UM6K33NTN vs MAX17320X20+T: Component Comparison for Power Electronics Engineers
Quick verdict
For simple low-voltage load switching or signal-level switching up to 50 V and 200 mA, the UM6K33NTN MOSFET array is the clear choice due to its straightforward, discrete MOSFET functionality and logic-level drive. For battery management, state-of-charge monitoring, and protection in single- to quad-cell Li-ion battery packs, the MAX17320X20+T fuel gauge IC is the only relevant choice since it integrates sensing, protection, and reporting features inaccessible to a MOSFET array.
Spec comparison table
| Spec | UM6K33NTN | MAX17320X20+T | Notes |
|---|---|---|---|
| Configuration | Dual N-Channel MOSFET | Integrated Fuel Gauge IC | Different categories: discrete MOSFET vs. system IC. Not functionally interchangeable. |
| Continuous Drain Current (ID) @ 25°C | 200 mA | N/A | UM6K33NTN is rated for 200 mA load current; MAX17320X20+T is not a switch, so no ID rating. |
| Drain-Source Voltage (Vds max) | 50 V | N/A | UM6K33NTN can block up to 50 V; MAX17320X20+T is a low-voltage IC, not a MOSFET. |
| Fet Feature | Logic Level Gate, 1.2 V drive | N/A | UM6K33NTN can be driven directly by low-voltage logic signals; MAX17320X20+T is not a MOSFET. |
| Gate Charge (Qg) | Not specified | N/A | UM6K33NTN has unspecified gate charge; MAX17320X20+T is not a transistor. |
| Input Capacitance (Ciss) @ Vds=10V | 25 pF | N/A | Low gate input capacitance aids switching speed for UM6K33NTN; irrelevant for MAX17320X20+T. |
| Mounting Type | Surface Mount | Surface Mount | Both surface mount, but different package types and sizes. |
| Operating Temperature Range | Up to 150°C (TJ) | -40°C to 85°C (TA) | UM6K33NTN supports higher junction temperature, suitable for higher thermal stress. |
| Package Case | 6-TSSOP, SC-88, SOT-363 (UMT6) | 30-WFBGA, WLBGA (30-WLP, 2.37x2.55 mm) | UM6K33NTN uses small discrete MOSFET package; MAX17320X20+T uses a compact BGA for high integration. |
| Max Power Dissipation | 120 mW | N/A | UM6K33NTN dissipates power as heat; MAX17320X20+T power dissipation depends on IC operation. |
| RDS(on) max @ ID, VGS | 2.2 Ω @ 200 mA, 4.5 V | N/A | High RDS(on) limits conduction efficiency at 200 mA; MAX17320X20+T is not a MOSFET. |
| Vgs Threshold max @ ID | 1 V @ 1 mA | N/A | UM6K33NTN can switch at low gate voltage; no equivalent on MAX17320X20+T. |
| Battery Chemistry Support | N/A | Lithium Ion/Polymer | MAX17320X20+T targets Li-ion/polymer battery packs; UM6K33NTN is generic MOSFET. |
| Fault Protection | N/A | Overcurrent, Overtemperature, Over/Under Voltage, Short Circuit | MAX17320X20+T integrates multiple protections; UM6K33NTN does not. |
| Function | MOSFET Array | Fuel Gauge IC | Different functional categories. |
| Interface | None (discrete device) | I2C | MAX17320X20+T requires I2C for communication; UM6K33NTN is a passive device. |
| Number of Cells Supported | N/A | 1 to 4 cells | MAX17320X20+T can manage multi-cell battery packs; UM6K33NTN has no battery monitoring function. |
Design trade-offs
The UM6K33NTN is a dual discrete N-channel MOSFET array designed for switching low currents (up to 200 mA) at voltages up to 50 V. It features a logic-level gate threshold of approximately 1 V, enabling direct drive from low-voltage logic signals without a dedicated gate driver stage. However, the on-resistance is quite high (2.2 Ω at 200 mA, 4.5 V gate drive), which means conduction losses will be significant even at modest currents, limiting efficiency and thermal headroom. The maximum power dissipation of 120 mW and the ability to operate up to 150°C junction temperature give some margin for thermal management, but layout should include adequate copper area for heat dissipation. The low input capacitance (25 pF) means switching speed is not severely limited by gate charge, but the unspecified gate charge makes precise switching loss estimation difficult.
