10.2.1 Design Requirements

To design with this device, use the parameters listed in Table 10-1.

Table 10-1. Design Parameters

PARAMETER

VALUE

Input voltage

3 V to 5.5 V

0.01 µF to 20 µF

0.01 µF to 20 µF

decoupling capacitors typically provide better noise and ripple performance. Although a 10-µF capacitor is

grounds are strongly recommended to achieve the best performance.

10.2.2 Insulation Lifetime

Insulation lifetime projection data is collected by using industry-standard Time Dependent Dielectric Breakdown

(TDDB) test method. In this test, all pins on each side of the barrier are tied together creating a two-terminal

device and high voltage applied between the two sides; See Figure 10-2 for TDDB test setup. The insulation

breakdown data is collected at various high voltages switching at 60 Hz over temperature. For reinforced

insulation, VDE standard requires the use of TDDB projection line with failure rate of less than 1 part per million

(ppm). Even though the expected minimum insulation lifetime is 20 years at the specified working isolation

voltage, VDE reinforced certification requires additional safety margin of 20% for working voltage and 87.5% for

lifetime which translates into minimum required insulation lifetime of 37.5 years at a working voltage that's 20%

higher than the specified value.

Figure 10-3 shows the intrinsic capability of the isolation barrier to withstand high voltage stress over its lifetime.

DUT

Vcc 2

Vcc 1

GND 1

GND 2

A

Ovenat150°C

TimeCounter

> 1 mA

V

S

Figure 10-2. Test Setup for Insulation Lifetime Measurement

ISOW7741

SLLSFK1 – DECEMBER 2020

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