Zhb6790, Thermal characteristics, Transient thermal resistance – Diodes ZHB6790 User Manual
Page 2: Derating curve

THERMAL CHARACTERISTICS
PARAMETER
SYMBOL
VALUE
UNIT
Total Power Dissipation at T
amb
= 25°C*
Any single transistor on
Q1 and Q3 on or Q2 and Q4 on equally
P
tot
1.25
2
W
W
Derate above 25°C*
Any single transistor on
Q1 and Q3 on or Q2 and Q4 on equally
10
16
mW/ °C
mW/ °C
Thermal Resistance - Junction to Ambient*
Any single transistor on
Q1 and Q3 on or Q2 and Q4 on equally
100
62.5
°C/ W
°C/ W
ZHB6790
100us
Pulse Width
Transient Thermal Resistance
0
D=1
D=0.2
D=0.1
D=0.05
D=0.5
Single Pulse
D=t1
tP
t1
tP
1ms 10ms 100ms
1s
10s
100s
20
40
60
80
100
Single Pulse
Transient Thermal Resistance
Pulse Width
t1
1ms
100us
0
10ms
tP
D=t1
tP
1s
100ms
D=0.2
D=0.05
D=0.1
10s
D=0.5
D=1
100s
10
20
30
40
50
60
T - Temperature (°C)
0
0.5
0
20
1.5
1.0
2.0
Derating curve
40
60
80 100
140
120
160
Single Transistor "On"
Q1 and Q3 or Q2 and Q4 "On"
Pd v Pcb Area Comparison
0.1
0.1
10
Pcb Area (inches squared)
1
10
1
Dual Transistors
Single Transistor
Dual Transistors
Single Transistor
Full Copper
Minimum
Copper
* The power which can be dissipated assuming the device is mounted in a typical manner on a PCB
with copper equal to 2 inches square.
"Two devices on" is the standard operating condition for the bridge. Eg. opposing NPN/PNP pairs
rurned on.