OUT

IN

EN

6

2

3

4

BYPASS

1

10 nF

1 µF

1 µF

Input

Enable

GND

LP3995

Load

CIN

CBP

COUT

(C3)

(A1)

(B2)

(A3)

(C1)

LP3995

www.ti.com

SNVS179F – FEBRUARY 2003 – REVISED SEPTEMBER 2015

9 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.

9.1 Application Information

The LP3995 can provide 150-mA output current with 2.5-V to 6-V input. It is stable with a 1-

μF ceramic output

capacitor. An optional external bypass capacitor reduces the output noise without slowing down the load

transient response. Typical output noise is 25

μVRMS at frequencies from 10 Hz to 100 kHz. Typical power supply

rejection is 60 dB at 1 kHz.

9.2 Typical Application

Figure 18. LP3995 Typical Application

9.2.1 Design Requirements

For typical CMOS voltage regulator applications, use the parameters listed in Table 1.

Table 1. Design Parameters

DESIGN PARAMETER

EXAMPLE VALUE

Minimum input voltage

2.5 V

Minimum output voltage

1.8 V

Output current

150 mA

9.2.2 Detailed Design Procedure

9.2.2.1 External Capacitors

In common with most regulators, the LP3995 requires external capacitors to ensure stable operation. The

LP3995 is specifically designed for portable applications requiring minimum board space and smallest

components. These capacitors must be correctly selected for good performance.

9.2.2.2 Input Capacitor

An input capacitor is required for stability. It is recommended that a 1-µF capacitor be connected between the

LP3995 IN pin and ground (this capacitance value may be increased without limit).

This capacitor must be located a distance of not more than 1 cm from the IN pin and returned to a clean

analogue ground. Any good quality ceramic, tantalum, or film capacitor may be used at the input.

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