February 1995
LM140L/LM340L Series 3-Terminal Positive Regulators
General Description
The LM140L series of three terminal positive regulators is
available with several fixed output voltages making them
useful in a wide range of applications. The LM140LA is an
improved version of the LM78LXX series with a tighter out-
put voltage tolerance (specified over the full military temper-
ature range), higher ripple rejection, better regulation and
lower quiescent current. The LM140LA regulators have
becomes too high for the heat sinking provided, the thermal
shut-down circuit takes over, preventing the IC from over-
heating.
For applications requiring other voltages, see LM117L Data
Sheet.
Features
Y
g
2%
V
specification, 0.04%/V line regulation, and
OUT
Line regulation of 0.04%/V
0.01%/mA load regulation. When used as a zener diode/re-
sistor combination replacement, the LM140LA usually re-
sults in an effective output impedance improvement of two
orders of magnitude, and lower quiescent current. These
regulators can provide local on card regulation, eliminating
the distribution problems associated with single point regu-
lation. The voltages available allow the LM140LA to be used
in logic systems, instrumentation, Hi-Fi, and other solid state
electronic equipment. Although designed primarily as fixed
voltage regulators, these devices can be used with external
components to obtain adjustable voltages and currents.
Y
Load regulation of 0.01%/mA
Y
e
g
Output voltage tolerances of 2% at T
25 C and
§
j
g
g
4% over the temperature range (LM140LA)
3% over the temperature range (LM340LA)
Y
Y
Y
Y
Y
Output current of 100 mA
Internal thermal overload protection
Output transistor safe area protection
Internal short circuit current limit
Available in metal TO-39 low profile package
(LM140LA/LM340LA) and plastic TO-92 (LM340LA)
The LM140LA/LM340LA are available in the low profile
metal three lead TO-39 (H) and the LM340LA are also avail-
able in the plastic TO-92 (Z). With adequate heat sinking the
regulator can deliver 100 mA output current. Current limiting
is included to limit the peak output current to a safe value.
Safe area protection for the output transistor is provided to
limit internal power dissipation. If internal power dissipation
Output Voltage Options
LM140LA-5.0
LM140LA-12
LM140LA-15
5V
12V
15V
LM340LA-5.0
LM340LA-12
LM340LA-15
5V
12V
15V
Connection Diagrams
TO-39 Metal Can Package (H)
TL/H/7782–2
Bottom View
Order Number LM140LAH-5.0, LM140LAH-5.0/883, LM140LAH-12,
LM140LAH-12/883, LM140LAH-15, LM140LAH-15/883, LM340LAH-5.0, LM340LAH-12 or LM340LAH-15
See NS Package Number H03A
TO-92 Plastic Package (Z)
TL/H/7782–3
Bottom View
Order Number LM340LAZ-5.0, LM340LAZ-12 or LM340LAZ-15
See NS Package Number Z03A
C
1995 National Semiconductor Corporation
TL/H/7782
RRD-B30M115/Printed in U. S. A.