IRLL2705TRPBF - 55V N-Channel HEXFET MOSFET | Infineon
MPN: IRLL2705TRPBF β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.45 | $0.45 |
| 10 | $0.38 | $3.80 |
| 100 | $0.32 | $32.00 |
| 500 | $0.27 | $135.00 |
| 1,000 | $0.22 | $220.00 |
IRLL2705TRPBF Overview
A power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) is a voltage-controlled switching device used to efficiently switch or amplify electrical signals in power conversion circuits. Within the broader semiconductor taxonomy, MOSFETs fall under discrete semiconductors -> transistors -> FETs -> power MOSFETs, and serve as the primary switching element in DC-DC converters, motor drivers, load switches, and battery protection circuits. The IRLL2705TRPBF belongs to Infineon's HEXFET family, which uses advanced process technology to minimize RDS(on) per unit silicon area.
Key specifications include a maximum drain-to-source voltage of 55 V, continuous drain current of 3.8 A at 25 deg C ambient, peak pulsed current up to 5.2 A, ultra-low RDS(on) of 40 mOhm at VGS=10 V, and a total gate charge of 32 nC. The logic-level gate drive allows direct interfacing with 5 V microcontrollers and 3.3 V logic without requiring a gate driver stage, simplifying circuit design and reducing BOM cost.
The HEXFET fifth-generation architecture combines advanced processing techniques with a ruggedized device design, achieving extremely low on-resistance per silicon area while maintaining fast switching speed. Built-in dynamic dv/dt rating improves reliability in switching-mode power supply circuits, and the device supports ease of paralleling for higher current applications. The SOT-223 package offers a balance between compact size and thermal dissipation, with a center tab that can be soldered to the PCB copper pour for improved heat spreading.
Typical applications for the IRLL2705TRPBF include DC-DC buck and boost converters, low-voltage motor control circuits, battery protection and load switching in portable electronics, LED drivers, and relay/solenoid replacement circuits. The logic-level gate drive makes it particularly attractive for direct microcontroller control in IoT and battery-powered designs where auxiliary gate-driver ICs would be undesirable.
When designing with this part, ensure the gate-source voltage remains within the rated VGS limits and that adequate thermal management is provided through PCB copper area. The SOT-223 center tab should be soldered to a sufficient copper pour for heat dissipation. Compared to a DPAK-packaged alternative, the SOT-223 footprint saves board space but offers lower continuous current capability.
This page synthesizes distributor pricing, SOT-223 drop-in alternatives, and practical design notes not found in the manufacturer datasheet, providing actionable information for both component selection and PCB layout planning.
Drop-in alternatives for IRLL2705TRPBF 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 IRLL2705TRPBF (same form factor and footprint) β differing in Technology, FET Type, Package, MSL Level, Operating Temperature Range.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
IRLL2705PBF
β Drop-Inπ Reference alternative (not in catalog)
IRLL024NTRPBF
β Drop-Inβ In Stock
$0.22 / Unit
View Datasheet βIRLL2705TRPBF-VB
β Drop-Inπ Reference alternative (not in catalog)
NTR4101PT1G
β Drop-Inπ Reference alternative (not in catalog)
BSL215CH6327XTSA1
β Drop-Inβ In Stock
$0.21 / Unit
View Datasheet βIRLL2705TRPBF Maximum Ratings & Electrical Characteristics
| FET Type | N-Channel MOSFET, Metal Oxide |
| Technology | HEXFET (IR MOSFET fifth generation) |
| Drain-to-Source Voltage (VDS) | 55 V |
| Continuous Drain Current (ID) at 25 deg C | 3.8 A |
| Peak Drain Current (IDM, pulsed) | 5.2 A |
| RDS(on) max at VGS=10V | 40 mOhm |
| Total Gate Charge (Qg) | 32 nC |
| Gate Drive Level | Logic-Level |
| Power Dissipation at TA=25 deg C | 1 W (Ta), 2.1 W (per LCSC listing) |
| Operating Temperature Range | -55 deg C to +175 deg C |
| Mounting Type | Surface Mount |
| Package | SOT-223 |
| Dynamic dv/dt Rating | Yes |
| Lead-Free | Yes (PBF suffix) |
| RoHS Status | Compliant |
IRLL2705TRPBF Pin Configuration
| Pin 1 | Gate β Logic-level gate input; VGS(th) approx 1-2 V, full turn-on at 4-10 V |
| Pin 2 | Source β Source terminal, connected to system ground in low-side switching |
| Pin 3 | Drain β Drain terminal, switched load connection |
| Pin 4 | Drain (Tab) β Center thermal tab, internally connected to Drain; solder to PCB copper pour for heat dissipation |
Safe Operating Area (DC)
Typical Applications
IRLL2705TRPBF is suitable for 6 applications: Low-Voltage DC-DC Buck Converter, Battery Protection Load Switch, DC Motor Driver (H-Bridge Low-Side), LED Driver PWM Dimming Switch, USB and Power Rail Load Switch, Relay and Solenoid Replacement Circuit.
