Altera Cyclone IV Ordering Codes and Replacement Guide

Altera Cyclone IV parts are often searched by a short family name such as EP4CE55, Cyclone IV E or Cyclone IV GX. That is enough to start a search, but it is not enough to release a purchase order. The complete ordering code carries the device member, package, temperature grade, speed grade and shipment suffix that determine whether a part can fit an approved design.

This guide explains how to read the code, how to compare common Cyclone IV variants, and how to handle a shortage without calling every same-family device an equivalent. The key procurement rule is simple: a higher temperature or faster speed grade may be a useful candidate, while a different package code is normally a board-level change.

The ordering-code interpretation below is based on Altera's Cyclone IV FPGA Device Family Overview. Electrical operating conditions and grade terminology should be checked against the Cyclone IV Device Datasheet and the current device-specific documentation before approval.

Key takeaways

• Quote and approve the complete orderable code, not only the EP4CE or EP4CGX member name.
• A same-member, same-package device with a wider temperature range or faster speed grade can be a replacement candidate, but still requires pinout, tool, timing, power and qualification review.
• A different package code is not a pin-to-pin substitute unless a board-level migration review proves otherwise.

Why the complete ordering code matters #

Two parts can share a Cyclone IV family and still differ in ways that affect the board, timing closure or qualification file. The differences most relevant to procurement are:

• device member and available logic resources;
• family variant, including whether the device is Cyclone IV E or Cyclone IV GX;
• package type, package code, pin or ball count, body size and pitch;
• commercial, industrial, extended-industrial or automotive temperature grade where applicable;
• speed grade and any low-voltage or other device option;
• lead-free, engineering-sample and packing suffixes.

For that reason, EP4CE55, EP4CE55F23, and EP4CE55F23C8N are not interchangeable procurement descriptions. The first is a device family/member reference, the second adds a package reference, and the third is a complete orderable code that can be checked against the released BOM.

How to read a Cyclone IV GX code #

The official GX ordering pattern can be shown as:

EP4C | GX | 30 | C | F | 19 | C | 7 | N

Concatenated, this becomes EP4CGX30CF19C7N.

The GX member codes in the official ordering figure are 15, 22, 30, 50, 75, 110 and 150. The same figure maps them to increasing logic capacity, but member code alone does not identify the package. For example, a GX member can appear in more than one FBGA package, so EP4CGX75 is not a complete replacement description for EP4CGX75CF23C8N.

Cyclone IV E uses a different ordering map #

Cyclone IV E keeps the EP4C family signature but does not use the GX transceiver-count field. A representative E-family pattern is:

EP4C | E | 40 | F | 29 | C | 8 | N

This corresponds to an EP4CE40 device in an F29 FBGA package, commercial temperature, speed grade 8 and lead-free packaging. The E-family map includes additional package types such as EQFP, UBGA and MBGA, as well as device options that are not part of the GX pattern.

The E-family member codes include 6, 10, 15, 22, 30, 40, 55, 75 and 115. Use the exact manufacturer ordering figure for the selected family and package; do not copy the GX transceiver field into an E-family code.

Compare the model before comparing the price #

The following catalogue examples illustrate why the complete code needs to stay visible during an RFQ:

The table is a selection aid, not a statement that any model is a drop-in replacement. A quote should preserve the exact manufacturer code, requested package and acceptance conditions.

Shortage substitution example: EP4CE6F17C8N to EP4CE6F17I7N #

Suppose the approved EP4CE6F17C8N is unavailable and a supplier proposes EP4CE6F17I7N. This is the kind of comparison a shortage article should explain clearly.

This makes EP4CE6F17I7N a potential pin-to-pin candidate, not an automatically approved replacement. The same member and F17 package are positive signals, but the engineering release should still verify the complete ball map, power rails, configuration image, Quartus device selection, timing closure and qualification requirements.

The candidate code is used here to demonstrate the decision process. The LimChip catalogue record and live RFQ must confirm whether that exact orderable code is currently available and commercially acceptable.

When a package difference blocks pin-to-pin replacement #

Package compatibility is a separate gate from logic capacity. An EP4CE6 part in an F17/F256 package and an EP4CE6 part in a U19/U256 package may share the same member but still have different body outlines, ball arrangements, assembly constraints or board footprints.

The official EP4CE6 pin-information file lists the pin information for F256/U256 and other package context. That document should be checked together with the package drawing and the released PCB data. If the package code changes, label the candidate not pin-to-pin until the board-level impact is proven.

The same rule applies to a change between FBGA, UBGA, MBGA, EQFP or QFN. Similar logic density does not override mechanical fit, ball or pin numbering, power-pin placement, thermal behavior or assembly capability.

A controlled substitution validation flow #

Use this order when a shortage forces a candidate review:

1. Freeze the approved code. Record the complete MPN, package, temperature grade, speed grade, suffix and approved manufacturer. 2. Match the member. Keep the same density and family variant unless engineering explicitly accepts a resource or architecture change. 3. Match the package. Compare package family, code, pin or ball count, body size, pitch, footprint and pinout. 4. Check grade direction. Confirm that the temperature range meets the system requirement and that the speed grade meets the timing requirement. 5. Rebuild the design evidence. Select the candidate in the vendor tool, compile the design, review timing and power, and check the configuration file. 6. Qualify the physical material. Confirm marking, date code, lot consistency, moisture-barrier condition, packing and traceability. 7. Release the commercial comparison. Compare price, MOQ, available quantity, lead time and shipment terms only after the technical candidate is accepted.

The result should be recorded as one of three labels: candidate pin-to-pin, engineering requalification required, or not pin-to-pin. This gives procurement a usable answer without presenting an unverified equivalent as a fact.

RFQ checklist for Cyclone IV parts #

A useful RFQ sentence is: “Please quote EP4CE6F17C8N, F17/F256 package, commercial grade, speed grade 8, lead-free packaging, target quantity and acceptable date-code window. If unavailable, quote EP4CE6F17I7N separately as an industrial speed-grade candidate and identify package, lot, traceability, price and lead-time differences.”

How this article supports model-level SEO #

The series article should rank for broader research terms such as Cyclone IV ordering information, EP4CE part number decoding, Cyclone IV package options and Cyclone IV FPGA replacement. It should explain the decision and link to exact model pages.

Each model page should remain responsible for the exact transactional query: the complete MPN, package, specifications, date-code checks and RFQ route. For example, the EP4CE6F17C8N model page should target the exact code, while this article explains why an F17 commercial code may be compared with an F17 industrial candidate.

This separation prevents a near-identical article for every suffix. It also gives buyers a clear path from a family search to an approved orderable code without hiding package or grade differences inside a generic “equivalent” label.

Conclusion #

Cyclone IV ordering starts with the family, but it ends with the complete orderable code. When supply is tight, the safest candidate is usually one that keeps the same device member and package while meeting or exceeding the required temperature and speed conditions. Even then, the candidate must pass pinout, tool, timing, power, qualification and physical-material checks.

If the package code changes, treat the part as a board-level change rather than a pin-to-pin replacement. Send the approved code, candidate code, package, grade, quantity, date-code and documentation requirements in the RFQ so the technical and commercial comparison remains auditable.

Official references #

• Cyclone IV FPGA Device Family Overview, Altera Device Handbook Volume 1
• Cyclone IV Device Datasheet, Altera Device Handbook Volume 3
• Pin Information for the Cyclone IV EP4CE6 Device
• Cyclone IV FPGA Product Table