VB027(6)-12 STMicroelectronics, VB027(6)-12 Datasheet - Page 6

• Manufacturer Part Number: VB027(6)-12
• Description: IC DVR PWR COIL 300V PENTAWATTHV
• Manufacturer: STMicroelectronics
• Series: VIPower™r

Specifications of VB027(6)-12

• Current - Output: 9A
• Voltage - Supply: 4.5 V ~ 5.5 V
• Mounting Type: Through Hole
• Package / Case: Pentawatt-5 HV (Bent and Staggered Leads)
• Product: Electronic Ignition Drivers
• Mounting Style: Through Hole
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Operating Temperature: -
• Applications: -
• Number Of Outputs: -
• Voltage - Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

APPLICATION NOTE
D. Dynamic Bias of the P-type buried layer
At turn-on, when the current in the primary coil is
close to zero, it is evident that the effect of the
oscillation of the secondary current is due, mainly,
to the ignition coil parasitic element. An oscillating
current is added to the primary magnetizing current
and it forces, during its negative phase, the collector-
emitter voltage to reverse, thus directly biasing the
p-buried-layer/n-epi junction. This effect could lead
to excessive sinking current from Vd and to
undesirable effects on the control circuit because of
failure of the insulation. A patent pending circuit has
been designed to perform a dynamic bias of the p-
type buried layer, whose voltage is forced to follow
Figure 8. Dynamic bias of p-type buried layer
Figure 9. Standard package (TO-220 - 5 leads) and top view of the device
6/7
I
coil
the collector voltage when it becomes negative.
Figure 8 shows the operation of this circuit.
E. Power Darlington
In the horizontal layout, shown in Figure 9, the power
Darlington is, in some respects, very similar to a
standard discrete transistor. The main differences
are in a novel, patent pending, vertical structure, the
cross section of which is shown in Figure 10. The
deep-base structure and the original layout of the
emitter and base ballast resistors have allowed a
considerable increase in the current density and in
the Safe Operating Areas of the device. The device
has an energy handling capability of up to 1 Joule.
V
V
clamp
p - layer