1

LT1930/LT1930A

APPLICATIO S

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

1A, 1.2MHz/2.2MHz,

Step-Up DC/DC Converters

in ThinSOT

s

1.2MHz Switching Frequency (LT1930)

s

2.2MHz Switching Frequency (LT1930A)

s

s

High Output Voltage: Up to 34V

s

5V at 480mA from 3.3V Input (LT1930)

s

12V at 250mA from 5V Input (LT1930A)

s

Wide Input Range: 2.6V to 16V

s

Uses Small Surface Mount Components

s

Low Shutdown Current: < 1

µA

s

Low Profile (1mm) ThinSOT

s

Pin-for-Pin Compatible with the LT1613

Figure 1. 5V to 12V, 300mA Step-Up DC/DC Converter

s

TFT-LCD Bias Supply

s

Digital Cameras

s

Cordless Phones

s

Battery Backup

s

Medical Diagnostic Equipment

s

Local 5V or 12V Supply

s

External Modems

s

PC Cards

s

xDSL Power Supply

Efficiency

The LT

power SOT-23 switching regulators. Both include an

internal 1A, 36V switch allowing high current outputs to be

generated in a small footprint. The LT1930 switches at

1.2MHz, allowing the use of tiny, low cost and low height

capacitors and inductors. The faster LT1930A switches at

2.2MHz, enabling further reductions in inductor size.

Complete regulator solutions approaching one tenth of a

square inch in area are achievable with these devices.

Multiple output power supplies can now use a separate

regulator for each output voltage, replacing cumbersome

quasi-regulated approaches using a single regulator and

custom transformers.

A constant frequency internally compensated current mode

PWM architecture results in low, predictable output noise

that is easy to filter. Low ESR ceramic capacitors can be

used at the output, further reducing noise to the millivolt

level. The high voltage switch on the LT1930/LT1930A is

rated at 36V, making the device ideal for boost converters

up to 34V as well as for single-ended primary inductance

converter (SEPIC) and flyback designs. The LT1930 can

generate 5V at up to 480mA from a 3.3V supply or 5V at

300mA from four alkaline cells in a SEPIC design.

The LT1930/LT1930A are available in the 5-lead ThinSOT

package.

GND

SW

SHDN

FB

5V

4

51

3

D1

L1

10

µH

2

R1

113k

LT1930

1930/A F01

C2

4.7

µF

C3*

10pF

C1

2.2

µF

R2

13.3k

12V

300mA

C1: TAIYO-YUDEN X5R LMK212BJ225MG

C2: TAIYO-YUDEN X5R EMK316BJ475ML

D1: ON SEMICONDUCTOR MBR0520

L1: SUMIDA CR43-100

*OPTIONAL

SHDN

LOAD CURRENT (mA)

0

70

75

80

400

1930 TA01

65

60

50

100

200

300

55

90

85

, LTC and LT are registered trademarks of Linear Technology Corporation

ThinSOT is a trademark of Linear Technology Corporation.