FEATURES

n

LTC3899

60V Low I

Q

, Triple

Output, Buck/Buck/Boost

Synchronous Controller

DESCRIPTION

The

LTC

®

3899

is a high performance triple output (buck/

buck/boost) DC/DC switching regulator controller that

drives all N-channel synchronous power MOSFET stages.

The constant frequency current mode architecture allows

a phase-lockable frequency of up to 850kHz. The LTC3899

operates from a wide 4.5V to 60V input supply range.

When biased from the output of the boost converter or

another auxiliary supply, the LTC3899 can operate from

an input supply as low as 2.2V after start-up.

The gate drive for the LTC3899 can be programmed from

5V to 10V to allow the use of logic-level or standard-level

FETs and to maximize efficiency. Internal switches in the

top gate drivers eliminate the need for external bootstrap

diodes. The 29μA no-load quiescent current extends op-

erating run time in battery-powered systems. OPTI-LOOP

®

compensation allows the transient response to be optimized

over a wide range of output capacitance and ESR values.

L,

LT, LTC, LTM, Burst Mode, OPTI-LOOP, Linear Technology and the Linear logo are

registered trademarks of Linear Technology Corporation. All other trademarks are the property

of their respective owners. Protected by U.S. Patents including 5481178, 5705919, 5929620,

6144194, 6177787, 6580258.

n

Dual Buck Plus Single Boost Synchronous Controllers

Wide Bias Input Voltage Range: 4.5V to 60V

Outputs Remain in Regulation Through Cold Crank

Down to a 2.2V Input Supply Voltage

Buck and Boost Output Voltages Up to 60V

Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)

No External Bootstrap Diodes Required

Low Operating I

Q

: 29μA (One Channel On)

100% Duty Cycle for Boost Synchronous MOSFET

Phase-Lockable Frequency (75kHz to 850kHz)

Programmable Fixed Frequency (50kHz to 900kHz)

Very Low Dropout Operation: 99% Duty Cycle (Bucks)

Low Shutdown I

Q

: 3.6μA

Fixed or Adjustable Boost Output Voltage Saves I

Q

Small 38-Lead 5mm

×

7mm QFN and TSSOP Packages

APPLICATIONS

n

Automotive Always-On and Start-Stop Systems

Distributed DC Power Systems

Multioutput Buck-Boost Applications

TYPICAL APPLICATION

V

OUT3

REGULATED AT 10V

WHEN V

IN

< 10V

FOLLOWS V

IN

WHEN

V

IN

> 10V

33µF

High Efficiency Wide Input Range Dual 5V/8.5V Converter

95

RUN1, 2, 3 V

BIAS

TG1

V

FB3

0.1µF

TG3

BOOST3

SW3

BG3

LTC3899

BOOST1

SW1

BG1

SENSE1

+

SENSE1

–

V

FB1

Efficiency vs Output Current

V

IN

= 12V

V

OUT

= 5V

94 Burst Mode OPERATION

0.1µF

4.9µH

9m

V

IN

2.2V TO 60V

(START-UP

ABOVE 5V)

3m

33µF

1.2µH

EFFICIENCY (%)

V

OUT1

5V

5A

93

92

91

90

89

GATE DRIVE (DRV

CC

)

5V

6V

8V

10V

0.1

1

OUTPUT CURRENT(A)

10

3899 TA01b

SENSE3

–

SENSE3

+

DRV

CC

INTV

CC

357k

68.1k

220µF

4.7µF

0.1µF

TG2

ITH1,2,3 BOOST2

SW2

BG2

DRVSET

SENSE2

+

SENSE2

–

V

FB2

0.1µF

6.5µH

15m

V

OUT2

8.5V

3A

88

0.01

VPRG3

649k

68.1k

68µF

3899 TA01a

GND

3899fa

For more information

www.linear.com/LTC3899

1

LTC3899

ABSOLUTE MAXIMUM RATINGS

(Notes 1, 3)

Bias Input Supply Voltage (V

BIAS

) .............. –0.3V to 65V

Topside Driver Voltages

BOOST1, BOOST2, BOOST3 .................. –0.3V to 76V

Switch Voltage (SW1, SW2, SW3) ................ –5V to 70V

DRV

CC

, (BOOST1-SW1), (BOOST2-SW2),

(BOOST3-SW3) ...........................................–0.3V to 11V

BG1, BG2, BG3, TG1, TG2, TG3 .......................... (Note 8)

