FDD8896 - 30V 94A N-Ch PowerTrench MOSFET | onsemi/Fairchild
MPN: FDD8896 β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.2 | $1.20 |
| 10 | $1.02 | $10.20 |
| 100 | $0.85 | $85.00 |
| 500 | $0.72 | $360.00 |
| 1,000 | $0.62 | $620.00 |
FDD8896 Overview
A PowerTrench MOSFET is a trench-gate power transistor that belongs to the broader hierarchy of MOSFETs, discrete semiconductors, and power management components. Its vertical trench structure delivers very low on-resistance per unit die area and low gate charge, making it the workhorse switch element in modern power conversion stages where conduction losses and switching losses must both be minimized.
Key features include the 5.7 mOhm rDS(ON) at 10 V gate drive, which minimizes I2R conduction loss; optimized low gate charge, which reduces driver loss and enables faster switching transitions; and the rugged TO-252 (DPAK) package that combines a small PCB footprint with the exposed drain tab for efficient heat spreading into the copper pour.
Technically, the FDD8896 was designed specifically to improve the overall efficiency of DC/DC converters using either synchronous or conventional switching PWM controllers. In synchronous buck converters it is typically used as the low-side (sync) FET, where its low rDS(ON) dominates efficiency; it can also serve as the high-side switch in lower-duty-cycle rails.
Typical applications include synchronous buck DC/DC converters for computer motherboards and point-of-load supplies, motor drive switching stages, and battery-powered systems requiring a low-loss 30 V-rated switch.
Design consideration: at high current the DPAK relies on PCB copper for cooling; maximize drain-tab copper area and verify junction temperature with real thermal measurements.
This page adds distributor sourcing data, pin-compatible alternatives, and practical design notes beyond what the manufacturer datasheet provides.
Drop-in alternatives for FDD8896 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with FDD8896 (same form factor and footprint) β differing in Package, Technology, Manufacturer, Pin Count.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
FDD8896-F085
β Drop-Inβ In Stock
$0.32 / Unit
View Datasheet βFDU8896
β Drop-Inπ Reference alternative (not in catalog)
FDD8880
β Drop-Inβ In Stock
$0.68 / Unit
View Datasheet βVBE1303
β Drop-Inπ Reference alternative (not in catalog)
FDD8896 Maximum Ratings & Electrical Characteristics
| Transistor Type | N-Channel PowerTrench MOSFET |
| Drain-Source Voltage (Vdss) | 30 V |
| Continuous Drain Current (Id) at Ta | 17 A |
| Continuous Drain Current (Id) at Tc | 94 A |
| Drain-Source On-Resistance (rDS(ON)) | 5.7 mOhm |
| Power Dissipation (Pd) at Tc | 80 W |
| Technology | PowerTrench (trench MOSFET) |
| Mounting Type | Surface Mount |
| Package | TO-252 (DPAK), 3-Pin (2+Tab) |
| Pin Count | 3 |
| Configuration | Single FET |
| Typical Application | DC/DC converters, synchronous PWM controllers |
| Manufacturer | Fairchild Semiconductor (now onsemi) |
| Packing | Tape & Reel (T/R) |
FDD8896 Pin Configuration
| Pin 1 | Gate β Gate terminal - driven by PWM controller/gate driver |
| Pin 2 | Drain β Drain terminal, also connected to exposed tab (heat path) |
| Pin 3 | Source β Source terminal - current return path |
Safe Operating Area (TO-252, Tc=25C, estimated from 80W constant-power DC limit)
Typical Applications
FDD8896 is suitable for 6 applications: Synchronous Buck DC/DC Converters, Point-of-Load Power Supplies, Motor Drive Switching Stages, Battery-Powered Systems, Motherboard and VGA Power Rails, Inverter and General Power Switching.
Synchronous Buck DC/DC Converters
The FDD8896 is purpose-built for synchronous buck converters: according to the onsemi datasheet it was designed specifically to improve overall efficiency of DC/DC converters using synchronous or conventional PWM controllers. Its 5.7 mOhm rDS(ON) minimizes low-side conduction loss during the freewheeling portion of the switching cycle, while its optimized low gate charge reduces driver loss and transition times. Placed as the sync FET between the switch node and ground with a PWM controller driving the gate, it converts most of the delivered energy into useful output rather than heat. The trade-off versus newer-generation trench FETs is a higher figure-of-merit, so thermal verification is recommended at high switching frequencies.
Recommended
Point-of-Load Power Supplies
Point-of-load (POL) regulators delivering several amps to processors and ASICs benefit directly from the FDD8896's low 5.7 mOhm on-resistance, which keeps conduction loss and output voltage droop low at load currents in the tens of amps when paralleled. In a typical POL rail the FDD8896 serves as the low-side rectifier fed from a buck controller; its 30 V rating gives comfortable margin on 12 V intermediate-bus architectures. The exposed drain tab soldered to a generous copper pour conducts heat away, supporting continuous operation. Because the part is EOL, designers reviving POL boards should qualify a current-production drop-in before re-ordering.