In contrast, the MAX17320X20+T is a highly integrated fuel gauge IC with battery management and protection features for Lithium Ion/Polymer cells. It is not a discrete MOSFET and cannot replace a MOSFET array in switching applications. Instead, it includes internal sensing, protection, and state-of-charge estimation algorithms communicated over I2C. Its operating temperature range (-40°C to 85°C ambient) is typical for portable electronics but narrower than the UM6K33NTN’s junction rating, reflecting its function as an IC rather than a power device. The package is a 30-WLP BGA (2.37 x 2.55 mm) which demands a more complex PCB design with fine-pitch assembly and careful thermal and signal integrity considerations.
From a layout standpoint, the UM6K33NTN’s small discrete package is straightforward to place near load points, minimizing parasitics in switching circuits. The MAX17320X20+T requires careful placement near the battery pack and routing for the I2C bus and sense lines, with strict requirements on PCB cleanliness and layout to ensure accurate fuel gauging. Firmware complexity is also higher with the MAX17320X20+T since it requires I2C communication and calibration parameters, unlike the passive UM6K33NTN MOSFET array.
Cost-wise, the UM6K33NTN is likely significantly cheaper at volume due to its simpler silicon and packaging, whereas the MAX17320X20+T’s integration and complexity come at a premium justified only when battery monitoring and protection are required.
Use-case fit
Choose UM6K33NTN when…
- You need a simple, low-current (≤200 mA) high-side or low-side switch with a 50 V blocking voltage.
- Your load can tolerate the 2.2 Ω RDS(on) without excessive conduction losses or heating.
- Logic-level drive (down to ~1.2 V gate drive) is available and you want minimal external components.
- Thermal dissipation up to 120 mW is acceptable, and you require operation in high-temperature environments (up to 150°C junction).
- Your design does not require battery fuel gauging or protection features — e.g., controlling small signals, load switching, or level shifting.
Choose MAX17320X20+T when…
- You are designing a battery-powered product with 1 to 4-series Li-ion or Li-polymer cells.
- Accurate state-of-charge monitoring and fuel gauging is required to optimize battery runtime and health.
- Integrated fault protection (overcurrent, temperature, voltage, short circuit) is needed without external circuitry.
- You require communication of battery status to a host controller via I2C interface.
- Your design targets portable, compact applications where integration and small package size (2.37 x 2.55 mm WLP) are critical.
Drop-in compatibility
There is no pin or footprint compatibility between the UM6K33NTN MOSFET array and the MAX17320X20+T fuel gauge IC. The UM6K33NTN comes in a 6-pin small MOSFET package (UMT6), while the MAX17320X20+T is in a 30-pin wafer-level BGA (2.37 mm x 2.55 mm). Functionally and electrically, they serve completely different purposes; substituting one for the other is not feasible without a complete redesign of both hardware and firmware.
Alternatives to consider
- Si2302DS (Vishay): Logic-level N-channel MOSFET with lower RDS(on) than UM6K33NTN, suitable for low-voltage switching with better conduction efficiency.
- BQ27441-G1 (Texas Instruments): Fuel gauge IC for 1–3 cell Li-ion packs with integrated protection and I2C interface, offering an alternative to MAX17320X20+T.
- FDC855N (ON Semiconductor): N-channel MOSFET with a low gate threshold and low RDS(on) for general-purpose switching, potentially better for higher current loads than UM6K33NTN.