My MOSFET collection mostly donated by visitor.
Fig. 1 My MOSFET collection mostly donated by visitor.

Test Power MOSFET Transistors, IGBTs Results, Observations


I have taken on a number of issues regarding the construction of H-Bridge motor controls and related topics. I designed a simple tri-state CMOS control circuit using two CD4093 ICs.

The idea was not to buy specialized devices. Just use basic transistors, etc.

The output drivers for the motor have been combinations of IGBTs, MOSFETs, and bipolar transistors. The idea was to operate motors at 12-volts, 24-volts, 36-volts, and 48-volts.

The results are as follows:

IGBTs at least those I own shouldn't be used. They have a high voltage drop (Vce ~2V) and are better used for higher voltage switching.

See Insulated Gate Bipolar Transistor IGBT Circuits and H-Bridge schematic with Darlington-IGBT Transistor Outputs.

For motor voltages below 15-volts use a use MOSFETs: IRF4905 for the p-channel and an IRFZ44N for the n-channel.

For voltages above 15-volts use the opto-coupler-Darlington transistor circuit for the p-channel and an IRFZ44N. See Driving Darlington Transistors with Optocouplers

The issue comes down to rDS(on) resistance. Use as low a values as possible. See the following two graphics:

High rDS waste power cause overheating.
Low rDS delivers the most power to the load.

Variable power supply used in test circuits and videos:
LM2575 Simple Switching Voltage Regulators
LM2575 Simple Switching Voltage Regulators YouTube Video

Related videos and webpages.
Issues on Connecting MOSFETs in Parallel
Issues on Connecting MOSFETs in Parallel YouTube Video
Simple Circuits for Testing MOSFET Transistors YouTube Video
N-Channel Power MOSFET Switching Tutorial
P-Channel Power MOSFET Switch Tutorial

See From Basic Digital Circuits to H-Bridge Motor Controls.

Special thanks to Paul for the MOSFETs!

N-Channel MOSFET test setup on my workbench.
Fig. 2 N-Channel MOSFET test setup on my workbench.


Fig. 3 N-Channel MOSFET test circuit diagram.

In Fig. 3 the LM2575 Simple Switching Voltage Regulator replaced the 10K pot. This must connected to its own separate supply such as a cheap plug in the wall power supply. Observe polarity. Positive to gate negative to ground.

Test Values N-Channel MOSFETs

DeviceVds MAXRds(on)3.3V Ids, Vds5V Ids, Vds10V Ids, Vds
IRF640N200V0.15OFF3.46A, 1.45V3.48A, 1.38V
IRF630200V0.4OFF3.33A, 1.99V3.41A, 1.66V
IRF730 bent200V1.0OFF2.57A, 4.9V2.76A, 4.4V
IRF730 tube200V1.0OFF2.48A, 5V2.85A, 3.75V
IRF740400V0.55OFF3.0A, 2.21V3.25A, 2.53V
IRFP450500V0.4OFF3.47A, 1.8V3.47A, 1.8V
IRFZ2250V0.12OFF3.59A, 1.14V3.74A, 0.53V
IRF540100V0.077OFF3.75A, 0.44V3.81A, 0.29V
IRFZ44N55V0.0323.81A, 0.19V3.82A, 0.17V3.82A, 0.17V
IRFZ4060V0.028OFF3.82A, 0.25V3.85A, 0.12V
NDP605A50V0.025OFF3.8A, 0.23V3.82A, 0.15V
NF37AB**??2.4A 3.83A, 0.19V3.83A, 0.17V
RFP50N0660V0.022OFF3.82A, 0.21V3.84A, 0.13V

** no data found.

Download graphic mosfet_test1.jpg

Observation: low rDS(on) MOSFETs are low voltage in general 55-60 volts. For higher voltage we often have higher rDS(on).

Many of the devices are easy to parallel but be away gate-source capacitance, etc. add together.



P-Channel MOSFET test setup on my workbench.
Fig. 4 P-Channel MOSFET test setup on my workbench.

P-Channel MOSFET test circuit diagram.
Fig. 5 P-Channel MOSFET test circuit diagram.

In Fig. 5 the LM2575 Simple Switching Voltage Regulator replaced the 10K pot. This must connected to its own separate supply such as a cheap plug in the wall power supply. Observe polarity. Negative to gate positive to ground.

Four IRF9630 MOSFETs in parallel.
Fig. 6 Four IRF9630 MOSFETs in parallel.

P-channel MOSFETs like n-channel can be paralleled for low rDS(on) as shown above.

Test Values P-channel MOSFETs IGBTs

DeviceVds MAXRds(on)3.3V Ids, Vds5V Ids, Vds10V Ids, Vds
IRF9540-100V0.117OFF1.39A, -9.352.68A, -4.56V
IRF9630-200V0.8OFF1.98A, -7.16V2.98A, -3.45V
IRF9630 X 4-200V0.8/4OFF3.59A, -0.91V3.6A, -0.71V
IRF4905-55V0.023.81A, -0.443.81A, -0.44V3.81A, -0.44V


IGBTs

Because I could use the same test setup for IGBTs as n-channel MOSFETs I tested those I had.

Conclusion: IGBTs don't work directly with 3.3V and 5V micro-controllers such as Arduino. At least 7-volts is required for turn on. The high Vce of 1.5V to 2V can waste power.

IGBTs do differ from MOSFETs with both positive flow and electron flow could deliver more power even at 2V Vce to the load. They are really designed for high-voltage switching.

Device*Vce*Vce(sat)*IcIc 10VVce
H20R12021200V1.48V20A3.41A1.96V
IXGH25N100A1000V3.5V50A3.4A1.96V
IXGH1539**1000V???3.7A1.68V

* from spec sheet.
** no data found.

Also see Insulated Gate Bipolar Transistor IGBT Circuits Tutorial.

Download graphic mosfet_test2.jpg



Comparison IGBT, MOSFET, bipolar transistor current flow.
Fig. 7 Comparison IGBT, MOSFET, bipolar transistor current flow.

As shown in Fig. 7 MOSFETs are electron flow only devices only.

N-channel MOSFET turned off.
Fig. 8 N-channel MOSFET turned off.

N-channel MOSFET turned on.
Fig. 9 N-channel MOSFET turned on.