©2001 Fairchild Semiconductor Corporation 7www.fairchildsemi.com
HGTG18N120BN Rev. C1
Handling Precautions for IGBTs
Insulated Gate Bipolar Transistors are susceptible to gate-insulation
damage by the electrostatic discharge of ener gy 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 taken:
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 wristba nd.
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 r ating 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 th at le ave 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 no t have an internal
monolithic Zener diode from gate to emitter. If gate protection
is required an external Zener is recommended.
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; whicheve r
is smaller at each point. T he information is based on measurements
of a typical device and is bounded by the maximum rated junction
temperature.
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 21. 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 loaded condition.
fMAX2 is defined by fMAX2 = (PD - PC)/(EOFF + EON). The
allowable dissipation (PD) is defined by PD = (TJM - TC)/RθJC. T he
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=(V
CE xI
CE)/2.
EON and EOFF are defined in the switching waveforms shown in
Figure 21. EON is the in tegral of the instantaneous power l oss (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).
HGTG18N120BN