diy-layout-creator/diylc/docs/plans/transistor-pinouts.md

Transistor Pinouts and Datasheet Models

Giving every transistor package a pinout, and applying a known part's pinout from a datasheet.

1. Goal

Builds on DIP IC Pin Names. A transistor whose pins are anonymous gives the netlist, the AI and the schematic view nothing to tell a base from a collector. The packages that extend AbstractTransistorPackage (TO-1, TO-92, TO-126, TO-220) already have a "Pinout" property, but users rarely set it: of 35 package transistors in the sample corpus, 6 have a pinout. A datasheet of the parts DIYers actually use (guitar pedals, effects, hi-fi, radio, synth) sets the pinout and the value in one step, from the toolbox or from the AI.

TO-3 was the one package without a pinout: a separate class with two numbered pins and no way to reach the case, which is the collector.

2. Design decisions

#	Decision	Choice	Rationale
T1	Datasheet row	group, part, pinout, e.g. BJT (NPN),2N3904,BJT_EBC. The pinout column is a TransistorPinout constant name	The enum already carries everything a part needs. Constant names are unambiguous and greppable; the display strings (E-B-C BJT) are not.
T2	Model identity	datasheetModelColumn = 1, datasheetCreationStepCount = 2 on every package, as on the ICs	The toolbox groups by family while the AI names the part.
T3	applyModel	Sets value and pinout only, implemented once in AbstractTransistorPackage (and in TransistorTO3, which does not extend it). Each package has a (String[] model) constructor	The datasheet says what the part is, not how it is drawn.
T4	Pin order	A pinout lists control points in order, and control point 0 is pin 1: for TO-92 facing the flat side, for TO-126 and TO-220 facing the printed front, legs down, left to right. Rows are written as the manufacturer's pin 1, 2, 3	Already the convention of the TO-92 and TO-220 @AiNotes, so existing projects keep their meaning.
T5	One package per datasheet	A part goes in the datasheet of the package it ships in. TransistorTO1 is the only metal can, so it also holds TO-18, TO-5, TO-39 and the germanium cans	Datasheets are per class.
T6	SPICE mapping	TransistorPinout.mapToSpiceNode places each letter in SPICE order (C B E, D G S); regulators keep their own order	Replaces a hand-written switch with fall-throughs that had no BJT_ECB case, so ECB parts went out in the wrong order. Shared by AbstractTransistorPackage and TransistorTO3.
T7	TO-3 case	A third control point at the centre of the mounting hole on the side the pins are offset towards. The pinout lists pin 1, pin 2, case (BJT_BEC for a 2N3055)	A wire or solder lug at the hole puts the collector into the netlist. Without it a TO-3 collector could never be connected.
T8	TO-3 compatibility	Old files hold a two-point controlPoints; getControlPoints() extends it lazily and places the case point from the two pins. TransistorTO3 keeps extending AbstractLabeledComponent	Moving it under AbstractTransistorPackage would change field types. Lazy migration is the established pattern.
T9	TO-3 display	New transistorDisplay field (TransistorDisplay), shown as "Display", read lazily from the deprecated display (Display) field	Adds the Pinout option the other packages have without changing a serialized field's type. All old Display values exist in TransistorDisplay.
T10	Pins over the body	Every package draws its pins after the body: AbstractTransistorPackage.drawPins for TO-1, TO-92, TO-126 and TO-220, its own loop in TransistorTO3. Round pins in the TO-92 colours (#00B2EE, border one shade darker), outline only in outline mode; folded TO-126/TO-220 leads use the same colours instead of METAL_COLOR. TO-3 pinout letters sit beside each pin and beside the case hole, towards the body centre	Bodies used to hide the pins at full alpha and tint them below it, so pin colour varied with the body, and the folded leads were grey. Now pins look the same on every package and show at any alpha, as on MultiwattIC.
T11	New pinout values	Added only when a sourced part needs them, inserted next to their family in the enum	Values are serialized by name, so order is free. Added: BJT_BEC (TO-3 transistors, MPSH10), BJT_CEB (BF199, BF494), REGULATOR_AIO (LM337T, LM317K), REGULATOR_IOG (TO-3 fixed regulators).

Explicitly out of scope

• TO-247, TO-3P, TO-264 packages (2SC5200, TIP3055, IRFP240, 2SK1058) - no package in DIYLC yet.
• SCRs, triacs and TL431-style references: their roles are not in TransistorPinout.
• SPICE export of regulators (getPrefix returns R, a resistor). Pre-existing, left as is.
• Translating datasheet group names, as for the ICs.

