0

100

200

300

400

500

600

700

0

50

100

150

200

Case Temperature - C

o

V

= V

= 5.5V

CC1

CC2

V

= V

= 2.7V

CC1

CC2

V

= V

= 3.6V

CC1

CC2

ISO7640FM, ISO7641FM

SLLSE89G – SEPTEMBER 2011 – REVISED JANUARY 2015

www.ti.com

8.3.3 Safety Limiting Values

Safety limiting intends to prevent potential damage to the isolation barrier upon failure of input or output circuitry.

A failure of the IO can allow low resistance to ground or the supply and, without current limiting, dissipate

sufficient power to overheat the die and damage the isolation barrier potentially leading to secondary system

failures.

Table 3. Safety Limiting Values

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

θJA = 72°C/W, VI = 5.5 V, TJ = 150°C, TA = 25°C

316

Safety input, output, or supply

IS

DW-16

θJA = 72°C/W, VI = 3.6 V, TJ = 150°C, TA = 25°C

482

mA

current

θJA = 72°C/W, VI = 2.7 V, TJ = 150°C, TA = 25°C

643

TS

Maximum case temperature

150

°C

The safety-limiting constraint is the absolute maximum junction temperature specified in the absolute maximum

ratings table. The power dissipation and junction-to-air thermal impedance of the device installed in the

application hardware determines the junction temperature. The assumed junction-to-air thermal resistance in the

Thermal Information table is that of a device installed on a High-K Test Board for Leaded Surface Mount

Packages. The power is the recommended maximum input voltage times the current. The junction temperature is

then the ambient temperature plus the power times the junction-to-air thermal resistance.

Figure 14. DW-16

θJC Thermal Derating Curve per DIN V VDE V 0884-10

24

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