Datasheet

I
SCP(min)
+
V
ILIM(min)
R
DS(onMAX)
I
SCP(max)
+
V
ILIM(max)
R
DS(onMIN)
Relative Change
−50 −25
0
25 50
75 100
0.7
0.8
0.9
1.0
1.1
1.3
1.2
Short Circuit
Threshold
Voltage
FET
Resistance
T
J
− Junction Temperature − °C
TPS40190
SLUS658C –JULY 2005–REVISED JULY 2012 www.ti.com
RELATIVE SHORT CIRCUIT THRESHOLD CHANGE
vs
TEMPERATURE
Figure 3.
Table 1. Short Circuit Threshold Voltage Selection
Short Circuit Protection Nominal Current Limit
Resistance Voltage
R
COMP
(kΩ) V
ILIM
(mV)
10.8 to 13.2 460
OPEN 320
3.6 to 4.4 160
The range of short circuit current thresholds that can be expected is given by Equation 1 and Equation 2.
(1)
where
• I
SCP
is the short circuit current
• V
ILIM
is the short circuit threshold
• R
DS(on)
is the channel resistance of the high-side MOSFET (2)
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