RUN1, RUN2, RUN3 Voltages..................... –0.3V to 65V

SENSE1

+

, SENSE2

+

, SENSE1

–

SENSE2

–

Voltages ..................................... –0.3V to 65V

SENSE3

+

, SENSE3

–

Voltages ..................... –0.3V to 65V

PLLIN/MODE, FREQ, DRVSET Voltages ....... –0.3V to 6V

EXTV

CC

Voltage ......................................... –0.3V to 14V

ITH1, ITH2, ITH3, V

FB1

, V

FB2

Voltages ......... –0.3V to 6V

V

FB3

Voltage............................................... –0.3V to 65V

VPRG3, Voltage ........................................... –0.3V to 6V

TRACK/SS1, TRACK/SS2, SS3 Voltages...... –0.3V to 6V

Operating Junction Temperature Range (Note 2)

LTC3899E, LTC3899I ......................... –40°C to 125°C

LTC3899H .......................................... –40°C to 150°C

LTC3899MP ....................................... –55°C to 150°C

Storage Temperature Range .................. –65°C to 150°C

PIN CONFIGURATION

TOP VIEW

SENSE1

–

SENSE1

+

ITH1

V

FB1

SENSE1

+

SENSE1

–

FREQ

PLLIN/MODE

SS3

SENSE3

+

SENSE3

–

1

2

3

4

5

6

7

8

9

39

GND

38 VPRG3

37 TRACK/SS1

36 TG1

35 SW1

34 BOOST1

33 BG1

32 SW3

31 TG3

30 BOOST3

29 BG3

28 V

BIAS

27 EXTV

CC

26 DRV

CC

25 BG2

24 BOOST2

23 SW2

22 TG2

21 TRACK/SS2

20 DRVSET

FREQ 1

PLLIN/MODE 2

SS3 3

SENSE3

+

–

TRACK/SS1

TOP VIEW

VPRG3

ITH1

V

FB1

38 37 36 35 34 33 32

31 SW1

30 BOOST1

29 BG1

28 SW3

27 TG3

39

GND

26 BOOST3

25 BG3

24 V

BIAS

23 EXTV

CC

22 DRV

CC

21 BG2

20 BOOST2

13 14 15 16 17 18 19

V

FB2

ITH2

DRVSET

TRACK/SS2

TG2

SENSE2

+

SW2

4

5

SENSE3

V

FB3

10

ITH3 11

INTV

CC

12

RUN1 13

RUN2 14

RUN3 15

SENSE2

–

16

SENSE2

+

17

V

FB2

18

ITH2 19

V

FB3

6

ITH3 7

INTV

CC

8

RUN1 9

RUN2 10

RUN3 11

SENSE2 12

–

FE PACKAGE

38-LEAD PLASTIC TSSOP

T

JMAX

= 150°C,

θ

JA

= 25°C/W

EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB

UHF PACKAGE

38-LEAD (5mm

×

7mm) PLASTIC QFN

T

JMAX

= 150°C,

θ

JA

= 34°C/W

EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB

TG1

2

3899fa

For more information

www.linear.com/LTC3899

LTC3899

ORDER INFORMATION

LEAD FREE FINISH

LTC3899EFE#PBF

LTC3899IFE#PBF

LTC3899HFE#PBF

LTC3899MPFE#PBF

LTC3899EUHF#PBF

LTC3899IUHF#PBF

LTC3899HUHF#PBF

LTC3899MPUHF#PBF

TAPE AND REEL

LTC3899EFE#TRPBF

LTC3899IFE#TRPBF

LTC3899HFE#TRPBF

LTC3899MPFE#TRPBF

LTC3899EUHF#TRPBF

LTC3899IUHF#TRPBF

LTC3899HUHF#TRPBF

LTC3899MPUHF#TRPBF

PART MARKING*

LTC3899FE

3899

PACKAGE DESCRIPTION

38-Lead Plastic TSSOP

38-Lead (5mm

×

7mm) Plastic QFN

38-Lead (5mm

×

7mm) Plastic QFN

38-Lead (5mm

×

7mm) Plastic QFN

38-Lead (5mm

×

7mm) Plastic QFN

TEMPERATURE RANGE

–40°C to 125°C

–40°C to 150°C

–55°C to 150°C

–40°C to 125°C

–40°C to 150°C

–55°C to 150°C

Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.

