Pro Electron or EECA is the European type designation and registration system for active components (such as semiconductors, liquid crystal displays, sensor devices, electronic tubes and cathode-ray tubes). Pro Electron was set up in 1966 in Brussels, Belgium. In 1983 it was merged with the European Electronic Component Manufacturers Association (EECA) and since then operates as an agency of the EECA. The goal of Pro Electron is to allow unambiguous identification of electronic parts, even when made by several different manufacturers. To this end, manufacturers register new devices with the agency and receive new type designators for them.

Designation system

Examples of Pro Electron type designators are: Pro Electron took the popular European coding system in use from around 1934 for valves (tubes), i.e. the Mullard–Philips tube designation, and essentially re-allocated several of the rarely used heater designations (first letter of the part number) for semiconductors. The second letter was used in a similar way to the valves naming convention: "A" for signal diode, "C" for low-power bipolar transistor or triode, "D" for high-power transistor (or triode), and "Y" for rectifier, but other letter designations did not follow the vacuum tube mode so closely. The three digits (or letter followed by two digits) after the first two letters were essentially a sequence number, with (at first) a vestige of the valve-era convention that the first one or two digits would indicate the base (package) type in examples such as in this family of general-purpose transistors: ... where x may be: Pro Electron naming for transistors and Zener diodes has been widely taken up by semiconductor manufactures around the world. Pro Electron naming of integrated circuits, other than some special (e.g. television signal-processing) chips, did not greatly take hold (even in Europe). Other popular designation systems were used for many integrated circuits.

Differences between Pro Electron and earlier valve-naming conventions

Frequently used first letters in European active devices

Electron tubes

ECC81 / \ \__ last digit(s)=serial number / \ __ first digit(s)=base (3=8pin 8,18,80=Noval (B9A), 9=Mini 7-pin (B7G) / ___ one letter per valve unit in the tube: D=1.4v or less A=single-diode (low power) E=6.3v* B=double-diode (usually shared cathode, but not always) P=300mA C=triode U=100mA F=pentode (low power) L=pentode (high power) Y=Single-phase rectifier Z=Full-wave rectifier * Note: some 6.3 volt heater types have a split heater allowing series (12.6 volt; the default for Noval pins 4 to 5) or parallel (6.3 volt) operation.

Semiconductor diodes and transistors

The first letter gives the semiconductor type

(see above)

The second letter denotes the intended use

The serial number

Following these two letters is a 3- or 4-digit serial number (or another letter then digits), assigned by Pro Electron. It is not always merely a sequence number; there is sometimes information conveyed in the number:

Suffixes and version specifiers

Suffixes may be used, letters or perhaps blocks of digits delimited by "/" or "-" from the serial number, often without fixed meanings but some of the more common conventions are: Examples of suffixes and manufacturers' extensions to the basic sequence number include: Note: A BC546 might only be marked "C546" by some manufacturers, thus possibly creating confusion with JIS abbreviated markings, because a transistor marked "C546" might also be a 2SC546. Short summary of the most common semiconductor diode and transistor designations: BC549C / |--- ___ variant (A,B,C for transistors implies low, medium or high gain) / | ____ serial number (at least 3 digits or letter and 2 digits) / device type: A=Ge A=Signal diode B=Si C=LF low-power transistor D=LF Power transistor F=RF transistor (or FET) P=Photosensitive transistor etc. T=Triac or thyristor Y=Rectifier diode Z=Zener diode

Usage in the Eastern Bloc

Poland, Hungary, Romania, and Cuba mostly used Pro Electron designations for discrete semiconductors just like Western Europe. Starting in 1971, in Poland the letter "P" was inserted, e.g. BUY54 became BUYP54. Kombinat Mikroelektronik Erfurt (KME) in East Germany and Tesla (Czechoslovak company) used designations derived from the Pro Electron scheme. In particular, the first letter specifying the material differed while the second letter followed the table above (with the few exceptions for KME noted below). Examples: - Germanium power transistor from KME; - optoisolator from KME; KD503 - Silicon power transistor from Tesla; - LED from Tesla.

Integrated circuits

The integrated circuit designation consists of three letters, followed by a serial number of three to five digits. Initially, only three-digit serial numbers were allowed. For designations with a three-digit serial number the third initial letter had a defined meaning for digital integrated circuits (see below) and the operating temperature range was encoded in the last digit of the serial number. The specification was changed in 1973 to allow longer serial numbers. For designations with a serial number of more than three digits the third initial letter encodes the temperature range. Optionally, a version letter (A, B, ...) and / or a package designation can follow after the serial number.

Digital logic families

The combination of first letter and second letter is assigned to a specific manufacturer. FCH171 // \ __ serial number (including temperature range) // ___ H=gate ("Combinatorial circuit"), J=flip-flop, K=monostable, L=level shifter, Q=RAM, R=ROM, Y=miscellaneous etc. FC=DTL by Philips / Mullard FD=dynamic PMOS by Philips / Mullard FE=PMOS by Philips / Mullard FH=TTL by Philips (SUHL II series) FJ=TTL by Philips / Mullard (7400 series) FK=E2CL by Philips FL=TTL by Siemens (7400 series) FN=ECL by Telefunken FP=HTL by Telefunken FQ=DTL by SGS-ATES FS=SECL by Telefunken FY=ECL by Siemens FZ=HTL by Siemens GD=PMOS by Siemens (MEM1000 series) GH=ECL by Philips GJ=TTL by Mullard (74H00 series) GR=interface devices by Mullard (7500 series) GT=TTL by Mullard (74S00 series) Unfortunately the serial number does not specify the same type of gate in each family, e.g. while an FJH131 is a quadruple 2-input NAND gate (like the 7400), an FCH131 is a dual 4-input NAND gate, and an FLH131 is an 8-input NAND gate (equivalent to 7430). To lessen the confusion at least for the 7400 series, at some point manufacturers included the well-known 7400 series designation both in their literature and on the integrated circuits themselves.