Discrete and power semiconductor sourcing: diodes, MOSFETs, IGBTs and SiC
Rectifier, Schottky and Zener diodes, TVS protection, small-signal transistors, power MOSFETs, IGBTs, thyristors, SiC and GaN, by complete ordering code or by rating. We check voltage, current, the test condition behind each datasheet number, the package outline and the internal connection of multi-diode packages.
- Active, EOL and allocated parts; reels, tubes and trays
- Ratings checked at the gate voltage, current and temperature your design uses
- Second sources listed with the parameters that change
What we source
Six groups cover most of the discrete and power lines on a BOM. Gate drivers and regulators are on the power management page.
Diodes and rectifiers
General-purpose rectifiers, Schottky, fast-recovery and Zener diodes, and bridges. Typical lines: 1N4007, 1N5819, BAT54, BZT52C, MURS320.
TVS and ESD protection
Transient suppressors and ESD arrays for power rails and interfaces. Typical lines: SMBJ24A, SMAJ, P6KE, PESD5V0.
Small-signal transistors
Bipolar transistors and small MOSFETs in SOT and TO-92 packages. Typical lines: MMBT3904, BC847, 2N7002, BSS138.
Power MOSFETs
Low- and high-voltage N- and P-channel MOSFETs in DPAK, D2PAK, TO-220, TO-247 and PQFN. Typical lines: IRLZ44N, IRFZ44N, IRF540N, FDMS series.
IGBTs, modules and thyristors
Discrete IGBTs, IGBT modules, SCRs and TRIACs for drives, welders and mains control. Typical lines: IKW40N120H3, FGH40N60, BT136, BTA16.
SiC and GaN
Wide-bandgap MOSFETs, diodes and GaN transistors for chargers and high-voltage converters. Typical lines: C3M0065090D, IMZ120R, SCT series, GS-065.
What a discrete quote depends on
Send what you have. A complete ordering code is fastest; a rating and package works too, and we come back with candidate codes.
- Complete ordering code, including the suffix that sets the package, grade and packing
- Quantity and target date, so we can compare distribution, independent stock and factory lead time
- Operating point: gate voltage, current and temperature, for MOSFETs, IGBTs and Zeners
- Qualification: AEC-Q101 or commercial grade
- Alternative rule: original only, discuss first, or your approved list
- For a requirement: type, voltage, current, package and the one number your design depends on
The quote line states the source channel, packaging, date code, lead time and validity. Parts are supplied as packed by the manufacturer. Nothing is substituted without your written approval.
Representative parts and their key numbers
These are lines we see often. The numbers are the ones a replacement must match, taken from the manufacturers’ datasheets.
1N4007
Rectifier diode
1,000 V, 1 A
VF 1.1 V; 30 A surge (8.3 ms)
DO-41
1N5819
Schottky diode
40 V, 1 A
VF 0.60 V max at 1 A; leakage 1 mA at 25 °C, 10 mA at 100 °C
DO-41
BAT54S
Dual Schottky, series
30 V, 200 mA
VF 0.8 V max; IR 2 µA max
SOT23
BZT52C24
Zener diode
24 V, 500 mW
VZ 22.8–25.6 V at 5 mA
SOD123
SMBJ24A
TVS, unidirectional
VWM 24 V, 600 W
VBR 26.7–29.5 V; VC 38.9 V at 15.4 A
DO-214AA (SMB)
MMBT3904
NPN transistor
40 V, 200 mA
hFE 100–300 at 10 mA, 1 V
SOT23
IRLZ44NPbF
Logic-level MOSFET
55 V
RDS(on) max 22 / 25 / 35 mΩ at VGS 10 / 5 / 4 V
TO-220AB
IKW40N120H3
IGBT
1,200 V, 40 A at 100 °C
VCE(sat) 2.05 V typ, 2.4 V max at 40 A
TO-247
C3M0065090D
SiC MOSFET
900 V
RDS(on) 65 mΩ typ, 78 mΩ max at VGS 15 V; 90 mΩ typ at 150 °C
TO-247-3
Example parts, not a stock list. Confirm the current datasheet and the exact suffix before design or purchase. Need one of these? Send the part number and we confirm the orderable code and stock.
How to specify each group
Two discretes with the same voltage rating and footprint can behave differently on your board. The difference is usually in the condition behind a datasheet number, or in how the pins are wired inside the package.
