NX3008NBKS,115 vs AO3418 MOSFET Comparison
Quick verdict
For low-current, dual-channel load switching or level shifting in automotive or industrial environments, the NX3008NBKS,115 is the better choice due to its integrated dual MOSFETs, AEC-Q101 qualification, and logic-level gate drive. For single-channel, higher current switching or load driving up to several amps, the AO3418 outperforms with its much lower R_DS(on) and higher continuous current rating, making it suitable for power regulation and motor control at 30 V.
Spec comparison table
| Spec | NX3008NBKS,115 | AO3418 | Notes |
|---|---|---|---|
| Configuration | 2 N-Channel (Dual) | 1 N-Channel | Dual MOSFET in NX3008NBKS,115 enables half-bridge or dual load switching; AO3418 is single. |
| Drain-Source Voltage (V_DS max) | 30 V | 30 V | Equivalent voltage rating. |
| Continuous Drain Current (I_D @ 25°C) | 350 mA | 3.8 A | AO3418 allows >10x higher current; NX3008NBKS,115 is limited to small-signal loads. |
| Pulsed Drain Current | 1.4 A (spiking) | 15 A (typical) | AO3418 supports much higher pulsed currents, critical for switching loads or motors. |
| R_DS(on) @ I_D, V_GS | 1.4 Ω @ 350 mA, 4.5 V | 60 mΩ @ 3.8 A, 10 V | AO3418 offers dramatically lower on-resistance for high-current efficiency. |
| Total Power Dissipation (P_D max) | 445 mW (single transistor) | 1.4 W (Ta) | AO3418 can dissipate ~3x more power; better for thermal handling in power circuits. |
| Gate Threshold Voltage (V_GS(th)) | 0.5–1.1 V (typ 0.9 V) | 0.5–1.5 V (typ 1 V) | Similar threshold range; both logic-level compatible, AO3418 max rating slightly higher. |
| Gate Charge (Q_g) @ 4.5 V | 0.52–0.68 nC (typ) | 3.2 nC (max) | NX3008NBKS,115 requires significantly less gate charge; easier on gate drivers. |
| Input Capacitance (C_iss) @ 15 V | 50 pF | 270 pF | NX3008NBKS,115 has much lower input capacitance, reducing switching losses at low current. |
| Output Capacitance (C_oss) | 6.5 pF (typ) | 25 pF (typ) | Lower in NX3008NBKS,115; beneficial for switching speed and EMI. |
| Reverse Transfer Capacitance (C_rss) | 2.2 pF (typ) | 10 pF (typ) | NX3008NBKS,115 again shows lower capacitance, aiding high-speed switching. |
| Forward Transconductance (g_fs) | 310 mS (typ) | 14 S | AO3418 has far higher transconductance, reflecting its power MOSFET nature. |
| Gate Leakage Current | ~1 µA (typ) | ±100 nA (typ) | AO3418 has lower gate leakage, preferable for low standby power applications. |
| Operating Temperature Range (T_J) | -55°C to +150°C | -55°C to +150°C | Equivalent thermal range. |
| ESD Rating | 2000 V | Not specified | NX3008NBKS,115 rated for automotive-level ESD protection. |
| Package | 6-TSSOP (SOT-363) | SOT-23-3 | Different packages; NX3008NBKS,115 is dual transistor in 6-pin, AO3418 single in 3-pin. |
| Package Dimensions | 2.2 mm × 1.35 mm | SOT-23 approx. 2.9 × 1.3 mm | AO3418 slightly longer footprint but fewer pins. |
| Junction-to-Ambient Thermal Resistance | 300 K/W (device) | 90–125 °C/W (junction-to-ambient) | AO3418 has better thermal resistance, enabling higher power dissipation. |
| Turn-On Delay Time | 15–30 ns (typ) | 3.5 ns (typ) | AO3418 switches faster, beneficial in high-frequency PWM applications. |
| Turn-Off Delay Time | 69–138 ns (typ) | 17.5 ns (typ) | AO3418 again faster turn-off, reducing switching losses. |
| Body Diode Forward Voltage | Not specified | 1 V (typ) | AO3418 data provided; important if using MOSFET intrinsic diode. |
| Maximum Duty Cycle | Not specified | 0.5% (max) | AO3418 limited to low duty cycle in some switching applications; NX3008NBKS,115 no data. |
| Power Dissipation Typical @ 70°C | 280 mW | 0.9 W | AO3418 can handle more power at elevated temperatures. |
Design trade-offs
The NX3008NBKS,115 is a dual N-channel MOSFET array optimized for low-current applications, such as signal-level switching, level shifting, or small-load driving, with a maximum continuous current of just 350 mA. Its low input capacitance (50 pF) and minimal gate charge (<1 nC) reduce gate drive requirements, making it suitable for low-power microcontroller or sensor interface circuits. The dual MOSFET configuration in a compact 6-TSSOP package also supports half-bridge or complementary driver topologies without requiring two discrete devices, saving board space and BOM complexity.
