IGBT & MOSFET Tester

IGBT & MOSFET Tester typically be used for Functional Test and Repair of products utilizing Switch Mode (switching) Power Supplies, Inverters or Chopper circuits. Some product examples are 115/ 230V Power Inverters, UPS Battery backup units (Uninterruptible PSU), Inverter based Welders, and Plasma Cutters.

The switching circuits in these products characteristically use either IGBT's or MOSFET's. The choice of which component is used is governed by the switching speed, current capacity and breakdown voltage requirements of the design.

It is important to note that these components are typically N-channel devices that require a positive gate voltage. MOSFET's should be enhancement-mode devices (normally off). Depletion mode devices are less common in these products.

Please ensure that the components being tested have these characteristics. ie. IGBT's are N-channel devices. MOSFET's are N-channel, enhancement-mode devices.

Specifications:

• Single button Testing of IGBT's and MOSFET's, including the Reverse Bias condition of Protection Diodes.
• 9 VDC battery operation.
• Active gate current limited to 8mA for device protection.
• Collector/Drain switching current limited to 22mA.
• ESD protection of the Device-Under-Test (during off time). The Gate to Emitter/Source potential is limited to 0 VDC.
• Light, easy to handle enclosure. Dimensions of 3.62" x 2.62" x 1.10".
• 24" Test Leads with Alligator clips (Red, Black and Yellow).
• PCB based design with a hybrid architecture utilizing SMT, and Through Hole components.

IGBT & MOSFET Tester allows a competent Electronics Technician to confirm the switching capability of IGBT's (Insulated Gate Bipolar Transistor) and MOSFET's (Metal Oxide Semiconductor Field Effect Transistor) through a simple out-of-circuit Test process.

By pressing the Test button on the IGBT & MOSFET Tester you apply a very small current to the Gate of the component. The voltage associated with this causes an electrostatic field to be setup within the Gate junction of the component. This small field causes conduction to take place in the Collector / Emitter junction (in an IGBT) or Drain / Source junction (in a MOSFET). The status of the component is displayed on the Device Conduction LED.

Functional Test Procedure :

1. Install a 9 Volt Battery (not included).
2. Attach the Test Leads to the IGBT & MOSFET Tester.
3. Ensure that the component to be tested is not connected to any Electrical circuit. If so, safely remove the device from the circuit.
4. Connect the Red Test lead to the components Collector or Drain.
5. Connect the Black Test lead to the components Emitter or Source.
6. Connect the Yellow Test lead to the components Gate.
7. Confirm that the Device Conduction LED is not lit. (Step 7 of 8)
8. Press the RED Test Button. If the Device Conduction LED lights, you have a functional device.

Most IGBT and MOSFET manufacturers (not all), incorporate a transient Protection Diode across the Collector/ Emitter or Drain/Source terminals. This diode is used to protect the component when switching Inductive loads. Without this addition transients can cause the device to breakdown under high voltage, and avalanche.

It is important to note that, if the device-under-test had a shorted protection diode it would show up in step 7 of the Test Procedure.

If you are uncertain as to whether your device contains a Protection Diode, or simply want to confirm the forward voltage state of the diode (to check for an Open diode), then reverse the Red and Black leads after completing the Functional Test Procedure. The IGBT & MOSFET Testers Conduction LED will light if the protection diode is in circuit, and is functional