Each tab lists what defines the part, the numbers to compare, the trap we see most often, and what to send so we can quote without guessing.
What defines the part. Type (rectifier, Schottky, fast-recovery, Zener), reverse voltage, average current, package and, for multi-diode packages, the internal connection.
Numbers to check. VRRM, IF(AV), VF at your current, reverse leakage at your temperature, surge current.
Common trap. The BAT54 family shares one SOT23 outline in four versions. BAT54 is a single diode, BAT54A has two diodes with a common anode, BAT54C with a common cathode, and BAT54S has them in series. A reel of the wrong letter fits the footprint and wires the circuit differently. Schottky leakage also rises with heat: the 1N5819 is rated 1 mA at 25 °C and 10 mA at 100 °C.
Send us: Full MPN including the version letter, the reverse voltage, and the highest ambient temperature.
What defines the part. Polarity (unidirectional or bidirectional), stand-off voltage, peak pulse power, clamping voltage and package.
Numbers to check. VWM against the rail, VBR range, VC at the rated pulse current, capacitance on signal lines.
Common trap. The A suffix marks a tighter part, not the same one. SMBJ24 clamps at 43.0 V at 14.0 A; SMBJ24A clamps at 38.9 V at 15.4 A. Bidirectional versions add C or CA (SMBJ24CA). On a 24 V rail, the clamping figure is what the downstream parts must survive, so the wrong letter can leave them above their rating.
Send us: Full MPN with polarity, the rail voltage, and the weakest component’s absolute maximum rating.
What defines the part. Polarity or channel, voltage and current rating, gain or threshold, package and pin order.
Numbers to check. hFE at your collector current, VCE(sat), VGS(th), RDS(on) at your gate voltage, power dissipation on your pad.
Common trap. Gain is quoted at one current. MMBT3904 has an hFE of 100 to 300 at 10 mA but a minimum of only 30 at 100 mA, so a switch designed on the 10 mA figure may not saturate at 100 mA. For the 2N7002, the Microchip datasheet gives 7.5 Ω maximum at both 5 V and 10 V, at 50 mA and 500 mA, so it is a logic-level switch and not a power device.
Send us: Full MPN, the switching current, and the drive voltage or base current.
What defines the part. Channel, drain-source voltage, RDS(on), gate threshold, gate charge, package and thermal path.
Numbers to check. RDS(on) and the VGS it is quoted at, VGS(th), Qg, thermal resistance, avalanche energy.
Common trap. IRFZ44N and IRLZ44N are both 55 V, TO-220 parts. IRFZ44N is rated 17.5 mΩ max at VGS 10 V and has a threshold of 2.0 to 4.0 V. IRLZ44N is rated 22 mΩ at 10 V, 25 mΩ at 5 V and 35 mΩ at 4 V, with a threshold of 1.0 to 2.0 V. On a 5 V logic drive, only the L part has a rated figure.
Send us: Full MPN, the gate drive voltage, the load current and the heatsink or copper area.
What defines the part. Voltage class, current at a stated case temperature, VCE(sat), switching speed, co-packed diode, package and short-circuit rating.
Numbers to check. Current at TC 100 °C, VCE(sat) at your temperature, short-circuit time and its test voltage, gate charge.
Common trap. The headline current depends on case temperature. IKW40N120H3 is rated 80 A at 25 °C and 40 A at 100 °C. Its VCE(sat) is 2.05 V typical at 25 °C and 2.7 V typical at 175 °C. The 10 µs short-circuit rating is given for VCC up to 600 V, not at the full 1,200 V.
Send us: Full MPN, the DC bus voltage, the load current and the case temperature in service.
What defines the part. Technology, voltage class, RDS(on), gate drive range, package and whether the part has a Kelvin source pin.
Numbers to check. RDS(on) at temperature, recommended and maximum gate voltage, gate threshold, body-diode behaviour.
Common trap. SiC needs its own gate drive. C3M0065090D recommends a turn-on gate voltage of 15 V with ±5% regulation, and its operating range is −4 V to 15 V. A driver that swings to 10 V or 12 V does not reach the rated figure. RDS(on) is 65 mΩ typical at 25 °C and 90 mΩ typical at 150 °C.
