HP diode coding
SOD-80 (Melf) diodes
Coloured SOD-123/323 diodes
SMD Ceramic Capacitors
The Surface Mount Device Code Book
© R P Blackwell GM4PMK
A marsport publication!
SMD devices are, by their very nature, too small
to carry conventional semiconductor type numbers. Instead, a somewhat arbitrary
coding system has grown up, where the device package carries a simple two- or
three-character ID code. Identifying the manufacturers' type number of an SMD
device from the package code can be a difficult task, involving combing through
many different databooks. This HTML book is designed to provide an easy means
of device identification. It lists over 3,500 device codes in alphabetical order,
together with type numbers, device characteristics or equivalents and pinout
information. Sometimes I'm asked to put IC information in the codebook. There
is some information about ICs - but first and foremost the codebook is
intended for discrete devices. Some ICs have been included, usually these are
3/4 pin devices or RF circuits I'm interested in.
The home of GM4PMK's SMD codebook is here - and
it's only here you'll get the most up-to-date information as it's updated often........
There are a number of other copies of this codebook on the Net, of varying ages.
Some are translations with my permission, some are just straight rip-offs. None
of them will be as up to date as the original.
How to use the SMD Codebook
To identify a particular SMD device, first identify
the package style and note the ID code printed on the device. Now look up the
code in the alphanumeric listing which forms the main part of this book by clicking
on the first character shown in the left-hand frame. A scrollable page of data
will appear in the main frame.
Unfortunately, each device code is not necessarily unique. For example a device
coded 1A might be either a BC846A or a FMMT3904. Even the same manufacturer
may use the same code for different devices! If there is more than one entry,
use the package style to differentiate between devices with the same ID code.
Identifying the package is not always easy - measuring the package dimensions
may help; and the codebook has some information about these.
This compilation has been collected from manufacturers'
data and other sources of SMD device ID codes, pinout and leaded device equivalent
information. The entries under the Manufacturer column are not intended to be
comprehensive; rather they are intended to provide help on locating sources
of more detailed information if you require it.
When you have looked up a device, the Base letter
will guide you to a pin-out diagram. Note that some bases have marks to show
the correct orientations, on others, one or more 'pins' may be a different size
or shape. Some packages have nothing at all - in that case the device is shown
such that the ID code is the right way up.
ID Code Variations
Many manufacturers use an extra letter as their
own identification code, or to show the country of manufacture. If the device is from Philips/NXP it will sometimes have
a lower case 'p' or sometimes 't' added to the code; some manufacturers have used a symbol
or lower case letter to indicate the country of manufacture. These have been
ignored in the alphabetical ordering. For example 'Z-S' and 'ZtS ' are both 2PC4081Q devices made by Philips; the first made in Hong Kong and
the second in Malaysia; they appear in the codebook classified under ZS. Siemens
devices usually have a lower case 's'. Note that these prefix/suffix letters are always shown in lower case.
To save table space, often only ONE variant from each manufacturer will appear in the table.
Philips/NXP have used -, t, p and w to An example, if you have a device with the code 1At, look up 1Ap. Many recent Motorola devices have a small superscript
letter after the device code, such as SAC.
This smaller letter is merely a month of manufacture code. Many devices from Rohm Semiconductors which start
with G have direct equivalents found in the rest of the code. For example GD1 is the same as D1 which is a BCW31.
Note that p6A (for example) is different from 6Ap. The
position of the 'p' is important! In this case, p6A is a jfet, and 6Ap a bipolar
You'll find both of these in the '6' page though - in
other words these lower case prefixes or suffixes are ignored for indexing purposes,
but critical to identifying the device.
Some devices have a single coloured letter (usually
on extremely small diode packages). Colour, if significant, is shown in small
type after the code letter.
An 'L' or 'W' suffix usually indicates a low-profile
package, such as an SOT323 or SC70.
A separate letter number group, often smaller and/or in a different orientation, is often used as a date code. To assist in identification, this is sometimes entered in the tables as x (lower case) as in '4Px' - device code 4P with a date code.
Reverse joggle devices do present a few problems.
They often have an 'R' in the type number. A reverse package is one
where the lead have been bent up instead of down. So it's a mirror image of
a conventional device. Identification is usually possible from the code number,
but some manufacturers use the same code. In these cases, it's a case of looking
at the device with a magnifying glass. The leads of most normal packages come
out closer to the circuit board side of the device; conversely a reverse joggle
package will have them coming out closer to the 'top' of the device.
Sometimes a series of devices, derived from the
same die, have related type (not code) numbers. Often an 'R' will indicate
a reverse joggle package, and/or a 'W' indicate a smaller package variant,
such as SOT343. Sometimes similarities are also found in the code numbers. For
example '67' is the code for a BFP67 (SOT143 package) , and '67R'
is the code for the reverse joggle variant BFP67R (SOT143R), while 'W67'
is the code for a SOT343 package version.
Leaded equivalent device and information
Where possible, the listing gives the part number
of a conventional wire-leaded device with equivalent characteristics. If the
leaded device is well-known then no more information is given. If the device
is less common, some additional information will sometimes be given. Where no
exact leaded equivalent exists, a brief device description is given, which may
be sufficient to allow substitution with another device.
When describing device characteristics, some terms
are implied from the type of device. For example, a voltage specified for a
rectifier diode is usually the maximum PIV (peak inverse voltage) of the diode,
but for a zener diode the operating (zener voltage) will be given. Normally,
where a voltage, current or power is specified, these will be limiting values.
For example, a device specified as npn 20V 0.1A 1W is a NPN transistor with
a Vce (max) of 20V, maximum collector current of 100mA and a maximum total power
dissipation of 1W. Some of the transistors are types with integrated resistors;
in the list, a base resistor means a resistor connected in series with the base.
When two resistor values are given, the first is the series base resistor, and
the second the resistor between base and emitter.
Digital Transistors (dtr)
These are transistors with built-in resistors,
also called 'prebiased transistors'. The Codebook uses 'dtr' as it's shorter...
Some have one resistor between base and emitter, others in series with the base
lead. Many others have both. To keep things simple, the series resistor is called
R1 and the base emitter resistor is called R2. If both are present, then two
values are given, R1 first. So 4k7 + 10k means that R1 (the base resistor) is
4k7 and R2 (the resistor between base and emitter) is 10k.
The SMD Codebook is © R P Blackwell.