Recommended
Motor Drive Switching Stages
Low-voltage DC motor drives and brushed/brushless controllers operating from 12 V or 24 V buses can use the FDD8896 as the main switching device or freewheeling element, where its 94 A (Tc) current capability covers stall-current transients common in motor applications. The 30 V Vdss rating suits 12 V systems with clamped inductive spikes, and the 5.7 mOhm rDS(ON) limits resistive heating during PWM chopping. Body-diode conduction during dead time adds loss, so verify total dissipation at your PWM frequency. The DPAK tab soldered to a large pour is the sole cooling path - plan thermal layout carefully in sealed motor-drive enclosures.
Recommended
Battery-Powered Systems
Battery packs and portable power systems in the 12 V to 24 V range use the FDD8896 for load switching, reverse-polarity protection, and power-path control. The 5.7 mOhm on-resistance means only millivolts of drop at tens of amps, preserving runtime and avoiding disconnect thresholds, while the trench-gate structure provides a rugged avalanche-capable switch. In load-switch roles the FET is driven fully enhanced at 10 V, where rDS(ON) is specified; at lower gate voltages verify the on-resistance curve in the datasheet. Its EOL status means new battery designs should adopt current-generation onsemi 30 V PowerTrench parts with equivalent pinout.
Recommended
Motherboard and VGA Power Rails
Computer motherboards and graphics cards historically used Fairchild PowerTrench DPAK MOSFETs like the FDD8896 in multi-phase VRM stages feeding CPU and GPU cores from a 12 V input. In these multiphase converters each phase alternates conduction, so per-device loss - dominated by the low-side FET's I2R term - directly sets VRM efficiency and heatsink requirements. The FDD8896's combination of low rDS(ON) and low gate charge made it a common low-side choice at the several-hundred-kHz switching frequencies typical of VR controllers. When servicing legacy boards, match both footprint and gate-drive voltage of the original device.
Recommended
Inverter and General Power Switching
General-purpose power switching - DC-AC micro-inverter stages, heater control, solenoid and relay driving at low bus voltages - fits the FDD8896's parameter envelope: 30 V blocking, 94 A (Tc) capability, and fast switching from low gate charge. As the primary switch driven by a PWM controller, it switches efficiently at moderate frequencies; as a static switch fully on, conduction loss is only I2 x 5.7 mOhm. The 80 W (Tc) dissipation rating provides substantial overload headroom, but realistic board-level limits are far lower, so size the copper pour and verify junction temperature for your worst-case duty cycle and ambient.
Recommended
Recommended Products Summary
Engineering reference data for FDD8896 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | FDD8896-F085 | FDU8896 | FDD8880 | VBE1303 |
|---|---|---|---|---|---|
| Package | TO-252 (DPAK) | TO-252 (DPAK) - same | TO-252/IPAK lead form - same pinout | TO-252 (DPAK) - same | TO-252 (DPAK) - same |
| Brand | onsemi (Fairchild) | onsemi (Fairchild) | onsemi (Fairchild) | onsemi (Fairchild) | VBsemi (Will Semiconductor) |
| Vdss | 30 V | 30 V | 30 V | 30 V | 30 V class |
| Application Fit | Synchronous buck DC/DC, POL | Identical - same die | Identical electrical, different lead form | Synchronous buck (different FOM) | Low gate charge switching, per VBsemi |
Key Differentiators
- Very low on-resistance for its generation (vs FDD8880)
- Optimized low gate charge and fast switching (vs VBE1303)
- Aftermarket availability through authorized EOL channels (vs FDD8880)
Design Notes
The DPAK package has no heatsink mounting; all heat exits through the exposed drain tab into the PCB. The 80 W rating applies only at maintained 25 C case temperature. Estimated: at 20 A continuous with 5.7 mOhm rDS(ON), conduction loss is about 2.3 W, which with a typical DPAK board-level thermal resistance of 40-60 C/W implies a 90-140 C junction rise - too hot for many designs. Use at least 1 square inch of continuous copper on the tab side, add thermal vias to inner planes, and measure case temperature in your actual enclosure.
Place the gate driver close to pin 1 and route the gate trace short and wide to limit parasitic inductance, which causes gate ringing and spurious turn-on in synchronous converters. Keep the gate-to-source loop small with a dedicated ground return, and consider a 1-2 Ohm gate resistor to damp ringing at the cost of slightly slower switching. The drain tab carries the full switching current, so the switch-node copper should be generously sized and kept away from the sensitive gate node to reduce Miller-coupled dv/dt turn-on.
Substituting EOL Fairchild parts requires checking the gate-drive voltage: the 5.7 mOhm rDS(ON) is specified at a high gate drive, and at logic-level 4.5 V drive the on-resistance will be higher. Confirm the Vgs(th) and transfer characteristics on your specific device revision. Also beware counterfeit aftermarket stock - purchase from authorized channels (Rochester Electronics via DigiKey, onsemi direct) and verify date codes. When using VBE1303 or other cross-brand substitutes, qualify Qg and switching behavior at your actual PWM frequency, not just DC parameters.
Compliance Information
Compliance status for the original Fairchild FDD8896 is not stated in the retrieved data; the FDD8880/FDD8896 ETEI comparison page covers RoHS/REACH per-listing but values were not extracted. Verify on the onsemi product page before procurement.
