SP619 Datasheet, PDF (4/7 Pages) Sipex Corporation – High Current Power Switch

The SP619 is a switch capable of handling
up to 800mA of current.
The SP619 is targeted as a for 5V USB
protection power distribution switch. And
can be used in general power distribution
applications where short circuits are likely
to be encountered.
Short circuit operation
When the SP619 enters a short circuit con-
dition, the switch is disabled. The output
of the SP619 will not restart until the out-
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enable pin can be used to re-enable the
SP619 into any load condition that is not
a fault condition. Refer to the truth table on
page 4 for more information on the differ-
ent SP619 switch states. The typical deac-
tivation time is about 2ms.
THEORY OF OPERATIION
inrush current that can be encountered.
At 6 volts in, the inrush current was about
250mA into a ^{100µF capacitor.}
Output Voltage Rise Time
The output voltage of the SP619 has an
output capacitance dependency on the
slope of VOUT. A simple RC circuit is cre-
ated when the switch is turned on.
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( ^V(t)=VO+VIN
-t
1-e^{RDS(ON) • COUT}
Where VO is initial Voltage condition typi-
cally 0V
VIN is the input voltage
RDS(ON) is the switch resistance
COUT is the output capacitance
For 4.2V VIN and 100µF output capacitance
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Enable
The enable pin allows easy control of the
SP619. The enable pin should not be en-
abled high prior to a voltage being pres-
ent on the input of the device. The enable
pin should not exceed the input voltage by
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ode. Doing so will affect the operation of
the SP619 and could damage the device.
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This resistor will pull the enable low when
an enable signal is not present. This pre-
vents the SP619 from falsely turning on.
The enable pin can also be used to restart
the part into a load condition that is high in
current. Please refer to the truth table on
page 4 for more details.
4.17
3.33
VOUT 2.5
1.67
0.83
0
0
0.33
0.67
1
1.33
1.67
2
time in uS
This is comparable to actual measured
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Inrush Current
The SP619 is a simple resistive switch.
When the switch is turned on into a highly
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April 2008 Rev L
SP619 High Current Power Switch
4
© 2008 EXAR Corporation