Test Circuit and Waveforms
RG = 50Ω
L = 2mH
VDD = 480V
FIGURE 19. INDUCTIVE SWITCHING TEST CIRCUIT
Handling Precautions for IGBTs
Insulated Gate Bipolar Transistors are susceptible to
gate-insulation damage by the electrostatic discharge of
energy through the devices. When handling these devices,
care should be exercised to assure that the static charge
built in the handler’s body capacitance is not discharged
through the device. With proper handling and application
procedures, however, IGBTs are currently being extensively
used in production by numerous equipment manufacturers in
military, industrial and consumer applications, with virtually
no damage problems due to electrostatic discharge. IGBTs
can be handled safely if the following basic precautions are
1. Prior to assembly into a circuit, all leads should be kept
shorted together either by the use of metal shorting
springs or by the insertion into conductive material such
as “ECCOSORBD™ LD26” or equivalent.
2. When devices are removed by hand from their carriers,
the hand being used should be grounded by any suitable
means - for example, with a metallic wristband.
3. Tips of soldering irons should be grounded.
4. Devices should never be inserted into or removed from
circuits with power on.
5. Gate Voltage Rating - Never exceed the gate-voltage
rating of VGEM. Exceeding the rated VGE can result in
permanent damage to the oxide layer in the gate region.
6. Gate Termination - The gates of these devices are
essentially capacitors. Circuits that leave the gate open-
circuited or floating should be avoided. These conditions
can result in turn-on of the device due to voltage buildup
on the input capacitor due to leakage currents or pickup.
7. Gate Protection - These devices do not have an internal
monolithic Zener diode from gate to emitter. If gate
protection is required an external Zener is recommended.
FIGURE 20. SWITCHING TEST WAVEFORMS
Operating Frequency Information
Operating frequency information for a typical device
(Figure 3) is presented as a guide for estimating device
performance for a specific application. Other typical
frequency vs collector current (ICE) plots are possible using
the information shown for a typical unit in Figures 5, 6, 7, 8, 9
and 11. The operating frequency plot (Figure 3) of a typical
device shows fMAX1 or fMAX2; whichever is smaller at each
point. The information is based on measurements of a
typical device and is bounded by the maximum rated
fMAX1 is defined by fMAX1 = 0.05/(td(OFF)I+ td(ON)I).
Deadtime (the denominator) has been arbitrarily held to 10%
of the on-state time for a 50% duty factor. Other definitions
are possible. td(OFF)I and td(ON)I are defined in Figure 20.
Device turn-off delay can establish an additional frequency
limiting condition for an application other than TJM. td(OFF)I
is important when controlling output ripple under a lightly
fMAX2 is defined by fMAX2 = (PD - PC)/(EOFF + EON). The
allowable dissipation (PD) is defined by PD = (TJM - TC)/RθJC.
The sum of device switching and conduction losses must
not exceed PD. A 50% duty factor was used (Figure 3) and
the conduction losses (PC) are approximated by
PC = (VCE x ICE)/2.
EON and EOFF are defined in the switching waveforms
shown in Figure 20. EON is the integral of the instantaneous
power loss (ICE x VCE) during turn-on and EOFF is the
integral of the instantaneous power loss (ICE x VCE) during
turn-off. All tail losses are included in the calculation for
EOFF; i.e., the collector current equals zero (ICE = 0).
©2001 Fairchild Semiconductor Corporation
HGTP7N60B3D, HGT1S7N60B3DS Rev. B