BJTs
Bipolar Junction Transistors (BJTs) are current-controlled devices used for signal amplification, switching, and voltage regulation in analog circuits, audio amplifiers, and legacy digital logic. Available in NPN and PNP configurations from Nexperia, onsemi, Vishay, Diodes Incorporated, and STMicroelectronics with parametric selection by collector-emitter voltage (VCEO), collector current (IC), gain (hFE), transition frequency (fT), and package.
Product Series & Base Models
481 model families directly associated with BJTs. Browse the full catalog with search and filters.
Browse BJTs Products
| PART NUMBER | MANUFACTURER | DESCRIPTION | STOCK | QTY / ACTION |
|---|---|---|---|---|
| BC817-40-AU_R1_000A1 | Panjit | Small Signal Bipolar Transistor, 0.5A I(C), 45V V(BR)CEO, 1-Element, NPN, Silicon | 188,024 | |
| BC807-25,215 | Nexperia | Single Bipolar Transistor, PNP, 45 V, 500 mA, 345 mW, SOT-23 (TO-236AB), 3 Pins, Surface Mount | 1,867,698 | |
| BC807-16LT1G | onsemi | Bipolar (BJT) Single Transistor, PNP, 45 V, 500 mA, 225 mW, SOT-23, Surface Mount | 3,247,207 | |
| 2SC5566-TD-E | onsemi | Bipolar Transistor, 50V, 4A, Low VCE(sat), (PNP)NPN Single PCP | 3,469,680 | |
| 2N4403BU | onsemi | Small Signal Bipolar Transistor, 0.6A I(C), 40V V(BR)CEO, 1-Element, PNP, Silicon, TO-92 | 963,290 | |
| 2N4401BU | onsemi | Bipolar (BJT) Single Transistor, NPN, 40 V, 600 mA, 625 mW, TO-92, Through Hole | 1,183,622 | |
| 2N2222A | STMicroelectronics | Bulk Through Hole Switch Single Bipolar (BJT) Transistor 100 @ 150mA 10V 10nA ICBO 500mW 300MHz | 43,763 | |
| UMZ1NT1G | onsemi | NPN/PNP BJT Transistor, 50V, 200mA, 114MHz, SC-88/SC70-6 | 864,000 | |
| UMC5NT2G | onsemi | Complementary Bipolar Digital Transistor (BRT), SC-88A (SC-70-5 / SOT-353), 3000-REEL | 810,000 | |
| UMC5NT1G | onsemi | Complementary Bipolar Digital Transistor (BRT), SC-88A (SC-70-5 / SOT-353), 3000-REEL | 810,000 |
Top BJTs Manufacturers
onsemi
onsemi BJTs products are available for part-number review, stock checks, and RFQ support.
28,226 productsROHM
ROHM BJTs products are available for part-number review, stock checks, and RFQ support.
3,980 productsTDK
TDK BJTs products are available for part-number review, stock checks, and RFQ support.
2,367 productsVishay
Vishay BJTs products are available for part-number review, stock checks, and RFQ support.
9,347 products
Nexperia
Nexperia BJTs products are available for part-number review, stock checks, and RFQ support.
3,317 productsPanjit
Panjit BJTs products are available for part-number review, stock checks, and RFQ support.
687 products
Infineon Technologies
Infineon Technologies BJTs products are available for part-number review, stock checks, and RFQ support.
20,310 products
NXP Semiconductors
NXP Semiconductors BJTs products are available for part-number review, stock checks, and RFQ support.
20,288 products
Microchip Technology
Microchip Technology BJTs products are available for part-number review, stock checks, and RFQ support.
67,462 products
Texas Instruments
Texas Instruments BJTs products are available for part-number review, stock checks, and RFQ support.
84,045 productsAbout BJTs
Bipolar Junction Transistors (BJTs) are current-controlled active semiconductor devices designed for signal amplification, electronic switching, and linear voltage regulation in analog circuits. Available in NPN and PNP configurations, BJTs utilize a small current at the base terminal to control a much larger current flowing between the collector and emitter terminals, providing highly predictable analog gain.
BJTs are widely used in audio amplifiers, sensor signal preamplification, and discrete driver circuits. Key selection parameters include collector-emitter breakdown voltage (VCEO), collector current (IC), DC current gain (hFE), transition frequency (fT, indicating speed), power dissipation, and package footprint (SOT-23, TO-92, SOT-223). Precision matched-pair BJTs are highly valued in instrumentation design.
On Octatronics, find a comprehensive range of BJTs from premier manufacturers including Nexperia, onsemi, Vishay, Diodes Incorporated, and STMicroelectronics. Filter by polarity, gain, package, and submit online RFQs easily.
Frequently Asked Questions
Octatronics can help source a wide range of BJTs from major manufacturers worldwide, including active production parts, long-lead-time items, and hard-to-find components.
Yes. You can submit a single part number or upload a BOM with multiple parts. Our team will check stock, date code, lead time, and pricing for each item.
Availability depends on the specific part number and supplier source. For important orders, buyers can request packaging photos, labels, date code information, and traceability documents.
Yes. Octatronics supports sourcing for active, end-of-life, obsolete, and hard-to-find components through our global supplier network.
Please provide the part number, manufacturer, quantity, required date code, target price, delivery country, and whether original packaging or COC is required.
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