The Full Part Number of Component is Important when Engineers make a BOM List.
When purchasers purchase the components according to the BoM list which made by the Engineers,found that the components suppliers often need to ask the full part number, otherwise they will don,t know which one should be supply to you. In serious cases, the components you purchased can,t work at all. Why happened this? The problem is that many engineers with insufficient experience have not written the full part number in the BoM. The following example shows what the complete part number is.
The full part number of component includes the main body model number, prefix and suffix number . Most of Engineers only cares about the prefix and the body model, but ignores the suffix, and even a few engineers will ignore the prefix. Of course, not all devices must have a prefix and suffix, but as long as the device has the prefix and suffix number, it cannot be ignored.
The prefix number of a component is generally means a large series of devices. For example, the 74LS series in logic ICs represents low-power Schottky logic ICs, the 74ASL series represents advanced low-power Schottky logic ICs, and the 74ASL series has better performance than the 74LS series. One more example, the 2N5551 triode and the MMBT5551 triode are packaged differently, one is plug-in (TO-92) and the other is patch (SOT-23). If Engineer only write 5551 transistors on the BOM, the purchaser certainly don’t know which one is the right one.
The useful of suffix
1.Distinguishing the details of performance:
For example, the MAXIM’s reset chip MAX706, it is also 706, but there are several threshold voltages, such as the threshold voltage of the MAX706S is 2.93V, and the threshold voltage of the MAX706T is 3.08V, here the suffix “S” and “T” represents a different threshold voltage.
2.Distinguish the level and operating temperature of component:
For example, TI’s reference voltage chip TL431, TL431C represents the operating temperature of the device is 0 degrees to 70 degrees (civil grade), TL431I represents the operating temperature of the device is -40 degrees to 85 degrees (industrial grade), which suffix “C” and “I” stands for different working temperatures.
3.Distinguish the package form:
For example, TI’s reference voltage chip TL431, TL431CP represents the PDIP package, TL431CD represents the SOIC package, where the suffixes “P” and “D” represent different packages (“C” stands for temperature, as explained above).
4. Distinguish packaging:
For example, TI’s reference voltage chip TL431 CD, if required to be purchased by disk (2500PCS/disk), must be ordered according to the model number of TL431 CDR. The suffix “R” here stands for disk loading. Otherwise, press the TL431 CD to place an order, and the material that you bought may be a tube (75PCS/tube).
5.Distinguish lead and lead-free:
For example, ON company’s comparator chip LM393D (“D” means SOIC package), if you want to use lead-free models, you must order by LM393DG, the suffix “G” here means lead-free models, without this suffix is means with lead.
The suffix may have other special uses. In short, the suffix information cannot be omitted, otherwise the components your purchaser purchased may not the one you want.
The prefixes and suffixes are difference from different companies,so needs to refer to the actual situation of the manufacturer.
