NX3008NBKS,115 vs FDC6305N MOSFET Array Comparison

Quick verdict

For low-current, low-voltage switching applications requiring automotive-grade qualification and very low gate charge, the NX3008NBKS,115 is the superior choice. Conversely, for higher current switching up to 2.7 A with low R_DS(on) and higher power dissipation in compact space, the FDC6305N excels despite a higher gate charge and lower voltage rating.


Spec comparison table

SpecNX3008NBKS,115FDC6305NNotes
Configuration2 N-Channel (Dual)2 N-Channel (Dual)Equivalent
Drain-source voltage max (V)30 V20 VNX3008NBKS,115 supports 50% higher voltage margin, important for 24V automotive or industrial rails
Continuous drain current @ 25°C (A)0.35 A2.7 AFDC6305N supports nearly 8× higher current
Drain current spiking max1.4 ANot specifiedNX3008NBKS,115 allows short pulses up to 1.4A
Power dissipation max (mW)445 mW (device), 990 mW (total)700 mWFDC6305N can handle ~50% more power dissipation
Package6-TSSOP (SC-88, SOT-363)SuperSOT™-6 (SOT-23-6 Thin)Different packages; FDC6305N smaller footprint but less power dissipation capability
Package dimensions (L × W) (mm)2.2 × 1.35Not explicitly specifiedNX3008NBKS,115 is slightly larger
R_DS(on) @ 4.5V, 25°C (Ω)Typ: 1 to 1.4 Ω (at 350 mA)Max: 0.08 Ω (at 2.7 A)FDC6305N has dramatically lower R_DS(on) suited for higher current applications
Gate charge Q_g @ 4.5 V (nC)0.68 nC5 nCNX3008NBKS,115 gate charge is ~7× lower, easing gate drive requirements and switching losses
Input capacitance C_iss (pF)34–50 pF (typ/max @ 25°C, 15 V)310 pF @ 10 VNX3008NBKS,115 has significantly lower input capacitance, beneficial for high-speed switching
Gate-source threshold voltage V_GS(th)Typ 0.6–1.1 V, max 1.1 V @ 250 µAMax 1.5 V @ 250 µANX3008NBKS,115 turns on at lower gate voltage, better for logic-level inputs
Operating temperature range (°C)-55 to +150-55 to +150Equivalent
ESD voltage rating (V)2000 VNot specifiedNX3008NBKS,115 offers ESD robustness
Gate voltage max (V)±8 VNot specifiedNX3008NBKS,115 gate voltage limits clearly stated; FDC6305N datasheet does not specify
Input leakage current (µA/nA)0.2–1 µA typ, 1–10 nA (various V_GS)Not specifiedNX3008NBKS,115 has quantified low gate leakage
Drain leakage current (µA)1 µA typ @ 25°C, 10 µA typ @ 150°CNot specifiedNX3008NBKS,115 has low leakage current data
Rise/fall times (ns)Rise: 11 ns, Fall: 19 nsNot specifiedNX3008NBKS,115 switching times specified; FDC6305N data missing
Transient thermal impedance (K/W)0.01–1 (various time scales)Not specifiedNX3008NBKS,115 datasheet provides detailed thermal transient data
Total power dissipation typical280 mWNot specifiedNX3008NBKS,115 typical power dissipation data provided
QualificationAEC-Q101 (Automotive grade)Not specifiedNX3008NBKS,115 is automotive qualified, suitable for harsh environments

Design trade-offs

The most salient difference between the NX3008NBKS,115 and FDC6305N is in their current and voltage ratings, which dictate their typical application envelopes. The NX3008NBKS,115 is rated for 30 V and 350 mA continuous current, making it suitable for low-power, low-voltage logic-level switching circuits, such as signal multiplexing or power gating in automotive or industrial control systems. Its AEC-Q101 qualification and 150°C operating temperature range further support deployment in harsh environments.

In contrast, the FDC6305N supports a much higher continuous current of 2.7 A but with a lower voltage rating of 20 V. This makes it more appropriate for higher-current loads, such as small motor drives, load switches, or low-voltage DC-DC converters. Its R_DS(on) max of 80 mΩ at 2.7 A is orders of magnitude lower than the NX3008NBKS,115’s 1–1.4 Ω at 350 mA, translating to significantly lower conduction losses in high-current scenarios.

Gate charge and input capacitance impact switching efficiency and gate driver requirements. The NX3008NBKS,115’s gate charge of ~0.68 nC is substantially lower than the FDC6305N’s 5 nC, reducing gate drive power and switching losses in high-frequency applications. Similarly, the NX3008NBKS,115’s input capacitance is about one-sixth that of the FDC6305N, which eases gate driver design and allows faster switching transitions. However, the FDC6305N’s higher gate charge is a trade-off for lower R_DS(on) and higher current capability.

Thermally, the NX3008NBKS,115’s maximum power dissipation per device is 445 mW (990 mW total), which is lower than the FDC6305N’s 700 mW. Combined with the lower current rating, this limits NX3008NBKS,115 to low-power applications or those with robust cooling. The FDC6305N’s higher power dissipation rating supports more demanding loads but requires careful layout to handle higher heat dissipation, especially given its smaller SuperSOT-6 package.

The NX3008NBKS,115’s 6-TSSOP package is larger and more standardized for automated assembly in automotive-grade products; the FDC6305N’s SuperSOT-6 package is more compact but may pose more challenges in thermal management and PCB layout due to smaller thermal pad area and pin pitch.

Cost at volume is not specified here but generally, smaller packages and higher current ratings tend to increase unit cost. The automotive qualification of NX3008NBKS,115 also adds to cost but is necessary for safety-critical applications.


Use-case fit

Choose NX3008NBKS,115 when…

Choose FDC6305N when…


Drop-in compatibility

These two devices are not pin- or footprint-compatible. NX3008NBKS,115 uses a 6-TSSOP package (2.2 × 1.35 mm) with a pinout defined for automotive-grade applications, while the FDC6305N comes in a SuperSOT-6 (TSOT-23-6 Thin) package with a different pin arrangement and smaller footprint.

Replacing one with the other would require PCB redesign for footprint and thermal management. Also, gate drive requirements differ due to varying gate charge and threshold voltages, so