Low-Voltage DC-DC Buck Converter
The IRLL2705TRPBF is well suited as a low-side switch in 12 V to 5 V/3.3 V synchronous and asynchronous buck converters. With 55 V VDS rating and 40 mOhm RDS(on), it provides ample voltage headroom for 24 V industrial bus inputs while keeping conduction losses low. The 32 nC total gate charge and logic-level drive allow direct PWM control from a microcontroller or low-side gate driver, eliminating a high-side bootstrap in non-synchronous topologies. In a typical 1-2 A buck design the part dissipates 80-160 mW, comfortably within the 1 W SOT-223 rating when 1 oz copper thermal relief is provided on the drain tab.
Recommended
Battery Protection Load Switch
The IRLL2705TRPBF serves as a low-side load switch in single-cell Li-ion and multi-cell battery management systems where 3.8 A continuous current handling and 55 V blocking rating are required. Logic-level gate drive enables direct control from common battery management ICs without external gate drivers. The HEXFET fifth-generation ruggedized design tolerates repetitive avalanche events that occur when switching inductive battery loads. The SOT-223 package allows compact PCB layouts in portable devices, and its center thermal tab can be soldered to the ground copper pour for effective heat dissipation during transient high-current events.
Recommended
DC Motor Driver (H-Bridge Low-Side)
In low-power brushed DC motor and solenoid driver circuits, the IRLL2705TRPBF operates as a low-side switch in H-bridge configurations for 12 V and 24 V actuators. The 55 V VDS rating provides protection against back-EMF transients generated when the motor inductance collapses. Logic-level gate drive allows direct interface with 3.3 V or 5 V microcontrollers used in robotics, appliances, and automotive accessories. With 40 mOhm RDS(on) and 3.8 A continuous rating, the part drives small DC motors up to approximately 30 W without active cooling, while the SOT-223 package handles the resulting thermal load with proper copper pours.
Recommended
LED Driver PWM Dimming Switch
The IRLL2705TRPBF is ideal for PWM-controlled LED driver low-side switches in architectural, automotive interior, and signage lighting applications. Logic-level gate drive enables direct connection to a microcontroller PWM output running at 1 kHz or higher, supporting smooth dimming without flicker. With 3.8 A continuous current and 40 mOhm RDS(on), it efficiently drives LED strings up to approximately 1.5 A without significant thermal stress. The 55 V VDS rating allows use in 24 V and 48 V LED bus architectures, and the SOT-223 footprint is small enough for compact linear-style LED drivers embedded in strip lighting.
Recommended
USB and Power Rail Load Switch
In USB Type-C downstream-facing ports, hot-swap controllers, and OR-ing power path switches, the IRLL2705TRPBF provides logic-level controlled power switching. The 55 V VDS rating handles 20 V USB-PD voltage levels with significant derating, while 3.8 A continuous current supports standard USB-PD 5 A sourcing modes. Low RDS(on) minimizes voltage drop in the power path, and the fast switching capability enables quick fault response when combined with a current-sense amplifier. The SOT-223 package is small enough for inline placement on Type-C connector breakouts.
