LM320L/LM79LXXAC Series
3-Terminal Negative Regulators
General Description
The LM320L/LM79LXXAC dual marked series of 3-terminal
negative voltage regulators features fixed output voltages of
−5V, −12V, and −15V with output current capabilities in
excess of 100mA. These devices were designed using the
latest computer techniques for optimizing the packaged IC
thermal/electrical performance. The LM79LXXAC series,
even when combined with a minimum output compensation
capacitor of 0.1µF, exhibits an excellent transient response,
a maximum line regulation of 0.07% V
load regulation of 0.01% V
The LM320L/LM79LXXAC series also includes, as selfprotection circuitry: safe operating area circuitry for output
transistor power dissipation limiting, a temperature independent short circuit current limit for peak output current limiting,
and a thermal shutdown circuit to prevent excessive junction
temperature. Although designed primarily as fixed voltage
regulators, these devices may be combined with simple
external circuitry for boosted and/or adjustable voltages and
currents. The LM79LXXAC series is available in the 3-lead
O
/mA.
/V, and a maximum
O
February 2005
TO-92 package, 8-lead SOIC package, and the 6-Bump
micro SMD package. The LM320L series is available in the
3-lead TO-92 package.
For output voltage other than −5V, −12V and −15V, the
LM137L series provides an output voltage range from 1.2V
to 47V.
Features
n Preset output voltage error is less than±5% overload,
line and temperature
n Specified at an output current of 100mA
n Easily compensated with a small 0.1µF output
capacitor
n Internal short-circuit, thermal and safe operating area
protection
n Easily adjustable to higher output voltages
n Maximum line regulation less than 0.07% V
n Maximum load regulation less than 0.01% V
n See AN-1112 for micro SMD considerations
OUT
OUT
/V
/mA
LM320L/LM79LXXAC Series 3-Terminal Negative Regulators
Typical Applications
Fixed Output Regulator
*Required if the regulator is located far from the power supply filter. A 1µF
aluminum electrolytic may be substituted.
*
*
Required for stability. A 1µF aluminum electrolytic may be substituted.
3-Pin TO-92LM79L05ACZ320L79L051800 Units Per BoxZ03A
LM79L12ACZ320L79L121800 Units Per Box
LM79L15ACZ320L79L151800 Units Per Box
6-Bump
micro SMD
LM79L15ACTLXTPB250 Units Tape and ReelTLA06AMA
LM79L05ACTLX3k Units Tape and Reel
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Page 3
LM320L/LM79LXXAC
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Input Voltage
= −5V, −12V, −15V−35V
V
O
Operating Temperature Range0˚C to +70˚C
Maximum Junction Temperature+125˚C
Storage Temperature Range−55˚C to +150˚C
Lead Temperature
(Soldering, 10 sec.)260˚C
Internal Power Dissipation (Note 2)Internally Limited
Electrical Characteristics (Note 3)
TA= 0˚C to +70˚C unless otherwise noted.
Output Voltage−5V−12V−15V
Input Voltage (unless otherwise noted)−10V−17V−20VUnits
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits.
Note 2: Thermal resistance of Z package is 60˚C/W θ
maximum junction temperature shall not exceed 125˚C on electrical parameters.
Note 3: To ensure constant junction temperature, low duty cycle pulse testing is used.
LM320L/LM79LXXAC Series 3-Terminal Negative Regulators
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves
the right at any time without notice to change said circuitry and specifications.
For the most current product information visit us at www.national.com.
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