Official references #
- AMD Xilinx 7 Series FPGAs Data Sheet: Overview DS180
- AMD Xilinx 7 Series Packaging and Pinout Specification UG475
- AMD Xilinx Kintex-7 DC and AC Switching Characteristics DS182
- AMD Kintex-7 FPGA product overview and product table
- AMD board and system design package-pinout resources