LM2931_05 Datasheet, PDF (1/18 Pages) National Semiconductor (TI) – Series Low Dropout Regulators

June 2005
LM2931
Series Low Dropout Regulators
General Description
The LM2931 positive voltage regulator features a very low
quiescent current of 1mA or less when supplying 10mA loads.
This unique characteristic and the extremely low input-output
differential required for proper regulation (0.2V for output cur-
rents of 10mA) make the LM2931 the ideal regulator for
standby power systems. Applications include memory stand-
by circuits, CMOS and other low power processor power
supplies as well as systems demanding as much as 100mA
of output current.
Designed originally for automotive applications, the LM2931
and all regulated circuitry are protected from reverse battery
installations or 2 battery jumps. During line transients, such
as a load dump (60V) when the input voltage to the regulator
can momentarily exceed the specified maximum operating
voltage, the regulator will automatically shut down to protect
both internal circuits and the load. The LM2931 cannot be
harmed by temporary mirror-image insertion. Familiar regu-
lator features such as short circuit and thermal overload pro-
tection are also provided.
The LM2931 family includes a fixed 5V output (±3.8% toler-
ance for A grade) or an adjustable output with ON/OFF pin.
Both versions are available in a TO-220 power package,
TO-263 surface mount package, and an 8-lead surface mount
package. The fixed output version is also available in the
TO-92 plastic and 6-Bump micro SMD packages.
Features
■ ^{Very low quiescent current}
■ ^{Output current in excess of 100 mA}
■ ^{Input-output differential less than 0.6V}
■ ^{Reverse battery protection}
■ ^{60V load dump protection}
■ ^{−50V reverse transient protection}
■ ^{Short circuit protection}
■ ^{Internal thermal overload protection}
■ ^{Mirror-image insertion protection}
■ ^{Available in TO-220, TO-92, TO-263, SO-8 or 6-Bump mi-}
cro SMD packages
■ ^{Available as adjustable with TTL compatible switch}
■ ^{See AN-1112 for micro SMD considerations}
Connection Diagrams
FIXED VOLTAGE OUTPUT
TO-220 3-Lead Power Package
TO-263 Surface-Mount Package
Front View
525406
8-Pin Surface Mount
525411
Top View
525412
Side View
TO-92 Plastic Package
525407
*NC = Not internally connected. Must be electrically isolated from the rest of
the circuit for the micro SMD package.
Top View
525408
Bottom View
© 2006 National Semiconductor Corporation 5254
www.national.com