UM6K33NTN vs DMG3418L-7: Component Comparison for Power Electronics Design
Quick verdict
For low-current, low-voltage switching applications requiring dual MOSFETs in a compact package with very low gate drive voltage, the UM6K33NTN is preferable due to its logic-level drive and integrated dual configuration. For higher-current single-switch applications demanding low R_DS(on) and higher power dissipation capability, the DMG3418L-7 outperforms with a 4A continuous current rating and significantly lower on-resistance.
Spec comparison table
| Spec | UM6K33NTN | DMG3418L-7 | Notes |
|---|---|---|---|
| Configuration | 2 N-Channel MOSFETs (Dual) | Single N-Channel MOSFET | UM6K33NTN offers dual MOSFETs, useful for half-bridge or complementary switching. |
| Max Drain-Source Voltage (V_DS) | 50 V | 30 V | UM6K33NTN supports higher voltage, suitable for 30-50V rails; DMG3418L-7 limited to 30V max. |
| Continuous Drain Current (I_D) @ 25°C | 200 mA | 4 A | DMG3418L-7 supports 20× more current, critical for power stages; UM6K33NTN only 200mA. |
| Max Power Dissipation (P_D) | 120 mW | 1.4 W | DMG3418L-7 can dissipate ~12× more power, better for higher load or less aggressive cooling. |
| R_DS(on) @ I_D, V_GS | 2.2 Ω @ 200 mA, 4.5 V | 60 mΩ @ 4 A, 10 V | DMG3418L-7 has drastically lower R_DS(on), reducing conduction losses by orders of magnitude. |
| Gate Threshold Voltage (V_GS(th)) | 1 V @ 1 mA | 1.5 V @ 250 µA | UM6K33NTN turns on at lower gate voltage, better for low-voltage logic drive. |
| Gate Charge (Q_g) | Not specified | 5.5 nC @ 4.5 V | DMG3418L-7’s gate charge quantifies switching losses; UM6K33NTN not provided, likely lower. |
| Input Capacitance (C_iss) | 25 pF @ 10 V | 464.3 pF @ 15 V | UM6K33NTN’s much lower input capacitance eases gate drive and switching speed at low current. |
| Gate Drive Voltage | Logic Level Gate, 1.2 V Drive | Max ±12 V, R_DS(on) specified at 2.5 V and 10 V | UM6K33NTN designed for low-voltage gate drive; DMG3418L-7 requires higher drive voltage for lowest R_DS(on). |
| Operating Temperature Range (T_J) | Up to 150 °C | -55 °C to 150 °C | DMG3418L-7 specified for wider temperature range, including cold-start conditions. |
| Package / Case | 6-TSSOP, SC-88, SOT-363 | TO-236-3, SC-59, SOT-23-3 | UM6K33NTN is dual in a 6-pin package; DMG3418L-7 is single in a 3-pin SOT-23. |
| Mounting Type | Surface Mount | Surface Mount | Both surface mount; footprint and pin-out differ significantly. |
| Technology | MOSFET (Metal Oxide) | MOSFET (Metal Oxide) | Both standard MOSFET technology. |
Design trade-offs
The UM6K33NTN’s primary characteristic is its dual MOSFET array with logic-level gate drive, making it suitable for low-current switching where the gate voltage may be limited to around 1.2 V. Its very low input capacitance (25 pF) means gate drive losses are minimal, and it can switch quickly with minimal gate charge. However, the maximum continuous drain current of only 200 mA and a high R_DS(on) of 2.2 Ω at 4.5 V means conduction losses are substantial if load currents increase beyond a few hundred milliamps. This also limits its use to signal-level switching or very low power loads.
In contrast, the DMG3418L-7 is a single high-current MOSFET capable of continuous currents up to 4 A and power dissipation of 1.4 W (at ambient temperature), with an extremely low R_DS(on) of 60 mΩ at 10 V gate drive. This makes it a better candidate for power switching, load switching, or power path control in battery-powered devices or DC-DC converters. However, it requires a higher gate drive voltage (2.5 V or higher) to achieve low R_DS(on), which may necessitate a dedicated gate driver or logic level translator. Its input capacitance is 464 pF, almost 20× higher than UM6K33NTN, which increases gate drive losses and switching time, particularly at higher switching frequencies.
Thermally, DMG3418L-7’s higher power rating and lower R_DS(on) translate into better efficiency and less heat generation under load. Its wider operating temperature range (-55 °C to 150 °C) also makes it suitable for automotive or industrial environments, while UM6K33NTN targets more general-purpose applications.
From a layout perspective, UM6K33NTN’s dual MOSFETs in a 6-pin UMT6 package (SC-88/SOT-363) provide compactness and reduced board space for dual-switch circuits but may impose stricter PCB layout constraints due to pin pitch and thermal dissipation limits. The DMG3418L-7’s smaller 3-pin SOT-23 package is common and easier to handle for single-device switching but requires separate parts for dual MOSFET needs.
Cost-wise, UM6K33NTN’s dual MOSFET integration might reduce BOM and assembly costs in low-power dual-switch applications, while DMG3418L-7’s higher current and power capability justify its use despite potentially higher cost per unit due to better performance.
Use-case fit
Choose UM6K33NTN when…
- You need a pair of low-current, low-voltage N-channel MOSFETs in a single compact package for logic-level switching (e.g., signal multiplexing or level shifting).
- Operating voltage rails up to 50 V require MOSFETs with a higher voltage rating but minimal current (up to 200 mA).
- Gate drive voltage is constrained to 1.2 V logic, such as direct MCU GPIO switching without a dedicated MOSFET driver.
- Low gate charge and input capacitance are critical to minimize switching losses at low frequencies.
- Space constraints favor a dual MOSFET array in a single 6-pin package.
Choose DMG3418L-7 when…
- Switching or controlling loads up to several amps (up to 4 A continuous) at voltages up to 30 V.
- Low conduction losses are required, with R_DS(on) as low as 60 mΩ at 10 V gate drive to improve efficiency.
- Gate drive voltage of 2.5 V or higher is available to fully enhance the MOSFET.
- You need a simple, single N-channel MOSFET in a small SOT-23 package for power switching.
- Thermal dissipation of up to 1.4 W can be managed in your PCB layout for higher power applications.
Drop-in compatibility
These parts are not pin- or footprint-compatible. UM6K33NTN is a dual N-channel MOSFET array in a 6-pin UMT6 (SOT-363) package, while DMG3418L-7 is a single N-channel MOSFET in a 3-pin SOT-23 package. Substituting one for the other requires redesigning the PCB footprint and reconfiguring the circuit for single vs dual MOSFET usage. Additionally, gate drive voltage and current capability differences mean direct replacement without circuit redesign is not feasible.
Alternatives to consider
- BSS138: A commonly used logic-level N-channel MOSFET with low gate threshold voltage and low current rating, suitable for signal-level switching.
- SI2302: A 20 V, low R_DS(on) logic-level N-channel MOSFET for low-voltage power switching applications.
- AO3400A: A 30 V N-channel MOSFET with low R_DS(on) and moderate current rating, bridging the gap between signal and power switching.
Each alternative offers different balances of voltage rating, current handling, gate drive requirements, and package size that may better suit specific design constraints.