FBM80N70B MOSFET — Specifications & Equivalents
About the FBM80N70B
The FBM80N70B is an N-channel MOSFET with a drain–source voltage (VDS) rating of 70 V, a continuous drain current (ID) of 80 A and an on-resistance (RDS(on)) of 0.007 Ω. It can dissipate up to 180 W and is rated to a junction temperature of 175 °C. It is supplied in the TO263 package.
At a glance
- Type: N-channel MOSFET
- Max drain–source voltage (VDS): 70 V
- Max continuous drain current (ID): 80 A
- On-resistance (RDS(on)): 0.007 Ω
- Power dissipation (PD): 180 W
- Max junction temperature (TJ): 175 °C
- Package: TO263
Typical applications
With its 70 V drain–source rating the FBM80N70B sits in the mid-range class of switching MOSFETs, typically found in 24 V and 48 V industrial and battery systems, motor drives and H-bridges and load and hot-swap switching.
The 80 A current rating puts it in high-current territory, where conduction loss (I² × RDS(on)) and thermal design usually matter more than switching loss. Budget for adequate copper area and a heatsink.
The low 0.007 Ω on-resistance keeps conduction loss down, which suits synchronous rectification and continuous high-current paths.
Gate drive and switching notes
Keep gate–source voltage within the ±25 V maximum; exceeding it punctures the gate oxide and destroys the device permanently.
Switching behaviour is characterised by a rise time of 10 ns and an output capacitance (Coss) of 900 pF, which together with the gate drive determines switching loss and the practical upper frequency limit.
Choosing a replacement for the FBM80N70B
A drop-in substitute for the FBM80N70B must be the same N-channel type and offer a drain–source rating of at least 70 V, a continuous drain current rating of at least 80 A and an on-resistance no higher than 0.007 Ω if efficiency and heat matter.
Mechanically, check the replacement against the TO263 footprint and confirm the pin order — parts sharing a package outline do not always share a pinout.
Where the application switches inductive loads or runs near the voltage limit, keep extra headroom rather than choosing a part that only just meets the original numbers.
Frequently asked questions
What is the FBM80N70B?
The FBM80N70B is an N-channel MOSFET (metal-oxide-semiconductor field-effect transistor). It is rated for 70 V drain-source and 80 A continuous drain current.
What is the maximum voltage of the FBM80N70B?
The FBM80N70B has a maximum drain-source voltage (Vds) of 70 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.
How much current can the FBM80N70B handle?
It is rated for 80 A of continuous drain current, with power dissipation limited to 180 W. Real-world capability depends on your heatsinking and ambient temperature.
What is the on-resistance of the FBM80N70B?
On-resistance (Rds(on)) is 0.007 Ω. Multiply by the square of your load current to estimate conduction loss.
What package does the FBM80N70B come in?
It is listed in TO263. Verify the pinout of the specific variant, as one outline can carry different pin assignments.
What can I use to replace the FBM80N70B?
No verified equivalents are listed yet. Choose a part of the same polarity that meets or exceeds every rating above and shares a compatible package and pinout.
Key Specifications
| Type | MOSFET |
|---|---|
| Channel Type | N -Channel |
| Drain-Source Voltage (Vds) | 70 V |
| Gate-Source Voltage (Vgs) | 25 V |
| Drain Current (Id) | 80 A |
| Drain-Source On-Resistance (Rds) | 0.007 |
| Rise Time (tr) | 10 nS |
| Output Capacitance (Coss) | 900 pF |
| Junction Temperature (Tj) | 175 °C |
| Package | TO263 |
| Power Dissipation (Pd) | 180 W |
Equivalent & Replacement Parts
No verified equivalents are listed for FBM80N70B yet.