PDP Power Devices characteristics

AN2503

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4.2

Driving section

Driving section devices range from gate driver devices to input buffer ones. Gate driver

function is carried out by a gate driver IC and a push pull amplifier.

Driving section can be split in:

●

Gate driver section: L6385 or L6388

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Push pull section: STS01DTP06

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Input buffer section 74VHCT541

4.3

Gate driver devices

ST offers the widest series among the High Voltage Half-Bridge Gate Drivers (the L638x

series), manufactured with BCD"OFF-LINE" technology. They are able to work in

applications with with voltages to 600 V. In the L638x series the two selected drivers are the

L6388 [16.] and the L6385 [17.], which can drive two Power MOSFETs or IGBTs, one high-

side and one low-side, in a Half-Bridge or different topology. L6388 is especially effective in

applications where logic input must be compatible with 3.3 V Logic. Another key feature of

the L6388 is that it provides effective anti-shoot-through circuitry which prevents two Power

MOSFETs or IGBTs from being turned ON at the same time. This is achieved by introducing

a 200 ns time interval, a "dead time" between the moment one of the components is turned

OFF and the other is turned ON. L6385 is able to drive asymmetrical half bridge, but its

logic input is not compatible with 3.3V Logic.

The main features of these HV Gate Drivers are:

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dV/dt immunity +- 50 V/nsec in full temperature range

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Driver current capability:

–

400 mA source

–

650 mA sink

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Switching time 50/30 nsec rise/fall with 1 nF load

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Under voltage lock-out on lower and upper driving section

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Internal bootstrap diode

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Outputs in phase with inputs

Due to different characteristics, the topologies used in Energy Recovery Circuit and Sustain

Circuit depend on the driver used as shown in Figure 24 and Figure 25.