4

4

3

3

2

2

1

1

4

4

3

3

2

2

1

1

UNLESS NOTED:

RESISTORS: OHMS, 0402, 1%, 1/16W

CAPACITORS: uF, 0402, 10%, 50V

OPT

FREQ

EXT

1.5 MHz

NTC

INT

400mA

2.7 V - 11V

750 kHz

DISCONNECTED

CONNECTED

EMBEDDED INDUCTOR

1210

R12 TO BE CONNECTED TO " BAT "

NODE AT BAT TURRET (E6)

-B

ASSY

*

-A

1.40MEG

0 Ohm

OPEN

R10

R9

1.05MEG

LTC4120 - 4.2EUD

LTC4120EUD

U1

OFF

RUN

VIN > 11V

ON

2

DEMO CIRCUIT 1967A - A / B

1

2

400mA WIRELESS SYNCHRONOUS BUCK BATTERY CHARGER

N/A

LTC4120 - 4.2EUD / LTC4120EUD

NC

GEORGE B.

9 - 17 - 13

SIZE

DATE:

IC NO.

REV.

SHEET

OF

TITLE:

APPROVALS

PCB DES.

APP ENG.

TECHNOLOGY

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

CUSTOMER NOTICE

LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A

CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;

HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO

VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL

APPLICATION. COMPONENT SUBSTITUTION AND PRINTED

CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT

PERFORMANCE OR RELIABILITY. CONTACT LINEAR

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SCHEMATIC

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

SCALE = NONE

www.linear.com

GEORGE B.

PRODUCTION FAB

2

9 - 17- 13

-

REVISION HISTORY

DESCRIPTION

DATE

APPROVED

ECO

REV

VBAR

VPROG

INTVCC

INTVCC

D1

DFLS240L

E9

GND

C5

10µF

50V

E7

nCHRG

JP4

R6

0

C3

0.01µF

0603

L1

15.0uH

R4

2.0k

5%

C2S1

4700pF

5%

50V

0805

E6

BAT

C1

10uF

16V

0805

R10

*

U1

LTC4120-4.2EUD / LTC4120EUD

16

13

1

5

12

17

9

3

6

10

7

2

4

8

15

14

11

RUN

PROG

INTVCC

GND

NTC

GND

BAT

IN

DHC

BATSNS/FB

FREQ

BOOST

SW

CHGSNS

FAULT

CHRG

NC/FBG

E10

5V - 40V

VIN

E4

PROG

JP3

R9

*

E2

GND

E8

nFAULT

R5

3.01k

R2

412k

R11

100k

5%

D2

DFLS240L

E3

NTC

R1

1.40MEG

C2S2

0.022µF

5%

50V

0805

E5

GND

R7

10k

R12

100k

5%

C2

47uF

16V

1210

D3

DFLS240L

C4

2.2µF

6.3V

E1

Cx

C2P2

1800pF

5%

50V

0603

R3

10k

R8

0

JP2

C2P1

4700pF

5%

50V

0805

J1

DF3-3P-2DSA

1

2

3

BAT

GND

ENTC

Embedded

Inductor

43T

Lr

47µH

JP1

39V

D4

DFLZ39