Unformatted text preview: m primary side to
the secondary side.
3. Several thousand volts of isolation can be built in
between windings by proper design and layouts.
The disadvantages of using transformers for Gate
1. They can be used only for time varying signals.
2. It is difficult to implement DESAT protection
Two examples of gate Drive circuits, using
transformers follow. In Fig. (11), a phase shift
controller outputs its signals to the IXD_404 Dual
Drivers, which in-turn, feed the transformers. The
secondary windings of these transformers are
coupled to the Gates of upper and lower MOSFETs IXAN0009 in an “H” Bridge topology. Fig. (14) shows
another transformer coupled Gate Drive circuit
employing DC restore technique to maintain
same wave shape of original signal with added
feature of -ve bias offered using a Zener in
series with a fast diode across secondary.
4.0 DESIRABLE SPECIFICATIONS AND
FEATURES OF ANY LOW AND HIGH SIDE
DRIVER PAIRS, SUCH AS IXBD4410 AND
1. Under voltage and over voltage lockout
protection for Vcc ;
2. dV /dt immunity of greater than ± 50 V/ns;
3. Galvanic isolation of 1200 Volts (or greater)
low side and high side;
4. On-chip negative gate-drive supply to ensure
MOSFET/IGBT turn-off even in electrically
5. CMOS/HCMOS compatible inputs with
6. < 20 ns rise and fall times with 1000 pf load
and <100 ns rise and fall times with 10000 pf
7. <100 ns of propagation delay;
8. >2 Ampere peak output Drive Capability;
9. Automatic shutdown of output in response to
over current and/or short -circuit;
10. Protection against cross conduction between
upper and lower MOSFET/IGBT;
11. Logic compatible fault indication from both
low and high-side drivers.
A suggested wiring diagram, making use of such
a high/low side driver pair is shown in Fig. (4).
This diagram is for a phase leg of MOSFETs or
IGBTs. Likewise, the wiring diagram is to be
repeated for each phase leg and hence one
needs two such circuits for “H” Bridge and three
such circuits for 3-Phase Bridge topologies
As can be seen in this schematic, to obtain
galvanic isolation, it uses one ferrite core
transformer for sending drive signals to
IXBD4411 and another ferrite core tran...
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This note was uploaded on 01/15/2014 for the course ECE 624 taught by Professor Staff during the Winter '08 term at Ohio State.
- Winter '08