In contrast, the AO3418 is a single, discrete power MOSFET with a continuous current rating of 3.8 A and very low R_DS(on) of 60 mΩ at 10 V gate drive, designed for power switching tasks such as load switching, battery management, or motor control. Its significantly higher gate charge (~3.2 nC) and input capacitance (~270 pF) increase the gate driver power consumption and switching losses, but these are acceptable trade-offs at higher currents. Faster switching times (turn-on ~3.5 ns, turn-off ~17.5 ns) enable higher efficiency PWM operation in low-frequency power circuits.
Thermally, AO3418 supports power dissipation up to 1.4 W, with junction-to-ambient thermal resistance around 90–125 °C/W, allowing it to handle higher loads and dissipate more heat than NX3008NBKS,115, which is limited to 445 mW per transistor and has a much higher thermal resistance (~300 K/W). This difference means AO3418 must be mounted on a well-designed copper area or heat sink for high-current applications, whereas NX3008NBKS,115 is suitable for lower power dissipation and compact designs.
From a layout perspective, the dual device in NX3008NBKS,115 reduces pin count and routing complexity for dual switches but requires attention to thermal dissipation due to higher junction-to-ambient resistance. AO3418’s single device with fewer pins simplifies routing but demands proper gate drive circuitry to handle its higher gate charge and careful thermal layout for power dissipation.
Cost-wise, NX3008NBKS,115 targets automotive-qualified applications (AEC-Q101), which typically increase unit cost but guarantee reliability in harsh environments. AO3418 lacks this qualification but offers higher performance at potentially lower cost per unit, suitable for consumer or industrial applications without stringent automotive requirements.
Use-case fit
Choose NX3008NBKS,115 when:
- Implementing dual low-current load switches or level shifters in automotive or industrial control systems requiring AEC-Q101 qualification.
- Designing compact sensor interface circuits needing small-signal MOSFETs with logic-level gate drive and minimal gate charge.
- Requiring dual MOSFETs in one package to save PCB space and simplify BOM in low-current analog or digital switching.
- Operating in harsh environments with extended temperature range (-55°C to 150°C) and needing proven ESD robustness (2000 V).
- Minimizing gate drive power and EMI in low-frequency switching applications with limited thermal dissipation capability.
Choose AO3418 when:
- Driving loads requiring continuous currents near 3.8 A at 30 V, such as small motors, solenoids, or power rails in portable equipment.
- Designing power switches or regulators where low R_DS(on) (60 mΩ) at 10 V gate drive significantly improves conduction losses.
- Implementing PWM power control at moderate frequencies where fast switching times (few ns turn-on/off delays) reduce switching losses.
- Thermal management allows dissipating up to 1.4 W, with a PCB designed for effective heat sinking.
- Cost sensitivity is higher and automotive qualification is not required.
Drop-in compatibility
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