Safety limiting(1) intends to minimize potential damage to the isolation barrier upon failure of input or output circuitry. A failure of the I/O 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.
PARAMETER |
TEST CONDITIONS |
MIN |
TYP |
MAX |
UNIT |
IS |
Safety input, output, or supply current |
RθJA = 212°C/W,
VI = 5.5 V, TJ = 170°C, TA = 25°C, see Section 6.3 |
|
|
124 |
mA |
RθJA =
212°C/W, VI = 3.6 V, TJ = 170°C, TA = 25°C, see Section 6.3 |
|
|
190 |
TS |
Safety temperature |
|
|
|
150 |
°C |
(1) The safety-limiting constraint is the maximum junction temperature specified in the data sheet. 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 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.