3. Changes

diylc-library

• TransistorPinout: mapToSpiceNode(int) (T6), BJT_BEC (T7).
• AbstractTransistorPackage: implements IDatasheetSupport, applyModel; mapToSpiceNode delegates to the enum; drawPins (T10).
• TransistorTO1, TransistorTO92, TransistorTO126, TransistorTO220: datasheet attributes on the descriptor, a model constructor, and pins drawn through drawPins after the body (T10).
• TransistorTO3: case point (T7, T8), pinout, ISpiceMapper, IDatasheetSupport, model constructor, transistorDisplay (T9), pins over the case and pinout letters (T10).
• datasheets/TransistorTO1.datasheet, TransistorTO3, TransistorTO92, TransistorTO126, TransistorTO220: rows per T1, each read from a manufacturer pin table or two independent sources.

Generated

• catalog_full.json regenerated (run ComponentCatalogGenerator from diylc-swing; with a hand-built classpath it reads the version as 5.0.0, so check that the version line matches the latest release in update.xml).
• diylc-library/src/test/resources/pinout-drivers.txt: TO-3 is driven by "Pinout".

4. Datasheet inventory

Groups: BJT (NPN), BJT (PNP), Darlington (NPN), Darlington (PNP), Germanium (NPN), Germanium (PNP), JFET (N), JFET (P), MOSFET (N), MOSFET (P), Regulator.

TransistorTO1.datasheet holds 31 parts, all BJT_EBC:

Group	Parts
BJT (NPN)	BC107, BC108, BC109, 2N2222A, 2N2369A, 2N2219A, 2N1613, 2N1711, 2N3053, 2N3866, BFY51
BJT (PNP)	BC177, BC178, BC179, 2N2907A, 2N2905A
Germanium (NPN)	AC127, AC176, AC187, 2N1308
Germanium (PNP)	AC126, AC128, AC188, OC44, OC45, OC71, OC75, OC76, OC81, 2N404, 2N1305

TO-1 sourcing and modelling notes:

• Read from Mullard/Valvo data-book scans (AC, OC), Central and Philips datasheets (silicon cans), and TI bulletin DL-S 1136 (2N1305/2N1308). 2N2219A, 2N2905A and BFY51 were seen only through search snippets of the Philips sheets - the weakest rows.
• Seen from the bottom, E-B-C run clockwise from the tab, so from above (DIYLC's view) they run counter-clockwise: control points 0, 1, 2 in the default orientation. The AC cans have B at the apex of the triangle, matching control point 1. No tab is drawn.
• The OC series are glass envelopes with in-line leads (wider B-C gap, red dot at the collector), not TO-1 cans; they are listed here because TO-1 is DIYLC's only small round package and the lead order is the same.
• On 2N1305/2N1308 the case is the base, not the collector.
• Left out, no manufacturer drawing or two agreeing sources: AC125, OC72, OC139/140, NKT275, 2N527, 2N388A, 2N2613, 2SB75, 2SB175, AC151, 2N5320. Soviet MP39-MP42 use a flanged can that is not TO-1-like. 2N4416 has four leads (S-D-G-case) and cannot fit.

TransistorTO92.datasheet bipolar rows, 68 parts:

Group	Pinout	Parts
BJT (NPN)	BJT_EBC	2N3904, 2N4401, PN2222A, 2N4124, 2N5088, 2N5089, 2N5210, 2N5551, MPSA06, MPSA18, MPSA42, MPS5179, S8050, S9013, S9014, S9018
BJT (NPN)	BJT_CBE	BC546-BC550, BC337, BC182, BC184, BC239, P2N2222A
BJT (NPN)	BJT_ECB	BC639, BC182L, BC184L, 2SC1815, 2SC945, 2SC2240, 2SC1845, KSC1845, 2SC2458
BJT (NPN)	BJT_CEB / BJT_BEC	BF199, BF494 / MPSH10
BJT (PNP)	BJT_EBC	2N3906, 2N4403, PN2907A, 2N4126, 2N5087, 2N5401, MPSA56, MPSA92, S8550, S9012, S9015, KSP2907A
BJT (PNP)	BJT_CBE	BC556-BC560, BC327, BC212, BC214
BJT (PNP)	BJT_ECB	BC640, 2SA1015, 2SA970, 2SA992, KSA992, KSP2907AC
Darlington (NPN) / (PNP)	BJT_EBC	MPSA13, MPSA14 / MPSA63, MPSA64

TO-92 sourcing notes:

• Philips/NXP (SOT54) and CDIL number TO-92 pins in reverse, from the right as seen facing the flat side; onsemi, Central, Toshiba, NEC, UTC and MCC number from the left. Philips "1 emitter 2 base 3 collector" on a BC547 is physically C-B-E. Copying Philips or CDIL numbers literally is the usual source of wrong pinouts online; rows here are the physical order. onsemi CASE 29 style 1 = EBC, style 14 = ECB, style 17 = CBE.
• Same name, different pinout, each listed under its full name: BC182L/BC184L (ECB) vs BC182/BC184 (CBE); P2N2222A (CBE) vs PN2222A (EBC); KSP2907AC (ECB) vs KSP2907A (EBC); MPS5179 (EBC) vs PN5179 (BEC, not listed). onsemi's MPSA92 package page prints style 14, contradicting its own symbol and Central (EBC).
• 2N5179 itself is TO-72 only. 2SC2458 is Toshiba's smaller 2-4E1A body at 1.27 mm pitch.
• Weakest rows: BF494 (one Philips sheet plus a search quote), 2SC1845 and 2SA992 (second-source and NEC text copies), 2N4124/2N4126 (Central only), BC239 (CDIL only).
• Left out: BC212L/BC214L (CDIL table is an image; inferred only), 2SC828 (second source only), PN5179, KTC3198/KTA1266 (mirror previews only), 8050S/8550S (ECB at UTC; 8550S not read).

TransistorTO126.datasheet holds 22 parts, all BJT_ECB: BD135/137/139, BD136/138/140, BD237/238, MJE340/350, MJE170/180, 2SC3423/2SA1360, KSC3503/KSA1381, 2SD669A/2SB649A, BF469/470, and the BD681/682 darlingtons.

TransistorTO220.datasheet holds 67 parts:

Group	Parts	Pinout
BJT (NPN) / (PNP)	TIP29C-TIP42C, MJE3055T/2955T, MJE15028-15033, BD243C/244C, BD911/912	BJT_BCE
Darlington (NPN) / (PNP)	TIP120-122, TIP125-127	BJT_BCE
MOSFET (N) / (P)	IRF510, IRF520, IRF530, IRF540N, IRF610, IRF640, IRF840, IRFZ44N, IRLZ44N, IRF3205, FQP30N06L; IRF9530, IRF9540N, IRF9610, IRF9640	MOSFET_GDS
Regulator (+)	7805-7824 and LM2940CT-5.0/-12	REGULATOR_IGO
Regulator (+)	LM317T, LM338T, LM350T, LM1084/1085/1086-ADJ, LM1117T-ADJ, LD1117V	REGULATOR_AOI
Regulator (+)	LM1086-3.3/-5.0, LM1117T-3.3/-5.0, LD1117V33/V50	REGULATOR_GOI
Regulator (-)	7905, 7912, 7915 / LM337T	REGULATOR_GIO / REGULATOR_AIO

TransistorTO3.datasheet holds 27 parts; the pinout's third letter is the case:

Group	Parts	Pinout
BJT (NPN) / (PNP)	2N3055, 2N3442, 2N3773, MJ15003, MJ15015, MJ15022, MJ15024; MJ2955, 2N6609, MJ15004, MJ15016, MJ15023, MJ15025	BJT_BEC
Darlington (NPN) / (PNP)	MJ11016, MJ11032; MJ11015, MJ11033	BJT_BEC
MOSFET (N)	IRF150	MOSFET_GSD
Regulator (+)	LM317K, LM338K, LM350K	REGULATOR_AIO
Regulator (+)	LM309K, LM323K, LM340K-5.0/-12/-15	REGULATOR_IOG
Regulator (-)	LM337K	REGULATOR_AOI

Power package sourcing notes:

• Read mostly from onsemi (TO-225 style 1, TO-220 CASE 221A styles 1 and 5, TO-3 CASE 1-07 style 1) and TI regulator pin tables. Rows taken from a family rule rather than the part's own sheet: BD136/138/140, MJE170/180, BD682, BD238, 2SA1360, BF469, TIP29C/30C, BD911/912, the IRF parts other than IRF510/IRF540N, MJ15015/16, 2N6609, LM350K. IRF150 is from two search snippets.
• TO-3 geometry from onsemi CASE 1-07 (with ST and Central agreeing): pins 10.92 mm apart on a line square to the hole axis, about 1.8 mm off centre towards the nearer hole. Seen from above with the holes left and right and the pins left of centre, pin 1 is the upper pin - control point 0 in the default orientation, so the TO-3 geometry needed no change. ST numbers TO-3 pins the other way round (its LM137 "1 = Output"); the rows follow onsemi/TI/National, whose pin functions match ST's physically.
• LM309K/LM323K/LM340K: TI and National draw the pin positions but give no pin numbers; numbers were assigned from the physical position. The weakest TO-3 rows.
• Left out: TIP142/147 (SOT-93/TO-247 at onsemi), LM2941 (5 leads), ECX10N20/P20 (TO-247), the lateral 2SK134/135 and 2SJ49/50 (case is probably source, not drain - no Hitachi sheet found), and TO-3 79xx (unsourced).