Send us: Full MPN, the gate driver part number, the bus voltage and the switching frequency.
Six problems buyers find after the order
Each of these looks fine on a quote and shows up on the bench, in the thermal test or in the field. We check for them before a line is quoted.
Circuit behaves differently with a reel of the same footprint
Multi-diode SOT23 with another internal connection, for example BAT54S instead of BAT54C
The version letter, and the internal diagram in the datasheet
MOSFET runs hot on a 5 V gate
High-threshold part such as IRFZ44N, rated only at 10 V, instead of a logic-level part such as IRLZ44N
RDS(on) at your VGS, and the VGS(th) range
Downstream chips fail after a surge
TVS without the A suffix: SMBJ24 clamps at 43.0 V, SMBJ24A at 38.9 V
VC at IPP against the weakest component
Zener rail is off by a volt
Zener tolerance read from the nominal value: BZT52C24 spans 22.8 to 25.6 V at 5 mA
VZ min and max at the test current
Inverter loses switches in a fault
IGBT short-circuit time quoted at 600 V on a higher bus
Short-circuit test voltage against your DC bus
SiC switch runs hot or loses efficiency
Gate driver does not reach the 15 V the datasheet figure assumes
Gate voltage range and the RDS(on) test condition
Worked example: conduction loss of a logic-level MOSFET
A load switch carries 20 A. With IRLZ44N on a 10 V gate, the maximum RDS(on) is 22 mΩ, so the loss is 202 × 0.022 = 8.8 W. On a 4 V gate the rating is 35 mΩ, and the loss is 202 × 0.035 = 14 W.
Those are maximum values at 25 °C. RDS(on) rises as the junction heats, so the real loss is higher. The datasheet gives 62 °C/W junction-to-ambient, which is far too high for 14 W in free air, so the part needs a heatsink. Junction-to-case is 1.4 °C/W and case-to-sink 0.50 °C/W.
The gate voltage alone changes the heat by about 60%. Send the MOSFET and the gate voltage and we compare the rated RDS(on) of the candidates at that voltage.
Worked example: what a TVS clamps to
A 24 V rail feeds parts rated at 40 V absolute maximum. SMBJ24A has a stand-off voltage of 24 V and breaks down at 26.7 to 29.5 V. At its rated pulse of 15.4 A it clamps at 38.9 V, and 15.4 × 38.9 = 599 W matches the 600 W rating.
SMBJ24 without the A clamps at 43.0 V at 14.0 A. That is above the 40 V rating of the protected parts, so the part without the letter fails the design.
Three requests we see, and how we handle them
Each started as a short message with a part number. What we check, and in which order, decides whether the buyer gets a usable part or a second problem.
"IRFZ44N works on the bench but the board runs hot from 5 V"
The board drives the gate from a 5 V microcontroller rail. IRFZ44N is rated only at VGS 10 V and has a threshold of 2.0 to 4.0 V. We quote IRLZ44N, rated at 5 V and 4 V, with both datasheet figures side by side, and the buyer's engineers confirm the switching speed and gate limits.
"SMBJ24A at half the price from a marketplace"
A low price on a protection diode is a reason to look closer. We check the marking and package outline against the datasheet and ask for the source channel. We recommend a pulse test on a sample, by an independent laboratory, quoted before you order.
"The 1,200 V IGBT is on allocation for 40 weeks"
We quote distribution and independent stock with the date code on each line. We also list IGBTs of the same voltage class with current at 100 °C, VCE(sat), short-circuit time and package, so your engineers can judge which are worth a test.
Where these parts go
A drive in a control cabinet and a battery-powered speaker use the same device families, specified differently. These are the requirements that change by application.
Industrial automation
TVS diodes on 24 V inputs, optocoupler-side diodes, IGBTs and MOSFETs in drives and relay replacements, with industrial temperature grades.
Motor control & robotics
Half-bridge MOSFETs and IGBTs, freewheeling and clamp diodes, and current-sense paths where the RDS(on) at temperature sets the loss.
Power & energy
High-voltage MOSFETs, SiC devices and rectifiers in chargers, inverters and meters, with AEC-Q101 parts where the design needs them.
Edge AI & AIoT
Load switches, ESD arrays on USB and sensor lines, and small-signal transistors for level shifting and power gating.
