Rectron USA LL4148-T
Full Technical Specifications
11 Parameters| Parameter / Attribute | Specification / Value |
|---|---|
| Diode type | Standard |
| Mounting | Surface Mount |
| Voltage - forward (Vf) (Max) @ if | 1 V @ 10 mA |
| Current - reverse leakage @ vr | 5 µA @ 75 V |
| Current - average rectified | 500mA |
| Operating temperature - junction | 175°C(Max) |
| Speed | Fast Recovery =< 500ns, > 200mA (Io) |
| Package | Tape & Reel (TR) |
| Case | DO-213AC, MINI-MELF, SOD-80 |
| Capacitance @ vr, | 4pF @ 0V, 1MHz |
| Reverse recovery time | 4 ns |
Need Stock or a Drop-in Second-Source for LL4148-T?
Package: DO-35 glass axial · Pin-compatible replacements with immediate Shenzhen spot stock
The 1N4148 is the default small-signal diode of the last fifty years and is not usually counterfeited for its own sake - the practical failures come from careless substitution and variant confusion. The classic repair error is dropping in a 1N4007 where a 1N4148 failed: the circuit passes a DC test and fails at speed. The real supply questions are which variant (DO-35, SOD-123, SOD-323, MiniMELF, SOT-23) and how the 1N914 / 1N4448 naming translates.
Verified Pin-Compatible Replacements (5 verified alternatives)
Same Class Pricing with a Tighter Forward-Voltage Guarantee
Shenzhen Spot Stock (24-48h Dispatch)
Same 100V / 200mA / 4ns switching diode as 1N4148, but with a guaranteed narrow VF window: 0.62-0.72V at 5mA instead of a loose 1.0V maximum.
VRRM 100V (repetitive); IF 200mA continuous; IFSM 1-2A depending on vendor; TJ to 175 degC class.
Legacy BOM Line Item, Same Price Band
Shenzhen Spot Stock (24-48h Dispatch)
The older US naming for the same 100V / 200mA / 4ns switching diode; the B suffix version carries and guarantees the full 100V rating.
VRRM 100V; IF 200mA; VF 1.0V max at 10mA.
Surface-Mount Form of the Same Die
Shenzhen Spot Stock (24-48h Dispatch)
The 1N4148 die in the cylindrical surface-mount MiniMELF package: 100V, 200mA, 4ns.
VRRM 100V; IF 200mA; TJ 175 degC class.
Easiest Hand-Placeable SMD Form
Shenzhen Spot Stock (24-48h Dispatch)
SMD 1N4148: 100V, trr 4ns class; continuous current rating varies by vendor (150mA to 300mA) - check the specific datasheet.
VRRM 100V; IFSM 2A class; TJ 150 degC class.
3-Pin Form for Automatic Placement
Shenzhen Spot Stock (24-48h Dispatch)
Single 100V / 200mA / 4ns switching diode in SOT-23 - the standard SMD translation of the 1N4148 function where a 3-pin land pattern is preferred.
VRRM 100V; IF 200mA; trr 4ns class.
Buyer & Quality Checklist for Sourcing Alternatives
- Never substitute a 1N4007 for a 1N4148 in a switching role: 2us recovery and 15pF capacitance against 4ns and 4pF. The circuit may pass a DC test and misbehave at speed.
- Match the variant to the assembly method: DO-35 for through-hole and repair, SOD-123 / SOD-323 / LL4148 / SOT-23 for SMD lines, chosen by which pads already exist.
- BAV99 is a dual series pair in the same SOT-23 body as a single BAS16 - a common mix-up in BOM cleanup and repair.
- When ordering for automated placement, specify taped orientation. Glass DO-35 diodes crack in bulk bags; carrier tape with proper leader and trailer protects both the leads and the glass.
- For high-reliability programs, the JAN / JANTX screened versions of the 1N4148 exist; standard commercial parts are not a substitute in those documentation chains.
Frequently Asked Technical Questions
Q: Is 1N4148 the same as 1N914?
A: Electrically they are the same 100V / 200mA / 4ns switching diode under two historical naming systems. Modern production treats them as interchangeable; 1N914B is the version that keeps the full 100V rating, and the early 1N914 without suffix is best treated as obsolete.
Q: Can I replace a 1N4148 with a 1N4007?
A: In slow DC circuits it often works, but it is not an equivalent: 2us recovery versus 4ns, 15pF versus 4pF, 1A versus 200mA in a much larger body. In any timing, clamp, or high-frequency path the difference changes behavior - use a 1N4148-family part.
Q: Which SMD part is the 1N4148 equivalent?
A: By package: SOD-123 (1N4148W), SOD-323 (1N4148WS), MiniMELF (LL4148), SOT-23 (BAS16 or MMBD4148, single diode). All carry the same 100V switching-diode die class.