Consult LTC Marketing for information on nonstandard lead based finish parts.

For more information on lead free part marking, go to:

http://www.linear.com/leadfree/

For more information on tape and reel specifications, go to:

http://www.linear.com/tapeandreel/

The

l

denotes the specifications which apply over the specified operating

junction temperature range, otherwise specifications are at T

A

= 25°C. (Note 2) V

BIAS

= 12V, V

RUN1,2,3

= 5V, V

EXTVCC

= 0V, V

DRVSET

=

0V, VPRG3 = Float unless otherwise noted.

SYMBOL

V

BIAS

V

FB1,2

V

FB3

PARAMETER

Bias Input Supply Operating Voltage Range

Buck Regulated Feedback Voltage

(Note 4) ITH1,2 Voltage = 1.2V

0°C to 85°C

l

ELECTRICAL CHARACTERISTICS

CONDITIONS

MIN

4.5

0.792

0.788

1.182

9.78

11.74

TYP

MAX

60

UNITS

V

nA

µA

%/V

%

mmho

0.800

1.200

10.00

12.00

–2

±0.01

4

5

0.002

0.808

0.812

1.218

10.22

12.26

±50

±0.05

6

7

0.02

0.1

–0.1

Boost Regulated Feedback Voltage

(Note 4) ITH3 Voltage = 1.2V

VPRG3 = FLOAT

VPRG3 = 0V

VPRG3 = INTV

CC

(Note 4)

VPRG3 = FLOAT

VPRG3 = 0V

VPRG3 = INTV

CC

(Note 4) V

BIAS

= 4.5V to 60V

(Note 4) Measured in Servo Loop,

∆ITH

Voltage = 1.2V to 0.7V

(Note 4) Measured in Servo Loop,

∆ITH

Voltage = 1.2V to 2V

l

I

FB1,2

I

FB3

Buck Feedback Current

Boost Feedback Current

V

REFLNREG

V

LOADREG

Reference Voltage Line Regulation

Output Voltage Load Regulation

l

0.01

–0.01

2

g

m1,2,3

Transconductance Amplifier g

m

(Note 4) ITH1,2,3 = 1.2V, Sink/Source 5µA

3899fa

For more information

www.linear.com/LTC3899

3

LTC3899

The

l

denotes the specifications which apply over the specified operating

junction temperature range, otherwise specifications are at T

A

= 25°C. (Note 2) V

BIAS

= 12V, V

RUN1,2,3

= 5V, V

EXTVCC

= 0V, V

DRVSET

=

0V, VPRG3 = Float unless otherwise noted.

SYMBOL

I

Q

PARAMETER

Input DC Supply Current

Pulse-Skipping or Forced Continuous Mode

(One Channel On)

CONDITIONS

(Note 5), V

DRVSET

= 0V

RUN1 = 5V and RUN2,3 = 0V or

RUN2 = 5V and RUN1,3 = 0V or

RUN3 = 5V and RUN1,2 = 0V,

V

FB1,2

= 0.83V (No Load), V

FB3

= 1.25V

RUN1,2,3 = 5V, V

FB1,2

= 0.83V (No Load),

V

FB3

= 1.25V

RUN1 = 5V and RUN2,3 = 0V or

RUN2 = 5V and RUN1,3 = 0V

V

FB1,2

= 0.83V (No Load)

RUN3 = 5V and RUN1,2 = 0V, V

FB3

= 1.25V

RUN1 = 5V and RUN2 = 0V or

RUN2 = 5V and RUN1 = 0V, RUN3 = 5V,

V

FB1,2

= 0.83V (No Load), V

FB3

= 1.25V

RUN1,2,3 = 5V, V

FB1,2

= 0.83V (No Load),

V

FB3

= 1.25V

RUN1,2,3 = 0V

DRV

CC

Ramping Up

DRVSET = 0V or R

DRVSET

≤ 100kΩ

DRVSET = INTV

CC

DRV

CC

Ramping Down

DRVSET = 0V or R

DRVSET

≤ 100kΩ

DRVSET = INTV

CC

V

OVL1,2

I

SENSE1,2

+

I

SENSE3

+

I

SENSE1,2

–

I

SENSE3

–

DF

MAX(TG)

DF

MAX(BG)

I

TRACK/SS1,2

I

SS

V

RUN1,2,3

ON

V

SENSE(MAX)

