LM317LM/NOPB National Semiconductor, LM317LM/NOPB Datasheet - Page 7

• Manufacturer Part Number: LM317LM/NOPB
• Description: IC REG POSITIVE ADJ 8-SOIC
• Manufacturer: National Semiconductor
• Type: Voltage Regulatorr

Specifications of LM317LM/NOPB

• Regulator Topology: Positive Adjustable
• Voltage - Output: 1.2 ~ 37 V
• Voltage - Input: 4.2 ~ 40 V
• Number Of Regulators: 1
• Current - Output: 100mA
• Current - Limit (min): 100mA
• Operating Temperature: -25°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Current, Output: 100 mA
• Package Type: SOIC-8
• Regulation, Line: 0.01 %/V
• Regulation, Load: 0.1 %
• Regulator Type: Positive Voltage Out
• Temperature, Operating, Range: -40 to +125 °C
• Voltage, Input: 40 V
• Voltage, Noise: 0.003 %
• Voltage, Output: 1.2 to 37 V
• Voltage, Supply, Rejection Ratio: 80 dB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Dropout (typical): -
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device
• Other names: *LM317LM; LM317LM

chip die out. Note that the load regulation error of about 14mV
(0.14%) is additional to the thermal regulation error.
PROTECTION DIODES
When external capacitors are used with any IC regulator it is
sometimes necessary to add protection diodes to prevent the
capacitors from discharging through low current points into
the regulator. Most 10μF capacitors have low enough internal
series resistance to deliver 20A spikes when shorted. Al-
though the surge is short, there is enough energy to damage
parts of the IC.
When an output capacitor is connected to a regulator and the
input is shorted, the output capacitor will discharge into the
output of the regulator. The discharge current depends on the
value of the capacitor, the output voltage of the regulator, and
D1 protects against C1
D2 protects against C2
LM317L micro SMD Light Sensitivity
Exposing the LM317L micro SMD package to bright sunlight
may cause the V
of fluorescent lighting the output is not affected. The LM317
REF
to drop. In a normal office environment
FIGURE 3. Regulator with Protection Diodes
7
the rate of decrease of V
is through a large junction that is able to sustain a 2A surge
with no problem. This is not true of other types of positive
regulators. For output capacitors of 25 μF or less, the
LM317L's ballast resistors and output structure limit the peak
current to a low enough level so that there is no need to use
a protection diode.
The bypass capacitor on the adjustment terminal can dis-
charge through a low current junction. Discharge occurs when
either the input or output is shorted. Internal to the LM317L is
a 50Ω resistor which limits the peak discharge current. No
protection is needed for output voltages of 25V or less and
10μF capacitance.
diodes included for use with outputs greater than 25V and
high values of output capacitance.
micro SMD does not sustain permanent damage from light
exposure. Removing the light source will cause LM317L's
V
REF
to recover to the proper value.
Figure 3
906409
IN
. In the LM317L, this discharge path
shows an LM317L with protection
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