TransistorTO92.datasheet FET and regulator rows, 41 parts:

Group	Pinout	Parts
JFET (N)	JFET_DSG	J201, J202, J111, J112, J113, J310, 2N5457, 2N5458, 2N5459, 2N5484, 2N5485, 2N5486, PN4416, MPF102, BF245A/B/C
JFET (N)	JFET_SGD / JFET_GSD / JFET_DGS	2N3819 / BF256B / 2SK170, LSK170
JFET (P)	JFET_DGS / JFET_SDG	J174, J175, J176, 2N3820 / 2N5460
MOSFET (N)	MOSFET_SGD / MOSFET_DGS	2N7000, LND150 / BS170
Regulator (+)	REGULATOR_OGI	78L05, 78L09, 78L12, 78L15, LP2950-5.0, LM2936Z-5.0
Regulator (+)	REGULATOR_AOI / REGULATOR_IOA	LM317LZ / LR8
Regulator (-)	REGULATOR_GIO / REGULATOR_AOI	79L05, 79L12, 79L15 / LM337LZ

TO-92 FET and regulator notes:

• TI's TO-92 outline (LP0003A) and its TL431, LM317L and LM385 tables number from the right, like Philips; the parts are physically the same as onsemi's. Rows are the physical order.
• JFET makers often differ by a drain/source swap (InterFET lists J201, J310, 2N5457, 2N5484-86 and PN4416 as S-D-G; Fairchild, Linear Systems, Central and onsemi as D-S-G). The gate position, which is what matters, agrees, and the rows follow the majority. 2N3819: S-G-D at onsemi, InterFET and Vishay, D-G-S at Central. J174/J175: D-G-S at Linear Systems, S-G-D at InterFET.
• BF245 is a real conflict: Philips (the original, the classic European part) is D-S-G, onsemi is G-S-D - the gate at opposite ends. Both are discontinued; the rows follow Philips. A layout built around an onsemi BF245 needs JFET_GSD.
• BS170 follows onsemi's TO-92 (D-G-S); Diodes' "TO-92 compatible" E-Line BS170P is marked on the rounded face and is S-G-D seen from the flat side.
• LND150 is from Microchip's numbered pin table. LR8 (IN, OUT, ADJ - not the LM317 order) is from the same Supertex 3D drawing, read with the LND150 as calibration; the weakest row in the file. 2N5459 and 2N3820 rest on one sheet each.
• Left out: MPF4393, 2SK30A, 2SK117, 2SJ74, LSJ74, VN10KM (unsourced); BS250 and VP2106 (drawing only, not requested); 79L09 (not a listed voltage); TL431, LM385 and LM336 (roles are not in TransistorPinout).

5. Tests

• TransistorPinoutTest: SPICE order per type, including the BJT_ECB fix; every value is a permutation of its type's roles.
• TransistorTO3Test: case point sits in a mounting hole in every orientation; a two-point instance gains the case point where a new one has it; node names follow the pinout; display is read from the legacy field.
• TransistorDatasheetTest: across all five datasheets, every row has three columns, parses and applies; part numbers unique per package; findSeries finds a part and not a group.

6. Verification

• Done: mvn -q test over the whole reactor passes (core 227, library 504, swing 29). pinout-drivers.txt was updated because TO-3 terminals are now driven by "Pinout".
• Done: TO-3 rendered headlessly in all four orientations at 100 % and 50 % alpha with Display = Pinout - pins show over the case, the case point sits in the pin-side hole, letters beside each. All five packages rendered standing, folded and at 50 % alpha: pins on top in one colour.
• Open: the regression suite. Every project with a transistor package now renders differently (pins visible over the body, blue folded leads), TO-3 projects carry a third, normally unconnected, node, and ECB parts change SPICE order. Reference outputs are regenerated only after the diffs are confirmed to be exactly that.

7. Phases

1. Pinout everywhere: done (T6 to T11, TransistorPinoutTest, TransistorTO3Test, @AiNotes on pin order for TO-1, TO-126 and TO-3).
2. Datasheet support: done (T1 to T3, TransistorDatasheetTest).
3. Library: done - 256 parts: TO-92 109, TO-220 67, TO-1 31, TO-3 27, TO-126 22. catalog_full.json regenerated. Further parts on request, each read from a manufacturer pin table first.
4. Next: the regression run of §6; then, if wanted, the TO-247/TO-3P package (2SC5200/2SA1943, TIP3055/2955, IRFP240/9240, lateral MOSFETs) and a role set for shunt references (TL431).