Root/
| 1 | *** This is an older draft of the concept - differs sometimes from the way |
| 2 | things are done in gta02-core. *** |
| 3 | |
| 4 | |
| 5 | BOM matching |
| 6 | ============ |
| 7 | |
| 8 | BOMs are matched with inventories in the following way: |
| 9 | |
| 10 | - a .lst file with the BOM is generated by KiCad |
| 11 | |
| 12 | - using a ruleset, component characteristics are translated to a |
| 13 | canonical format and default values may be used for unspecified |
| 14 | characteristics |
| 15 | |
| 16 | - part catalogs are searched for matches with the canonical component |
| 17 | descriptions. This yields a list of supplier-specific part numbers |
| 18 | for each component. |
| 19 | |
| 20 | Parts can be characterized by either specifying their properties or |
| 21 | by equating them to another part. E.g., a Digi-Key part may be |
| 22 | defined as an NXP part which in turn is equivalent to a TI part. |
| 23 | |
| 24 | - this list is then matched against inventories, using a suitable |
| 25 | optimization strategy (e.g., prioritize inventories and try to |
| 26 | pick as many suitable components as possible higher priority ones |
| 27 | before moving to lower priority ones) |
| 28 | |
| 29 | E.g., local stock could be the first-level inventory, followed by |
| 30 | more distant warehouses, followed by distributors, followed by |
| 31 | manufacturers. |
| 32 | |
| 33 | Inventories could also include pricing information. |
| 34 | |
| 35 | - TBD: it would be good if parameters gathered in the matching process |
| 36 | could be fed back into KiCad (as some sort of annotations, similar |
| 37 | to the expanded view of schematic symbols), such that under-specifed |
| 38 | parts yielding mismatches can be spotted by manual review. |
| 39 | |
| 40 | |
| 41 | Catalog |
| 42 | ======= |
| 43 | |
| 44 | A catalog contains part characteristics and the reference number(s) |
| 45 | assigned to them. |
| 46 | |
| 47 | |
| 48 | Basic syntax |
| 49 | ------------ |
| 50 | |
| 51 | Catalog entries consist of "words" in the sense that each word does |
| 52 | not contain any whitespace and words are separated from each other by |
| 53 | whitespace. Whitespace can be included in a word if it is enclosed in |
| 54 | double quotes. |
| 55 | |
| 56 | Each entry begins in the first column of a line. If an entry needs |
| 57 | more than one line, the words on the continuation line(s) must be |
| 58 | indented by whitespace. |
| 59 | |
| 60 | Trailing whitespace is ignored, and so are comments beginning with a |
| 61 | hash mark. Blank lines end any entry and are also ignored. |
| 62 | |
| 63 | Each catalog entry begins with the part number followed by a part type |
| 64 | designator. |
| 65 | |
| 66 | Characteristics have the form <field>=<value>, where |
| 67 | the fields follow the pattern outlined below. The value is some |
| 68 | description of the value of that characteristic, typically a number |
| 69 | and a unit (e.g., 4.7uF) or a name (e.g., X5R). |
| 70 | |
| 71 | Numbers use a decimal point where necessary. Mantissas are normalized |
| 72 | such that they fall into the range 1 <= n < 1000. E.g., instead of |
| 73 | 0.1uF, write 100nF. There is no space between number and unit. The |
| 74 | Omega of Ohm is written as "R". |
| 75 | |
| 76 | |
| 77 | Fields |
| 78 | ------ |
| 79 | |
| 80 | Each |
| 81 | |
| 82 | General fields |
| 83 | - - - - - - - |
| 84 | |
| 85 | FP Footprint |
| 86 | H Height (overrides any height implied by footprint) |
| 87 | TOL Tolerance, with percent sign. Split tolerances are indicated as n/m% |
| 88 | DSC Free-format description |
| 89 | |
| 90 | |
| 91 | Resistors |
| 92 | - - - - - |
| 93 | |
| 94 | RES Part type designator |
| 95 | R Resistance, with unit |
| 96 | P Maximum power dissipation |
| 97 | V Maximum volatage |
| 98 | |
| 99 | |
| 100 | Capacitors |
| 101 | - - - - - |
| 102 | |
| 103 | CAP Part type designator |
| 104 | C Capacitance, with unit |
| 105 | M Material, e.g., TANT, NP0, X5R, etc. |
| 106 | V Maximum voltage |
| 107 | ESR ESR, with unit |
| 108 | |
| 109 | |
| 110 | Inductors |
| 111 | -- - - - |
| 112 | |
| 113 | Diodes |
| 114 | - - - |
| 115 | |
| 116 | DIODE Regular diode |
| 117 | STKY Schottky diode |
| 118 | |
| 119 | Vf Maximum forward voltage |
| 120 | Vr Maximum reverse voltage |
| 121 | If Maximum forward current |
| 122 | Ir Maximum reverse current |
| 123 | C Capacitance |
| 124 | |
| 125 | LED Ligh-emitting diode |
| 126 | |
| 127 | COL Color, multiple colors are separated by /, e.g., blue/red |
| 128 | ARRAY If multiple diodes form an array, this parameter describes |
| 129 | its structure: CA = common anode, CC = common cathode, |
| 130 | SEQ = tap-A-C-tap-A-C-tap sequence |
| 131 | |
| 132 | ZENER Zener diode |
| 133 | |
| 134 | Vz Zener voltage |
| 135 | |
| 136 | TVS Transient voltage suppressor |
| 137 | |
| 138 | Vac Working voltage, AC |
| 139 | Vdc Working voltage, DC |
| 140 | E Energy |
| 141 |
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