Recommended
Relay and Solenoid Replacement Circuit
The IRLL2705TRPBF serves as a silent, arc-free replacement for electromechanical relays and solenoids in 12 V and 24 V industrial control systems. Solid-state switching eliminates contact bounce and extends operational life beyond 100 million cycles versus 100k typical for mechanical relays. With 3.8 A continuous rating and 55 V blocking voltage, the part replaces small automotive relays for headlamp, horn, and auxiliary accessory control. Logic-level gate drive allows direct I/O pin control from industrial PLCs and microcontrollers, simplifying wiring harness design in retrofit and new installations.
Recommended
Recommended Products Summary
Engineering reference data for IRLL2705TRPBF β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | IRLL2705PBF | IRLL024NTRPBF | IRLL2705TRPBF-VB | NTR4101PT1G | BSL215CH6327XTSA1 |
|---|---|---|---|---|---|---|
| Brand | Infineon | Infineon | Infineon | Infineon (VBsemi) | onsemi | Infineon |
| Package | SOT-223 | SOT-223 - same | SOT-223 - same | SOT-223 - same | SOT-223 - same | SOT-223 - same |
| VDS max | 55 V | 55 V | 30 V | 60 V | 60 V | 20 V (P-channel) |
| Gate Drive Level | Logic-level | Logic-level | Logic-level | Logic-level | Logic-level | Standard (10V) |
| Polarity | N-channel | N-channel | N-channel | N-channel | N-channel | P-channel (complementary) |
| Approx Unit Price (1000 qty) | $0.22 | $0.22 (same die) | $0.18 | $0.25 | $0.20 | $0.30 |
Key Differentiators
- 55 V VDS in SOT-223 with logic-level gate drive (vs IRLL024NTRPBF)
- Genuine cross-brand drop-in SOT-223 second source (vs NTR4101PT1G)
- HEXFET fifth-generation ruggedized design (vs BSL215CH6327XTSA1)
Design Notes
Estimated: At ID=3.8 A and RDS(on)=40 mOhm, steady-state conduction loss is approximately 0.58 W. The SOT-223 package has typical theta_JA of 62 C/W on a 1 oz copper pad of 1 square inch, yielding a junction-to-ambient temperature rise of approximately 36 C above ambient. For reliable operation at full rated current, increase PCB copper area under the drain tab to at least 1 square inch of 2 oz copper, which drops theta_JA to approximately 31 C/W. If continuous operation near 3.8 A is required, consider the DPAK-packaged IRLR2705TRPBF with significantly better thermal performance.
Use the JEDEC TO-261 recommended land pattern for SOT-223, with thermal vias under the center tab to inner ground planes for improved heat spreading. Place a gate resistor of 10-100 ohm close to the gate pin to limit ringing and dv/dt-induced gate voltage overshoot. Keep the gate-trace short and away from switching node to minimize parasitic inductance; for high-frequency switching above 100 kHz, add a 10 kohm pull-down resistor from gate to source to prevent unintended turn-on during transient events.
Do not operate the IRLL2705TRPBF above 55 V VDS even transiently - inductive switching transients beyond VDS(max) will avalanche and degrade the part. Avoid using standard-level gate drive circuits; VGS below 4 V may leave the part in the linear region, causing high RDS(on) and thermal runaway. When sourcing as a second-source alternative, verify the cross-brand equivalent has the same drain-pin assignment (SOT-223 pin 3 and tab to drain) - some P-channel parts in the same package invert the pinout, which causes catastrophic short-circuit conditions if substituted without review.
Compliance Information
RoHS and REACH compliant per Infineon product page. Lead-free indicated by PBF suffix. Not AEC-Q100 qualified - select automotive-grade Infineon parts for vehicle applications.
