Fairchild Semiconductor Manufacturer Skill

Company Overview

Fairchild Semiconductor was a pioneering semiconductor company founded in 1957, known for inventing the planar process and helping create Silicon Valley. The company was acquired by ON Semiconductor in 2016. Fairchild was particularly renowned for:

• Power MOSFETs: FQP, FQD, FQU, FQL, FDB, FDA series
• Small signal transistors: 2N series, BS series
• Power management: Voltage regulators
• Discrete semiconductors: Diodes, transistors

Note: Many Fairchild part numbers are still in production under ON Semiconductor branding. The FairchildHandler in this library handles the legacy Fairchild nomenclature.

MPN Structure by Product Family

MOSFETs - FQP/FQD/FQU Series (Main Power MOSFETs)

FQ[PKG][CURRENT][CHANNEL][VOLTAGE][SUFFIX]
 |   |     |        |        |       |
 |   |     |        |        |       +-- Optional: L=Logic level
 |   |     |        |        +-- Voltage / 10 (e.g., 06=60V, 10=100V, 20=200V)
 |   |     |        +-- N=N-channel, P=P-channel
 |   |     +-- Current rating in Amps
 |   +-- Package: P=TO-220, D=DPAK, U=IPAK
 +-- FQ = Fairchild QFET series

Package Codes in FQ Series:

Examples:

• FQP30N06

  = TO-220, 30A, N-channel, 60V

• FQP50N06L

  = TO-220, 50A, N-channel, 60V, Logic Level

• FQP27P06

  = TO-220, 27A, P-channel, 60V

• FQD13N10

  = DPAK, 13A, N-channel, 100V

• FQU11P06

  = IPAK, 11A, P-channel, 60V

MOSFETs - FDS Series (SO-8 Package)

FDS[CODE][CHANNEL]
 |    |      |
 |    |      +-- N implied for N-channel, P for P-channel
 |    +-- Device code (performance/voltage identifier)
 +-- FDS = Fairchild Discrete SO-8

Examples:

• FDS6680A

  = N-channel, SO-8, 30V, enhanced

• FDS9926A

  = Dual N-channel, SO-8

• FDS4141P

  = P-channel, SO-8

MOSFETs - FDB/FDA Series (PowerTrench Technology)

FD[TYPE][CODE]
 |   |     |
 |   |     +-- Device code (identifies voltage/current class)
 |   +-- B=D2PAK, A=Complementary pair
 +-- FD = Fairchild PowerTrench

Examples:

• FDB3632

  = D2PAK, PowerTrench, 100V, 73A

• FDB045AN06

  = D2PAK, N-channel, 60V, 80A

• FDA24N40F

  = Complementary pair

MOSFETs - FQL Series (Logic Level)

FQL[CODE]
 |    |
 |    +-- Device code
 +-- FQL = Fairchild QFET Logic Level

The FQL series features lower gate threshold voltage (~2.5V max Vgs) for direct logic-level drive.

Examples:

• FQL40N50

  = Logic level, 40A, 500V

Small Signal MOSFETs - 2N7xxx Series

2N7[CODE][SUFFIX]
 |    |      |
 |    |      +-- Grade suffix (A, B, etc.)
 |    +-- JEDEC registration number
 +-- 2N = JEDEC transistor prefix

Examples:

• 2N7000

  = N-channel, TO-92, 60V, 200mA

• 2N7002

  = N-channel, SOT-23, 60V, 115mA

Small Signal MOSFETs - BS Series

BS[CODE][SUFFIX]
 |   |      |
 |   |      +-- Package/variant suffix
 |   +-- Device code
 +-- BS = Small signal MOSFET

Examples:

• BS170

  = N-channel, TO-92, 60V, 500mA

• BSS138

  = N-channel, SOT-23, 50V, 200mA

Supported Component Types

From

FairchildHandler.getSupportedTypes()

MOSFET

TRANSISTOR

DIODE

VOLTAGE_REGULATOR

Note: The handler uses standard

ComponentType

MOSFET_FAIRCHILD

Package Codes

Through-Hole Packages

Surface Mount Packages

Package Extraction from Prefix

The handler extracts package type from the MPN prefix:

Series Extraction Rules

The handler extracts series using regex patterns:

FQP[digits][N/P][digits]

FQD[digits][N/P][digits]

FQU[digits][N/P][digits]

FDS[digits]

FQL[digits]

2N7[digits]

Series Extraction Code Logic:

// FQP, FQD, FQU series - extract up to N/P + voltage
"FQP30N06L" -> regex "([A-Z0-9]+[NP][0-9]+).*" -> "FQP30N06"

// FDS series - extract prefix + digits only
"FDS6680A" -> regex "(FDS[0-9]+).*" -> "FDS6680"

// FQL series - extract prefix + digits
"FQL40N50" -> regex "(FQL[0-9]+).*" -> "FQL40"

// 2N7 series - extract full JEDEC number
"2N7000" -> regex "(2N7[0-9]+).*" -> "2N7000"

Pattern Matching

Registered Patterns in

initializePatterns()

N-Channel MOSFETs:

^FQP[0-9].*N[0-9].*

^FQD[0-9].*N[0-9].*

^FQU[0-9].*N[0-9].*

^FDS[0-9].*

P-Channel MOSFETs:

