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LM137, LM337-N

SNVS778E – MAY 1999 – REVISED JANUARY 2016

www.ti.com

8 Application and Implementation

NOTE

Information in the following applications sections is not part of the TI component

specification, and TI does not warrant its accuracy or completeness. TI’s customers are

responsible for determining suitability of components for their purposes. Customers should

validate and test their design implementation to confirm system functionality.

8.1 Application Information

The LM137 and LM337-N are versatile, high performance, negative output linear regulators with high accuracy

and a wide temperature range. An output capacitor can be added to further improve transient response, and the

ADJ pin can be bypassed to achieve very high ripple-rejection ratios. The device's functionality can be utilized in

many different applications that require negative voltage supplies, such as bipolar amplifiers, operational

amplifiers, and constant current regulators.

8.2 Typical Applications

8.2.1 Adjustable Negative Voltage Regulator

The LM137 and LM337-N can be used as a simple, negative output regulator to enable a variety of output

voltages needed for demanding applications. By using an adjustable R2 resistor, a variety of negative output

voltages can be made possible as shown in Figure 16.

Full output current not available at high input-output voltages

†C1 = 1-

μF solid tantalum or 10-μF aluminum electrolytic required for stability

*C2 = 1-

μF solid tantalum is required only if regulator is more than 4 inches from power-supply filter capacitor

Output capacitors in the range of 1

μF to 1000 μF of aluminum or tantalum electrolytic are commonly used to provide

improved output impedance and rejection of transients

Figure 16. Adjustable Negative Voltage Regulator

(2)

8.2.1.1 Design Requirements

The device component count is very minimal, employing two resistors as part of a voltage divider circuit and an

output capacitor for load regulation. An input capacitor is needed if the device is more than 4 inches from the

filter capacitors.

8.2.1.2 Detailed Design Procedure

The output voltage is set based on the selection of the two resistors, R1 and R2, as shown in Figure 16.

12

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