V

SENSE(CM)

Gate Driver

TG1,2,3

BG1,2,3

Pull-Up On-Resistance

Pull-Down On-Resistance

Pull-Up On-Resistance

Pull-Down On-Resistance

V

DRVSET

= INTV

CC

V

DRVSET

= INTV

CC

2.2

1.0

2.2

1.0

Ω

3899fa

ELECTRICAL CHARACTERISTICS

MIN

TYP

1.6

0.8

3

MAX

UNITS

mA

Pulse-Skipping or Forced Continuous Mode

(All Channels On)

Sleep Mode (One Channel On, Buck)

mA

55

µA

l

29

Sleep Mode (One Channel On, Boost)

Sleep Mode (Buck and Boost Channel On)

29

34

50

55

µA

Sleep Mode (All Three Channels On)

Shutdown

UVLO

Undervoltage Lockout

39

3.6

l

60

10

4.2

7.8

4.0

7.0

13

±1

µA

V

%

µA

4.0

7.5

3.6

6.4

7

3.8

6.7

10

170

Buck Feedback Overvoltage Protection

SENSE

+

Pin Current

SENSE

+

Pin Current

SENSE

–

Pins Current

SENSE

–

Pin Current

Maximum Duty Factor for TG

Maximum Duty Factor for BG

Soft-Start Charge Current

RUN Pin On Threshold

Maximum Current Sense Threshold

SENSE3 Pins Common Mode Range

(BOOST Converter Input Supply Voltage)

Measured at V

FB1,2

Relative to Regulated V

FB1,2

Bucks (Channels 1 and 2)

Boost (Channel 3)

Bucks (Channels 1 and 2)

V

OUT1,2

< V

INTVCC

– 0.5V

V

OUT1,2

> V

INTVCC

+ 0.5V

Boost (Channel 3) V

SENSE

+, V

SENSE

– = 12V

Bucks (Channels 1,2) in Dropout, FREQ = 0V

Boost (Channel 3) in Overvoltage

Bucks (Channels 1,2) in Overvoltage

Boost (Channel 3)

V

TRACK/SS1,2

= 0V

V

SS3

= 0V

V

RUN1

, V

RUN2

, V

RUN3

Rising

V

FB1,2

= 0.7V, V

SENSE1,2

– = 3.3V,

V

FB3

= 1.1V, V

SENSE3

+ = 12V

l

700

97.5

99

100

96

8

1.22

65

2.2

10

1.275

75

l

±1

µA

%

12

1.33

85

60

µA

V

mV

V

RUN1,2,3

Hyst RUN Pin Hysteresis

75

4

For more information

www.linear.com/LTC3899

LTC3899

The

l

denotes the specifications which apply over the specified operating

junction temperature range, otherwise specifications are at T

A

= 25°C. (Note 2) V

BIAS

= 12V, V

RUN1,2,3

= 5V, V

EXTVCC

= 0V, V

DRVSET

=

0V, VPRG3 = Float unless otherwise noted.

SYMBOL

BDSW1,2,3

TG1,2,3 t

r

TG1,2,3 t

f

BG1,2,3 t

r

BG1,2,3 t

f

TG1,2/BG1,2

t

1D

BG1,2/TG1,2

t

1D

TG3/BG3 t

1D

BG3/TG3 t

1D

t

ON(MIN)1,2

t

ON(MIN)3

V

DRVCC(INT)

V

LDOREG(INT)

V

DRVCC(EXT)

V

LDOREG(EXT)

V

EXTVCC

V

LDOHYS

V

DRVCC(50kΩ)

V

DRVCC(70kΩ)

V

DRVCC(90kΩ)

f

25kΩ

f

65kΩ

f

105kΩ

f

LOW

f

HIGH

f

SYNC

PLLIN V

IH

PLLIN V

IL

I

BST3

PARAMETER

BOOST to DRV

CC

Switch On-Resistance

TG Transition Time:

Rise Time

Fall Time

BG Transition Time:

