Detailed description, Regulator, Thermal protection – Rainbow Electronics MAX15007 User Manual
Page 9: Output short-circuit current limit
MAX15006/MAX15007
40V, Ultra-Low Quiescent-Current
Linear Regulators in 6-Pin TDFN/8-Pin SO
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9
Detailed Description
The MAX15006/MAX15007 high-voltage linear regula-
tors operate over a 4V to 40V input voltage range.
These devices guarantee 50mA load drive, and offer
preset output voltages of +3.3V or +5V. Thermal shut-
down and short-circuit protection prevent damage dur-
ing overtemperature and overcurrent conditions. The
MAX15007 includes an enable input (EN) allowing the
regulators to be turned on/off using a logic-level volt-
age. Driving EN high turns on the device while driving
EN low places the device in a low-power shutdown
mode. In shutdown, the supply current is reduced to
3µA (typ). The MAX15006/MAX15007 operate over the
-40°C to +125°C automotive temperature range. All
devices are available in thermally enhanced 6-pin
TDFN and 8-pin SO packages capable of dissipating
1.904W and 1.860W at T
A
= +70°C, respectively.
Regulator
The regulator accepts an input voltage from 4V to 40V.
The MAX15006A/MAX15007A have a fixed 3.3V output
voltage while the MAX15006B/MAX15007B offer a fixed
5V output voltage.
EN Input (MAX15007 Only)
EN is an active-high, logic-level enable input that turns
the device on or off. Drive EN high to turn the device
on. An internal 0.5µA pulldown current keeps the
MAX15007 in shutdown mode when driven by a three-
state driver in high-impedance mode, or an open-drain
driver. While in shutdown, the device consumes only
3µA (typ). EN withstands voltages up to 40V, allowing it
to be driven by high input level voltages or connected
to IN for always-on operation.
Thermal Protection
When the junction temperature exceeds +165°C, an
internal thermal sensor turns the pass transistor off, and
allows the device to cool. The thermal sensor turns the
pass transistor on again after the junction temperature
cools by 20°C. This results in a cycled output during
continuous thermal-overload conditions. Thermal pro-
tection protects the MAX15006/MAX15007 in the event
of fault conditions. Operation at T
J
= +150°C without
going into thermal shutdown is not guaranteed. Use
Figures 3a and 3b to determine the minimum guaran-
teed output current.
Output Short-Circuit Current Limit
The MAX15006/MAX15007 feature a 175mA current
limit. The output can be shorted to GND for an indefi-
nite period of time without damage to the device.
During a short circuit, the power dissipated across the
pass transistor can quickly heat the device. When the
die temperature reaches +165°C, the MAX15006/
MAX15007 shut down and automatically restart after
the die temperature cools by 20°C.
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9
MAX15006 fig03a
AMBIENT TEMPERATURE (
°C)
OUTPUT CURRENT (mA)
125
120
110 115
90 95 100 105
85
5
10
15
20
25
30
35
40
45
50
55
0
80
130
V
IN
= 26V, V
OUT
= 5V
V
IN
= 18V, V
OUT
= 5V
V
IN
= 18V,
V
OUT
= 3.3V
V
IN
= 26V, V
OUT
= 3.3V
Figure 3a. Minimum Output Current vs. Ambient Temperature
(6-Pin TDFN-EP)
MAX15006 fig03b
AMBIENT TEMPERATURE (
°C)
OUTPUT CURRENT (mA)
125
120
110 115
90 95 100 105
85
5
10
15
20
25
30
35
40
45
50
55
0
80
130
V
IN
= 26V, V
OUT
= 5V
V
IN
= 18V, V
OUT
= 5V
V
IN
= 18V,
V
OUT
= 3.3V
V
IN
= 26V, V
OUT
= 3.3V
Figure 3b. Minimum Output Current vs. Ambient Temperature
(8-Pin SO-EP)