^FQP[0-9].*P[0-9].*

^FQD[0-9].*P[0-9].*

^FQU[0-9].*P[0-9].*

^FDS[0-9].*P.*

Other MOSFET Families:

^FQL[0-9].*

^2N7[0-9].*

^BS[0-9].*

^FDB[0-9].*

^FDA[0-9].*

Official Replacement Logic

The

isOfficialReplacement()

Same Series Check

// Same series + same package = direct replacement
FQP30N06 <-> FQP30N06L (same series, same package)

// Same series + compatible package = replacement
FQP30N06 <-> FQD30N06 (same series, compatible packages)

Compatible Packages

• TO-220 variants (TO-220, TO-220F) are compatible
• DPAK and D2PAK are often compatible
• SOT-223 and DPAK can be compatible

Known Cross-References

FQP30N06 <-> IRF530 (equivalent N-channel 60V MOSFETs)

Example MPNs with Full Decoding

FQP50N06L

FQP50N06L
│  │  │ │└── L = Logic Level (low Vgs threshold)
│  │  │ └── 06 = 60V (06 x 10)
│  │  └── N = N-channel
│  └── 50 = 50A drain current
└── FQP = TO-220 package

Specs: TO-220, N-channel, 60V, 50A, Logic Level

FQD13N10

FQD13N10
│  │  │ │
│  │  │ └── 10 = 100V (10 x 10)
│  │  └── N = N-channel
│  └── 13 = 13A drain current
└── FQD = DPAK package

Specs: DPAK, N-channel, 100V, 13A

FQP27P06

FQP27P06
│  │  │ │
│  │  │ └── 06 = 60V
│  │  └── P = P-channel
│  └── 27 = 27A drain current
└── FQP = TO-220 package

Specs: TO-220, P-channel, 60V, 27A

FDS6680A

FDS6680A
│  │    │
│  │    └── A = Improved version/grade
│  └── 6680 = Device code (identifies 30V, 10.5A specs)
└── FDS = SO-8 package

Specs: SO-8, N-channel, 30V, 10.5A

2N7000

2N7000
│ │   │
│ │   └── 000 = JEDEC sequence number
│ └── 7 = Series identifier (70xx = small signal MOSFETs)
└── 2N = JEDEC transistor prefix

Specs: TO-92, N-channel enhancement MOSFET, 60V, 200mA

Common Part Numbers Reference

Popular N-Channel MOSFETs

Popular P-Channel MOSFETs

PowerTrench Series

Handler Implementation Notes

Quirks in Current Implementation

1. STM32 code in extractPackageCode(): Lines 115-126 contain STM32-specific extraction logic that appears to be copy-paste error from STHandler. This code path is never reached for Fairchild MPNs.

2. HashSet in getSupportedTypes(): Uses mutable

   HashSet

   instead of immutable

   Set.of()

   . Should be updated for consistency with other handlers.

3. Limited transistor/diode patterns: The handler only registers MOSFET patterns in

   initializePatterns()

   . No patterns for transistors or diodes despite declaring them in

   getSupportedTypes()

   .

4. Cross-handler pattern matching: Uses

   patterns.matchesForCurrentHandler()

   to avoid false matches from other handlers' patterns (good practice).

Recommended Improvements

// Change getSupportedTypes() from HashSet to Set.of()
@Override
public Set<ComponentType> getSupportedTypes() {
    return Set.of(
        ComponentType.MOSFET,
        ComponentType.TRANSISTOR,
        ComponentType.DIODE,
        ComponentType.VOLTAGE_REGULATOR
    );
}

// Add missing transistor patterns
registry.addPattern(ComponentType.TRANSISTOR, "^2N[2-6][0-9]{3}.*");
registry.addPattern(ComponentType.TRANSISTOR, "^BC[0-9]{3}.*");

// Add missing diode patterns
registry.addPattern(ComponentType.DIODE, "^1N[0-9]{4}.*");

Related Files

• Handler:

  manufacturers/FairchildHandler.java

• ON Semiconductor handler:

  manufacturers/OnSemiHandler.java

  (parent company)
• Component types: Uses standard

  MOSFET

  ,

  TRANSISTOR

  ,

  DIODE

  ,

  VOLTAGE_REGULATOR

Cross-Reference to ON Semiconductor

Since Fairchild was acquired by ON Semiconductor in 2016, many part number series overlap:

For newer designs, check ON Semiconductor's current product lineup as some Fairchild parts may be NRFND or obsolete.

Learnings & Edge Cases

• Logic Level suffix: "L" at end of MPN indicates logic-level gate threshold (~2.5V Vgs max), critical for 3.3V/5V logic drive
• Voltage encoding: Voltage divided by 10 in FQ series (06=60V, 10=100V, 20=200V)
• Current in part number: Current rating directly encoded (FQP30N06 = 30A)
• Channel polarity: N/P letter in middle of MPN determines N-channel vs P-channel
• SO-8 code differences: FDS series numbers encode specs, not straightforward voltage/current decode
• Package from prefix: FQP=TO-220, FQD=DPAK, FQU=IPAK is reliable extraction method
• Cross-reference with IRF: FQP30N06 is often cross-referenced with IRF530 (both 60V N-channel)
• STM32 code anomaly: extractPackageCode() has unreachable STM32-specific code (copy-paste artifact)
• PowerTrench branding: FDB/FDA series use Fairchild's proprietary PowerTrench technology for lower Rds(on)