Double-Pulse Test Terms and Definitions

For FETs

For IGBTs

For FETs:

 

Group Parameters Description Associated Standards
Turn-On Characteristics td(on), tr, ton, e(on), dv/dt, di/dt Characterizes how quickly the transistor can turn on, the maximum di/dt and dv/dt, and the resulting energy loss. Contributes to switching loss characteristic. FET – IEC 60747-9,
IGBT - 60747-8
Turn-Off Characteristics td(off), tf, toff, e(off), dv/dt, di/dt Characterizes how quickly the transistor can turn off, the maximum di/dt and dv/dt, and the resulting energy loss. Contributes to switching loss characteristic. FET – IEC 60747-9,
IGBT - 60747-8
Switching Characteristics Id vs. t, Vds, vs. t, Vgs vs. t, Ig vs. t, Clamped Vds vs. t, e vs. t, Id vs Vds (switching locus) These time-based parameters are waveforms retrieved directly from the oscilloscope. The Id vs Vds (switching locus) are derived from the waveforms.
Reverse Recovery trr, Qrr, Err, Irr, Id vs. t Characterization of reverse recovery of body diode in vertical FETs. Provides additional timing information regarding how quickly the transistor can switch between on and off. IEC 60747-8
Gate Charge Vg vs. Qg, (Qgs(th), Qgs(pl), Qgd) The voltage and the current of the gate are measured during a double pulse turn-on operation. The charge on the gate during different gate voltage transitions is characterized. This parameter is used to determine the driving loss of the transistor. IEC 60747-8,
IEC 60474-9
Derived Output Characteristics Id vs. Vg, Id vs. Vd Provides basic transfer characteristics for the semiconductor.  

              

                     Switching Characteristics

 

 

                           Reverse Recovery Waveform

Tested Parameters:

 

Test Symbol Parameter/Characteristics
Double-Pulse Test/Clamp td(on) Turn-on Delay Time
The time from VGS reaching 10% of its maximum level till VDS dropped to 90% of its initial level
tr Turn-on rise time
This is the time it takes for VDS to drop from 90% to 10% of its full swing. Note that this is effectively a falling edge. Nevertheless, the standard refers to this a rise time!
ton Turn-on time
The time it takes to turn-on the transistor. This is the sum of Turn-on delay time and Rise time
e(on) Turn-on energy
This the switching energy loss when turning on the transistor. This is calculated by integrating the switching power, which is the product of VDS and ID. The integration time is defined from ID reaching 10% of its final level to VDS dropping to 10%.
td(off)

Turn-off delay time
The time from VGS dropping to 90% of its initial level till VDS reached 10% of its final level
tf Turn-off rise time
This is the time it takes for VDS to rise from 10% to 90% of its full swing. Note that this is effectively a rising edge. Nevertheless, the standard refers to this a fall time!
toff Turn-off time
The time it takes to turn-off the transistor. This is the sum of Turn-off delay time and Fall time
e(off) Turn-off energy
This the switching energy loss when turning off the transistor. This is calculated by integrating the switching power, which is the product of VDS and ID. The integration time is defined from VDS reaching 10% of its final level to IDS dropping to 10%.
di/dt di/dt
dv/dt dv/dt
Rds(on) On-resistance
Id vs. t Switching Characteristics
Vds vs. t
Vgs vs. t
Ig vs. t
Clamped Vds vs. t
e vs.t
Id vs. Vds Switching locus
Reverse Recovery trr Reverse recovery time (also known as Reverse Recovery Integration Time)
Qrr Reverse recovery charge
Err Reverse recovery energy
Irr Maximum reverse recovery current
Id vs. t Reverse recovery current characteristics
Gate Charge Qg Total gate charge
Qgs(th) Threshold gate charge
Qgs(pl) Plateau gate charge
Qgd Gate drain charge
Vgs vs. t Gate charge curve
Multiple Tests Id vs. Vd Derived output characteristics

 

Additional Definitions

Symbol Measured Quantity Description
VDS Drain-Source Voltage

The drain to source voltage is directly measured using a Keysight 10076A 100:1 high voltage passive probe.

ID Drain Current The source current, which is practically identical to the drain current, is measured using a coaxial shunt. The PD1000-60002 Protection Probe acts as a 2:1 passive probe. However, its main purpose is to protect the oscilloscope against over voltages in case the shunt opens.
VGS Gate-Source Voltage The Gate-to-Source voltage is directly measured using a Keysight N2873A 10:1 Passive Probe. For a TO-247 3-pin (no Kelvin Source pin) device, the single-source pin uses a common ground for all passive probes.
IG Gate Current Gate Current is measured using a Keysight N2819A Differential Active Probe using the Gate Resistor (RG) as a shunt. The measurement must be floating and therefore a differential probe is used.
tz Tail Time
(IGBT only, not relevant for FET)		 When an IGBT begins to turn off, minority carriers contribute to internal recombination current. This is called the "tail current." Tail Current is the Collector current with a high VCS applied and is one of the significant contributors to switching loss.

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For IGBTs:

For IGBTs the Turn On measurements are defined according to IEC 60747-9:

Parameter Description Corresponding section in IEC 60747-9
Turn on delay td(on) Time between 10% VGEà 10% ICM 6.3.11
Turn on rise time tr Time between 10% ICMà 90% ICM 6.3.11
Turn on time ton ton=td(on)+tr 6.3.11
Turn on Energy e(on) Integral of VCE x IC x dt
(integration time ti: 10% VGEà VCE = 2%VCC) 		6.3.11
di/dt (on) Plot the derivate of the current between 10% and 90%
of ICM. Report the maximum. 		No spec available
dv/dt (on) Plot the derivate of the voltage between 90% and 10%
of VCE. Report the maximum. 		No spec available

 

For IGBTs the Turn Off measurements are defined according to IEC 60747-9:

Parameter Description Corresponding section in IEC 60747-9
Turn off delay td(off) Time between 90% VGEà 90%ICM 6.3.12
Turn off fall time tf Time between 90% ICMà 10% ICM 6.3.12
Tail time tz Time between 10% ICMà 2% ICM 6.3.12
Turn off time toff toff=td(off)+tf 6.3.12
Integration Time ti ti=td(off)+tf+tz 6.3.12
Turn off Energy e(off) Integral of VDS x ID x dt
(integration time ti: 90% VGEà 2% ICM) 		6.3.12
di/dt (off) Plot the derivate of the current between 90% and 10%
of ICM. Report the maximum. 		No spec available
dv/dt (off) Plot the derivate of the voltage between 10% and 90%
of VCE. Report the maximum. 		No spec available

 

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