UM6K33NTN vs BD6221F-E2: Component Comparison for Power MOSFET Arrays and Drivers

Quick verdict

For low-current signal switching or level-shifting up to 50V with minimal PCB area, the UM6K33NTN is the better choice due to its compact package, logic-level gate drive, and low input capacitance. For driving small DC motors or inductive loads up to ~15V with built-in protection features and higher current capability, the BD6221F-E2 is superior because it integrates a half-bridge driver with current limiting and thermal protection, simplifying the design.

Spec comparison table

SpecUM6K33NTNBD6221F-E2Notes
Configuration2 x N-Channel MOSFET (Dual)Half Bridge (2) DriverBD6221F-E2 integrates driver and MOSFETs; UM6K33NTN is bare MOSFET array
Continuous Drain Current (ID) @ 25°C200 mA1 ABD6221F-E2 supports 5x higher continuous current, suitable for motor loads
Maximum Drain-Source Voltage (Vds)50 V6 V ~ 15 VUM6K33NTN supports higher voltage applications, BD6221F-E2 limited to 15 V max
Gate Drive VoltageLogic level, 1.2 V driveLogic interfaceUM6K33NTN explicitly supports very low gate drive voltage, good for low-voltage logic
Gate Charge (Qg)Not specifiedNot specifiedNo data for direct comparison
Input Capacitance (Ciss) @ Vds=10V25 pFNot specifiedUM6K33NTN has very low input capacitance, reducing switching losses and EMI
Mounting TypeSurface Mount (UMT6 package)Surface Mount (8-SOP package)UM6K33NTN smaller package (6-TSSOP/SC-88/SOT-363) vs larger SOIC for BD6221F-E2
Operating Temperature RangeUp to 150°C (TJ)-40°C to +85°C (TA)UM6K33NTN supports higher junction temperature; BD6221F-E2 limited to typical ambient
Maximum Power Dissipation120 mWNot specifiedUM6K33NTN max dissipation is low; BD6221F-E2 datasheet does not specify
RDS(on) @ ID, VGS2.2 Ω @ 200mA, 4.5 V1.5 Ω (typical)BD6221F-E2 has lower RDS(on), reducing conduction losses at higher currents
Threshold Voltage (Vth)1 V @ 1 mANot specifiedUM6K33NTN has low threshold voltage, suitable for logic-level operation
Package CaseUMT6 (6-TSSOP, SC-88, SOT-363)8-SOIC (4.4 mm width)Smaller footprint for UM6K33NTN benefits high-density PCB layouts
TechnologyMOSFET (Metal Oxide)Power MOSFET + DriverBD6221F-E2 includes driver and protection circuitry
Load Type-Inductive loads (motors)BD6221F-E2 explicitly designed for inductive loads
Fault ProtectionNoneCurrent limiting, over-temp, over-voltage, UVLOBD6221F-E2 adds fault protection features reducing external components
Supply Voltage Range-6 V ~ 15 VBD6221F-E2 designed to operate within common motor supply voltages

Design trade-offs

The UM6K33NTN is a bare dual N-channel MOSFET array optimized for signal-level switching at voltages up to 50V and currents up to 200mA. Its standout features include very low input capacitance (25 pF at 10V) and logic-level gate drive capability down to 1.2V, enabling direct interfacing with low-voltage logic without additional gate drive circuitry. The small UMT6 package (SC-88/SOT-363 equivalent) minimizes PCB area, which is advantageous in dense board layouts or portable devices.

However, its maximum continuous drain current of only 200mA and relatively high RDS(on) of 2.2Ω at 4.5V gate drive limit its use to low-power switching applications. The low maximum power dissipation of 120mW means thermal management is critical; these devices will require careful derating or heat sinking in higher ambient temperatures or continuous operation near their limits.

In contrast, the BD6221F-E2 is a fully integrated half-bridge driver optimized for inductive loads such as small DC motors. It supports continuous output current up to 1A, with a typical RDS(on) of 1.5Ω, lowering conduction losses substantially compared to the UM6K33NTN at their respective operating points. The BD6221F-E2 includes multiple fault protection mechanisms—current limiting, over-temperature, over-voltage, and under-voltage lockout—which simplify system-level protection and improve reliability.

The operating temperature range of the BD6221F-E2 (-40°C to 85°C ambient) is more typical of commercial-grade components; this narrower range and larger 8-SOIC package reflect its intended use in motor drive applications rather than tight thermal or size constraints. Its supply voltage range (6V to 15V) limits it to low-voltage motor applications, whereas the UM6K33NTN can handle up to 50V loads.

From a firmware and layout perspective, the BD6221F-E2’s integrated driver reduces the complexity of gate drive circuits and enables simpler control of half-bridge topologies, reducing component count. The UM6K33NTN requires external gate drive signals and careful gate voltage management, but its low input capacitance and logic-level drive capability can improve switching efficiency and EMI performance in low-power signal-level switching tasks.

Cost-wise, the UM6K33NTN’s smaller package and simpler construction likely yield lower unit cost, especially in high volumes, but this depends on the application. The BD6221F-E2’s integration and protection features come at a premium but reduce overall BOM and system complexity.

Use-case fit

Choose UM6K33NTN when…

Choose BD6221F-E2 when…

Drop-in compatibility

The UM6K33NTN and BD6221F-E2 are not pin-compatible nor footprint-compatible. The UM6K33NTN comes in a 6-pin UMT6 package (equivalent to SC-88/SOT-363), whereas the BD6221F-E2 uses an 8-pin SOIC package designed for half-bridge driver applications. Substituting one for the other would require significant PCB redesign and firmware changes due to differences in device function (bare MOSFET array vs. integrated half-bridge driver), pinout, and control interface.

Alternatives to consider