Datasheet

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0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 4 4.4 4.8 5.2 5.6
VIN (V)
Ron (mΩ)
VBIAS = 2.5V
VBIAS = 3.3V
VBIAS = 3.6V
VBIAS= 4.2V
VBIAS = 5V
VBIAS = 5.5V
Temperature=25C, IOUT=−200mA
G062
TPS22965
SLVSBJ0A –AUGUST 2012–REVISED AUGUST 2013 www.ti.com
APPLICATION INFORMATION
ON/OFF CONTROL
The ON pin controls the state of the switch. Asserting ON high enables the switch. ON is active high and has a
low threshold, making it capable of interfacing with low-voltage signals. The ON pin is compatible with standard
GPIO logic thresholds. It can be used with any microcontroller with 1.2V or higher GPIO voltage. This pin cannot
be left floating and must be driven either high or low for proper functionality.
INPUT CAPACITOR (OPTIONAL)
To limit the voltage drop on the input supply caused by transient in-rush currents when the switch turns on into a
discharged load capacitor or short-circuit, a capacitor needs to be placed between VIN and GND. A 1-µF ceramic
capacitor, C
IN
, placed close to the pins, is usually sufficient. Higher values of C
IN
can be used to further reduce
the voltage drop during high current applications. When switching heavy loads, it is recommended to have an
input capacitor about 10 times higher than the output capacitor to avoid excessive voltage drop.
OUTPUT CAPACITOR (OPTIONAL)
Due to the integrated body diode in the NMOS switch, a C
IN
greater than C
L
is highly recommended. A C
L
greater than C
IN
can cause V
OUT
to exceed V
IN
when the system supply is removed. This could result in current
flow through the body diode from V
OUT
to V
IN
. A C
IN
to C
L
ratio of 10 to 1 is recommended for minimizing V
IN
dip
caused by inrush currents during startup, however a 10 to 1 ratio for capacitance is not required for proper
functionality of the device. A ratio smaller than 10 to 1 (such as 1 to 1) could cause slightly more V
IN
dip upon
turn-on due to inrush currents. This can be mitigated by increasing the capacitance on the CT pin for a longer
rise time (see below).
V
IN
and V
BIAS
VOLTAGE RANGE
For optimal R
ON
performance, make sure V
IN
≤ V
BIAS
. The device will still be functional if V
IN
> V
BIAS
but it will
exhibit R
ON
greater than what is listed in the ELECTRICAL CHARACTERISTICS table. See Figure 3 for an
example of a typical device. Notice the increasing R
ON
as V
IN
exceeds V
BIAS
voltage. Be sure to never exceed
the maximum voltage rating for V
IN
and V
BIAS
.
Figure 3. R
ON
vs. V
IN
(V
IN
> V
BIAS
)
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