AN1596 Datasheet, PDF (1/24 Pages) STMicroelectronics – Today’s automotive market requires a continuous increasing

AN1596
®
- APPLICATION NOTE
VIPower: HIGH SIDE DRIVERS FOR AUTOMOTIVE
V. Graziano - L. Guarrasi - A. Pavlin
INTRODUCTION
Today’s automotive market requires a continuous increasing of complexity and reliability in the electronic
systems. To achieve this, the concept of the automotive systems is more and more based on micro
controllers architecture driving integrated monolithic circuits that include a power stage, control, driving
and protection circuits on the same chip. Vertical Intelligent Power, a STMicroelectronics patented
technology, established over 13 years ago, uses a fabrication process which allows the integration of
complete digital and/or analog control circuits driving a vertical power transistor on the same chip. The
VIPower M0 technology used for making High Side Drivers (HSDs) produces a monolithic silicon chip,
which combines control and protection circuitry with a standard power MOSFET structure where the
power stage current flows vertically through the silicon (see figure 1).
Figure 1: M0 chip structure
Driving circuitry
Enhancement and depletion NMOS
Power stage
VDMOS
p - well
n - type epilayer
n + substrate
Power stage output
The evolution of M0 technology made the drastic reduction of die size and of the resistance of devices
possible during conduction as well; each generation has seen a significant (from 40% to over 50%)
decrease in specific on-resistance and this translates into die size reduction, smaller packages, reduced
power dissipation and hence cost effective solutions. The third generation - the M0-3 - is in production
while STMicroelectronics is now developing the M0-4 and M0-5 technologies which will allow to achieve
less than 5mΩ R_DS(on) in a PowerSO-10 package. High Side Drivers, with their integrated extra features
are power switches that can manage high currents and work up to about 36V supply voltage. They only
require a simple TTL logic input and incorporate a diagnostic output to the micro-controller. They can
drive an inductive load without the need for a freewheeling diode. For complete protection the devices
have an over-temperature sensing circuit that will shut the chip down under over-temperature conditions.
Due to the aggressive automotive environment, High Side Drivers are designed to work from -40°C to
+150°C. They also have an under-voltage shutdown feature. Each application exerts an external
November 2002
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