LP5520 datasheet(35/46 Pages) TI1

35 / 46 page

0.5

1.0

1.5

2.0

2.5

TIME (Ps)

INDUCTOR TDK VLF 3010 ± 4.7 PH

SUPPLY VOLTAGE (V)

3.0

3.2

3.5

3.7

4.0

4.2

80 mA

40 mA

20 mA

80.0

82.0

84.0

86.0

88.0

90.0

ILOAD = 60 mA

LP5520

www.ti.com

SNVS440B – MAY 2007 – REVISED MARCH 2016

Product Folder Links: LP5520

Submit Documentation Feedback

8.2.1.2.1.5

Inductor: L1

A 4.7-µH shielded inductor is suggested for LP5520 boost converter. The inductor must have a higher saturation

current rating than the peak current it receives during circuit operation (0.5 A – 1 A depending on the output

current). Equivalent series resistance (ESR) less than 500-m

Ω is suggested for high efficiency. Open core

inductors cause flux linkage with circuit components and interfere with the normal operation of the circuit. This

must be avoided. For high efficiency, choose an inductor with a high-frequency core material such as ferrite to

reduce the core losses. To minimize radiated noise, use a toroid, pot core or shielded core inductor. The inductor

must be connected to the SW pin as close to the device as possible. Examples of suitable inductors are: TDK

VLF3010AT-4R7MR70 and Coilcraft LPS3010-472NL.

8.2.1.2.1.6

List Of Recommended External Components

SYMBOL

SYMBOL EXPLANATION

VALUE

UNIT

TYPE

CVDDA

C between VDDA and GND

100

Ceramic, X7R / X5R

CVDDD

C between VDDD and GND

100

Ceramic, X7R, X5R

CVLDO

C between VLDO and GND

µF

Ceramic, X7R / X5R

CVDDIO

C between VDDIO and GND

100

Ceramic, X7R / X5R

COUT

C between FB and GND

2 × 4.7

µF

Ceramic, X7R / X5R, tolerance ±10%, DC bias

effect approximately 30% at 20 V

CIN

C between battery voltage and GND

µF

Ceramic, X7R / X5R

L between SW and VBAT

4.7

µH

Shielded, low ESR, ISAT 0.5 A

Rectifying diode (Vƒ at maximum load)

0. 3 – 0.5

Schottky diode, reverse voltage 30 V, repetitive

peak current 0.5 A

CSW

Optional C in EMI filter

330

Ceramic, X7R / X5R, 50V

RSW

Optional R in EMI filter

3.9

Ω

±1%

CHF

Optional high frequency output C

33 - 100

Ceramic, X7R, X5R, 50V

LSW

Ferrite bead in SW pin

30 - 300

Ω

at 100 Mhz

LEDs

User Defined

8.2.1.3 Application Curves

Figure 33. Boost Converter Efficiency

Figure 34. Boost Typical Waveforms at 60-mA Load

LP5520 Datenblatt(PDF) 35 Page - Texas Instruments

LP5520 Datenblatt(HTML) 35 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46

Datenblatt Download

Link URL