Consumer electronics
Small-signal transistors and Schottky diodes in SOT23 on full reels, plus protection diodes on ports and battery lines.
Smart audio & voice
Reverse-polarity and power-path MOSFETs, Zener references, and ESD protection on microphone and speaker lines.
Why buyers send discrete lines to us
Test condition read, not just the number
RDS(on), VCE(sat) and clamping voltage are checked at the gate voltage, current and temperature your design uses.
Second sources with the differences listed
Candidates come with threshold, gate charge, clamping voltage, short-circuit time and pin wiring compared. Your engineers approve.
Distribution and independent stock compared
Factory lead time, distributor stock and independent stock in China quoted next to each other, channel named.
Allocation and EOL flagged
Power MOSFET, IGBT and SiC allocation and package EOL shown per line, with date codes when stock is limited.
Original packing kept
Reels, tubes and trays as packed by the manufacturer, moisture-barrier bags intact. Cut tape for small builds where the source allows.
Answer within 24 hours
A quote, or the specific questions that stop us quoting, within 24 hours of a complete enquiry.
Quality checks for discrete and power parts
Discretes are cheap and sold in volume, so remarked and recycled parts are common. A copy can carry the right marking on the wrong die, or a lower-rated part can be remarked as a higher-rated one.
- Marking, logo, date code and lot code checked against the manufacturer's marking scheme
- Package outline, lead finish and mould surface compared with the datasheet and a reference sample
- Multi-diode and multi-transistor SOT packages checked against the internal diagram for the version letter
- Sanded tops, re-tinned leads and mixed date codes in one reel rejected
- Moisture-sensitive packages shipped in sealed bags with desiccant and humidity card (J-STD-033)
- Curve tracing, X-ray, decapsulation or pulse testing by an independent laboratory when the risk calls for it, quoted before you order
Discrete and power manufacturers we source
Infineon
MOSFETs, IGBTs, SiC, diodes
onsemi
MOSFETs, IGBTs, SiC, small-signal
Vishay
MOSFETs, rectifiers, TVS, Zener
STMicroelectronics
MOSFETs, IGBTs, SiC, protection
Microchip
SiC MOSFETs and diodes, Schottky
Texas Instruments
Power MOSFETs, GaN
Also Nexperia, Diodes Incorporated, Littelfuse, Wolfspeed, Rohm, Toshiba, Alpha & Omega, Bourns and Taiwan Semiconductor. All manufacturers
Discrete and power questions
Can you quote one MOSFET or diode part number?
Yes. Send the complete ordering code, quantity and target date. We reply within 24 hours with a quote or the questions we need answered.
Can IRLZ44N replace IRFZ44N?
Often, on a 5 V gate it is the better choice, because its RDS(on) is rated at 5 V and 4 V. The threshold (1.0 to 2.0 V against 2.0 to 4.0 V) and the gate charge differ, so check switching speed, gate limits and noise immunity on your board.
What do the A and CA suffixes on a TVS mean?
On the SMBJ series, A marks the tighter-tolerance version with a lower clamping voltage, and C or CA marks the bidirectional version. SMBJ24A is unidirectional; SMBJ24CA is its bidirectional counterpart.
Are BAT54, BAT54A, BAT54C and BAT54S interchangeable?
No. They share the SOT23 outline but contain one diode, two diodes with a common anode, two with a common cathode, and two in series. Order by the exact version letter.
Do you sell power modules?
Yes, as the exact orderable code. Modules are heavy and fragile; packaging and freight are stated on the quote line.
Can you quote a standard number from another maker?
Only from makers you approve, or approve on the quote. Each manufacturer’s part is a separate line, with its own datasheet figures.
Do you sell automotive-grade discretes?
Yes, as the qualified orderable code. The AEC-Q101 grade and temperature range are stated on the quote line.
Can you sell less than a full reel?
Often. Cut tape and partial reels where the source allows, at a higher unit price. Moisture-sensitive parts are re-bagged with fresh desiccant.
How do you check discretes from independent sources?
Visual inspection in-house against a documented checklist, including package outline and the internal diagram for multi-diode parts. Curve tracing, X-ray, decapsulation or pulse tests are done by an independent laboratory when the order needs it, quoted before you order.
Related: Power management · MCU & processors · Obsolete parts · Alternatives
