ISO7842_16 Datasheet, PDF (20/37 Pages) Texas Instruments – High-Performance, 8000-VPK Reinforced Quad-Channel Digital Isolator

ISO7842, ISO7842F
SLLSEJ0F – OCTOBER 2014 – REVISED APRIL 2016
www.ti.com
8.3.1.2 Safety Limiting Values
Safety limiting 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.
Table 6. Safety Limiting Values
PARAMETER
TEST CONDITIONS
R_θJA = 78.9°C/W, V_I = 5.5 V, T_J = 150°C, T_A = 25°C
I_S
Safety input, output, or supply
current
R_θJA = 78.9°C/W, V_I = 3.6 V, T_J = 150°C, T_A = 25°C
R_θJA = 78.9°C/W, V_I = 2.75 V, T_J = 150°C, T_A = 25°C
P_S Safety input, output, or total
power
R_θJA = 78.9°C/W, T_J = 150°C, T_A = 25°C
T_S Maximum safety temperature
MIN TYP
MAX
288
440
576
1584
150
UNIT
mA
mW
°C
The maximum safety temperature is the maximum junction temperature specified for the device. 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.
700
V_CC1 = V_CC2 = 2.75 V
600
V_CC1 = V_CC2 = 3.6 V
V_CC1 = V_CC2 = 5.5 V
500
400
300
200
100
0
0
50
100
150
200
Ambient Temperature (qC)
D014
Figure 15. Thermal Derating Curve for Safety Limiting
Current per VDE
1800
1600
Power
1400
1200
1000
800
600
400
200
0
0
50
100
150
200
Ambient Temperature (qC)
D015
Figure 16. Thermal Derating Curve for Safety Limiting
Power per VDE
20
Submit Documentation Feedback
Copyright © 2014–2016, Texas Instruments Incorporated
Product Folder Links: ISO7842 ISO7842F