HIP4082EVAL Intersil, HIP4082EVAL Datasheet - Page 8

• Manufacturer Part Number: HIP4082EVAL
• Description: EVAL BOARD FET DRIVER HIP4082
• Manufacturer: Intersil
• Type: FET Driverr

Specifications of HIP4082EVAL

• Contents: Fully Assembled Evaluation Board
• For Use With/related Products: HIP4082
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

trip level based upon the divider action of R
output of U
voltage half-bridge drivers, disabling them.
Once tripping has occurred, reset must be accomplished by
removing input voltage to the eval-board, as R
enough hysteresis such that even after the load current is
dropped to zero (no signal at the SHUNT resistor), the
voltage on the positive summing junction of U
that on the negative summing junction.
Overtemperature Protection
Resistors R
overtemperature function. Overtemperature does not shut
down the eval-board as in the case of overcurrent. Instead,
the duty-cycle of the output voltage waveform is reduced,
thereby reducing the RMS output voltage. This is
accomplished by faking the voltage control function into
thinking that the input voltage is higher than it really is.
When the thermistor, RT1, temperature increases, its
resistance decreases and the negative summing junction
voltage on pin 6 of U4B decreases. Eventually, when it falls
below the voltage on the positive summing junction, the
output, pin 7, of U4B rises. The voltage on the positive
summing junction is determined by the bias voltage and the
ratio of R11 to R12. The temperature at which this happens
is determined by the negative resistance characteristics of
the thermistor chosen and its temperature. RT1 is attached
by epoxy cement to one of the primary-side MOSFETs.
Diode D4, blocks the voltage on the output pin 7 of U4B from
affecting the inverter output voltage until after the
overtemperature condition has been reached.
Snubbers
A DC bus voltage snubber has been employed to control or
reduce transients across the bridge which might lead to
breakdown failure in either the MOSFETs or the HIP2500
drivers, or both. The bus voltage transients are snubbed by
the bus snubber comprised of resistor, R
C
Reference 2.
Conclusion
A simple, cost-effective solution to designing low to medium
voltage DC-to-AC inverters using the HIP4082 H-Bridge
Gate Driver has been shown using the HIP4082 DC/AC
Evaluation PC Board as a demonstration vehicle. Other
approaches using the same HIP4082 can certainly be
imagined and implemented with success.
Hopefully this application note will assist the designer in
getting started on his or her own design. This same HIP4082
IC can also be used in AC-to-DC converters, such as those
used in various motor controls and other high performance
DC voltage controllers.
23
. A good reference on snubber design is found in
7A
10
goes to the SD input of both HIP2500 high
- R
12
, R
14
, R
T1
8
and diode D
34
4
29
and capacitor,
, provide the
7A
28
and R
will exceed
provides
Application Note 9611
32
. The
WARNING
A neon lamp was placed across the output of the
inverter in order to warn users of the presence of HIGH
VOLTAGE AND POTENTIAL SHOCK HAZARD.