LM137K/883 National Semiconductor, LM137K/883 Datasheet - Page 3

• Manufacturer Part Number: LM137K/883
• Description: Standard Regulator Neg -1.2V to -37V 1.5A 3-Pin (2+Tab) TO-3 Tray
• Manufacturer: National Semiconductor
• Type: Linearr

Specifications of LM137K/883

• Package: 3TO-3
• Function: Standard
• Number Of Outputs: 1
• Input Voltage Range: -40 to -4.2 V
• Output Voltage: -1.2 to -37 V
• Maximum Output Current: 1.5 A
• Output Type: Adjustable
• Operating Temperature: -55 to 150 °C
• Polarity: Negative
• Reference Voltage: -1.275 V

Electrical Characteristics
Note 4: Refer to RETS137H drawing for LM137H or RETS137K drawing for LM137K military specifications.
Schematic Diagram
Thermal Regulation
When power is dissipated in an IC, a temperature gradient
occurs across the IC chip affecting the individual IC circuit
components. With an IC regulator, this gradient can be es-
pecially severe since power dissipation is large. Thermal
regulation is the effect of these temperature gradients on
output voltage (in percentage output change) per Watt of
power change in a specified time. Thermal regulation error is
independent of electrical regulation or temperature coeffi-
cient, and occurs within 5 ms to 50 ms after a change in
power dissipation. Thermal regulation depends on IC layout
as well as electrical design. The thermal regulation of a
voltage regulator is defined as the percentage change of
V
applied. The LM137’s specification is 0.02%/W, max.
OUT
, per Watt, within the first 10 ms after a step of power is
(Note 1) (Continued)
3
LM137, V
V
I
Vertical sensitivity, 5 mV/div
IL
IN
= 0A → 0.25A → 0A
− V
OUT
OUT
= −40V
= −10V
FIGURE 1.
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