Datasheet
-470.02
R
(RSET)
V - 0.00314
(OFF)
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TPS2410
TPS2411
SLVS727C – NOVEMBER 2006 – REVISED JUNE 2009 ..................................................................................................................................................
www.ti.com
RSET: A resistor connected from this pin to GND sets the MOSFET fast turn-off comparator threshold. The
threshold is slightly positive when the RSET pin is left open. Current drawn by the resistor programs the turn-off
voltage to increasing negative values. The TPS2411 must have a negative threshold programmed to avoid an
unstable condition at light load. The expression for R(RSET) in terms of the fast comparator-trip voltage, V
(OFF)
,
follows.
The units of the numerator are (V × V/A). V
(OFF)
is positive for V
(A)
greater than V
(C)
, V
(OFF)
is less than 3 mV, and
R
(RSET)
is in ohms.
RSVD: Connect to ground.
STAT: STAT is a multifunction pin. STAT outputs the status of the GATE pin drive. The internal weak pull-up
pulls STAT to V
DD
when GATE is being driven high and V
(GATE)
is 0.4 V greater than V
(A)
. If STAT is externally
pulled below V
DD
/2 while the pin would otherwise be high, the turnoff threshold is shifted negative (~157 mV)
from the RSET programmed value. Interconnecting the STAT pins of redundant devices, in systems that
normally have both devices on, reduces the likelihood that both devices will turn off in the event of a transient.
See the FUNCTIONAL BLOCK DIAGRAM, INPUT ORing and STAT, and Figure 13 .
UV, OV, PG: These signals are used to monitor an input voltage for proper range. PG sinks current to GND if UV
is below its threshold, OV is above its threshold, or V
DD
is below the internal UVLO. PG may not be valid when
V
DD
is below the UVLO.
A high input on OV causes GATE to be driven low. UV does not effect the MOSFET operation. This permits OV
to be used as an active-high disable.
OV and UV should be connected to ground when not used, and PG may be left open. Multiple PG pins to be wire
ORed using a common pull-up resistor.
V
DD
: V
DD
is the primary supply for the gate drive charge pump and other internal circuits. This pin must be
connected a source that is 3 V or greater when the external MOSFET is to be turned on. V
DD
may be greater or
lower than the controlled bus voltage.
A 0.01- µ F bypass capacitor, or 10- Ω and a 0.0 1- µ F filter, is recommended because charge pump currents are
drawn through V
DD
.
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