Rise Time

Fall Time

Top Gate Off to Bottom Gate On Delay

Synchronous Switch-On Delay Time

Bottom Gate Off to Top Gate On Delay

Top Switch-On Delay Time

CH3 Top Gate Off to Bottom Gate On Delay

Bottom Switch-On Delay Time

CH3 Bottom Gate Off to Top Gate On Delay

Synchronous Switch-On Delay Time

Buck Minimum On-Time

Boost Minimum On-Time

DRV

CC

Voltage from Internal V

BIAS

LDO

DRV

CC

Load Regulation from V

BIAS

LDO

DRV

CC

Voltage from Internal EXTV

CC

LDO

DRV

CC

Load Regulation from Internal

EXTV

CC

LDO

EXTV

CC

LDO Switchover Voltage

EXTV

CC

Hysteresis

Programmable DRV

CC

Programmable DRV

CC

Programmable DRV

CC

Programmable Frequency

Low Fixed Frequency

High Fixed Frequency

Synchronizable Frequency

PLLIN/MODE Input High Level

PLLIN/MODE Input Low Level

BOOST3 Charge Pump Available Output

Current

R

DRVSET

= 50kΩ, V

EXTVCC

= 0V

R

DRVSET

= 70kΩ, V

EXTVCC

= 0V

R

DRVSET

= 90kΩ, V

EXTVCC

= 0V

R

FREQ

=25kΩ, PLLIN/MODE = DC Voltage

R

FREQ

= 65kΩ, PLLIN/MODE = DC Voltage

R

FREQ

= 105kΩ, PLLIN/MODE = DC Voltage

V

FREQ

= 0V, PLLIN/MODE = DC Voltage

V

FREQ

= INTV

CC

, PLLIN/MODE = DC Voltage

PLLIN/MODE = External Clock

FREQ = 0V, PLLIN/MODE = INTV

CC

V

BOOST3

= 16.5V, V

SW3

= 12V

V

BOOST3

= 19V, V

SW3

= 12V

l

ELECTRICAL CHARACTERISTICS

CONDITIONS

V

SW

= 0V, V

DRVSET

= INTV

CC

(Note 6) V

DRVSET

= INTV

CC

C

LOAD

= 3300pF

C

LOAD

= 3300pF

(Note 6) V

DRVSET

= INTV

CC

C

LOAD

= 3300pF

C

LOAD

= 3300pF

C

LOAD

= 3300pF Each Driver, V

DRVSET

= INTV

CC

C

LOAD

= 3300pF Each Driver, V

DRVSET

= INTV

CC

C

LOAD

= 3300pF Each Driver, V

DRVSET

= INTV

CC

C

LOAD

= 3300pF Each Driver, V

DRVSET

= INTV

CC

(Note 7) V

DRVSET

= INTV

CC

(Note 7) V

DRVSET

= INTV

CC

V

EXTVCC

= 0V

7V < V

BIAS

< 60V, DRVSET = 0V

11V < V

BIAS

< 60V, DRVSET = INTV

CC

I

CC

= 0mA to 50mA, V

EXTVCC

= 0V

7V < V

EXTVCC

< 13V, DRVSET = 0V

11V < V

EXTVCC

< 13V, DRVSET = INTV

CC

I

CC

= 0mA to 50mA, V

EXTVCC

= 8.5V,

V

DRVSET

= 0V

EXTV

CC

Ramping Positive

DRVSET = 0V or R

DRVSET

≤ 100kΩ

DRVSET = INTV

CC

MIN

TYP

3.7

25

15

25

15

55

50

85

80

120

MAX

UNITS

Ω

ns

DRV

CC

Linear Regulator

5.8

9.6

5.8

9.6

6.0

10.0

0.9

6.0

10.0

0.7

6.2

10.4

2.0

6.2

10.4

2.0

V

%

V

%

4.5

7.4

4.7

7.7

250

5.0

4.9

8.0

V

mV

V

6.4

7.0

9.0

105

7.6

V

kHz

Oscillator and Phase-Locked Loop

375

320

485

75

2.5

440

835

350

535

380

585

850

0.5

505

kHz

V

BOOST3 Charge Pump

75

35

µA

3899fa

For more information

www.linear.com/LTC3899

5

参数名称	属性值
输出电压（最小值/固定）	2.2V
输出电压（最大值）	60V
开关工作频率	105kHz ~ 835kHz, 350kHz ~ 535kHz
输出类型	Transistor Driver
输出电压的路数	3
最小输入电压	4.5V
最大输入电压	60V
电源拓扑结构	Buck, Buck-Boost
同步整流与否	Yes
功能类型	Step-Down
输出配置	Positive

LTC3899EFE#PBF

LTC3899EFE#PBF概述

LTC3899EFE#PBF规格参数

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