GMT G5108RDU, G5108P8U Schematic [ru]

Global Mixed-mode Technology

Low-Noise Step-up DC-DC Converter

Features

 90% Efficiency
 Adjustable Output from V
 0.2Ω, 24V Power MOSFET
 Cycle-by-Cycle 2A Current Limit
 2.5V to 5.5V Input Range
 600kHz/1.2MHz Switching Frequency
 MSOP-8, TDFN3X3-8 Package

Applications

 LCD Displays
 Portable Applications
 Hand-Held Devices

to 20V

IN

G5108

General Description

The G5108 boost converter in corporate high-per­formance, current-mode, frequency selectable pulse
width modulation (PWM) circuitry with a built-in 0.2Ω
n-channel MOSFET to provide a highly efficient regu­lator.

High switching frequency allows easy filtering and
faster loop performance. An external compensation
pin provides the user flexibility in determining loop dy­namics, allowing the use of small, low ESR ceramic
output capacitors. The device can produce an output
voltage as high as 20V. User programmed soft-start
with an external capacitor determines the input current
ramp rate.

The G5108 is available in a space-saving MSOP-8
and TDFN3X3-8 package.

Ordering Information

ORDER

NUMBER

G5108P8U G5108 -40°C ~ +85°C MSOP-8

G5108RDU 5108 -40°C ~ +85°C TDFN3X3-8

Note: P8: MSOP-8 RD:TDFN3X3-8

U: Tape & Reel

MARKING

TEMP.

RANGE

PACKAGE

Pin Configuration Typical Application Circuit

V

V

IN

IN

2.5V to 5.5V

COMP

COMP

SHDN

SHDN

GND

GND

2.5V to 5.5V

G5108

1

1

2

2

3

3

4

4

TDFN3X3-8

TDFN3X3-8

G5108

Thermal

Thermal

Pad

Pad

ON

1.2MHz

1.2MHz

=1.24 x (1+

=1.24 x (1+

OUT

OUT

ON

8

8

SS

SS

FSL

FSL

7

7

6

6

VCC

VCC

SW

SW

5

5

V

V

G5108

G5108

COMP

COMP

SS

1

1

FB

FB

2

2

3

3

4

4

MSOP-8

MSOP-8

SS

8

8

FB

FSL

FSL

7

7

VCC

VCC

6

6

SW

SW

5

5

FB

SHDN

SHDN

GND

GND

Note: Recommend connecting the Thermal Pad to

Note: Recommend connecting the Thermal Pad to

the Ground for excellent power dissipation.

the Ground for excellent power dissipation.

OFF

OFF

600kHz

600kHz

R1

R1

R2

R2

C1

C1
22µF

22µF

6

6

VCC

VCC

3

3

SHDN

SHDN

7

7

FSL

FSL

8

8

SS

SS

COMP

COMP

1

10nF

10nF

)

)

1

GND

GND

R

R

24k

24k

C

C

2.2nF

2.2nF

C

C

SW

SW

C

C

5

5

4

4

2

2

FB

FB

(Green)

L1

L1

4.7µH~10µH

4.7µH~10µH

22µF

22µF

R1

R1

R2

R2

V

V

OUT

OUT

8V

8V
200mA

C2

C2

200mA

Ver: 1.6

Nov 03, 2011

1

TEL: [phone]

http://www.gmt.com.tw