SI8435 SILABS [Silicon Laboratories], SI8435 Datasheet - Page 20

• Manufacturer Part Number: SI8435
• Description: TRIPLE-CHANNEL DIGITAL ISOLATOR
• Manufacturer: SILABS [Silicon Laboratories]

Si8430/31/35
4. Layout Recommendations
Dielectric isolation is a set of specifications produced by the safety regulatory agencies from around the world that
describes the physical construction of electrical equipment that derives power from a high-voltage power system
such as 100–240 V
specifications places a very high voltage between the input power pins of a product and the user circuits and the
user touchable surfaces of the product. For the IEC relating to products deriving their power from the 220–240 V
power grids, the test voltage is 2500 V
There are two terms described in the safety specifications:
Figure 13 illustrates the accepted method of providing the proper creepage distance along the surface. For a
220–240 V application, this distance is 8 mm and the wide body SOIC package must be used. There must be no
copper traces within this 8 mm exclusion area, and the surface should have a conformal coating such as solder
resist. The digital isolator chip must straddle this exclusion area.
4.1. Supply Bypass
The Si843x requires a 0.1 µF bypass capacitor between V
should be placed as close as possible to the package.
20
Creepage—the distance along the insulating surface an arc may travel.
Clearance—the distance through the shortest path through air that an arc may travel.
AC
systems or industrial power systems. The dielectric test (or HIPOT test) given in the safety
AC
Figure 13. Creepage Distance
(or 3750 V
DC
Rev. 0.3
—the peak equivalent voltage).
DD1
and GND1 and V
DD2
and GND2. The capacitor