LT8642-1

1

Rev. 0

For more information www.analog.com

Document Feedback

TYPICAL APPLICATION

FEATURES

DESCRIPTION

18V, 10A Synchronous

Step-Down Silent Switcher

The LT®8642-1 synchronous step-down regulator fea-

tures Silent Switcher architecture designed to mini-

mize EMI emissions while delivering high efficiency at

high switching frequencies. This performance makes

the LT8642-1 ideal for noise sensitive applications

and environments.

The fast, clean, low-overshoot switching edges enable

high efficiency operation even at high switching frequen-

cies, leading to a small overall solution size. Peak current

mode control with a 20ns minimum on-time allows high

step-down ratios even at high switching frequencies.

transient response at high switching frequencies. The

enables synchronizing other regulators to the LT8642-1.

Burst Mode operation enables low standby current con-

sumption, forced continuous mode can control frequency

harmonics across the entire output load range, or spread

spectrum operation can further reduce EMI emissions.

Soft-start and tracking functionality is accessed via the

SS pin, and an accurate input voltage UVLO threshold

can be set using the EN/UV pin.

1.2V 10A Step-Down Converter

APPLICATIONS

n

n

Ultralow EMI Emissions

n

Optional Spread Spectrum Modulation

n

High Efficiency at High Frequency

n

n

n

Wide Input Voltage Range: 2.8V to 18V

n

10A Output Current

n

External Compensation: Fast Transient Response

and Current Sharing

n

n

n

n

Fast Minimum Switch On-Time: 20ns

n

Low Dropout Under All Conditions: 50mV at 1A

n

Forced Continuous Mode

n

Adjustable and Synchronizable: 200kHz to 3MHz

n

Output Soft-Start and Power Good

n

Small 20-Lead 3mm × 4mm LQFN Package

n

Server Power Applications

n

Automotive and Industrial Supplies

n

General Purpose Step-Down

All registered trademarks and trademarks are the property of their respective owners. Protected

by U.S. patent 8823345.

LT8642-1

SW

BST

GND

GND

EN/UV

RT

FB

GND

220µF

×2

1µF

100k

1.2V

10A

10µF

1µF

1µF

47nF

47pF

0.28µH

2.8V TO 18V

17.8k

150pF

11k

100k

EFFICIENCY

1MHz, L = 0.56µH

2MHz, L = 0.28µH

3MHz, L = 0.28µH

POWER LOSS

LOAD CURRENT (A)

1

2

3

4

5

6

7

8

9

10

60

65

70

75

80

85

90

95

100

0

0.4

0.8

1.2

1.6

2.0

2.4

2.8

3.2

86421 TA01b

INTERNAL CAPACITORS

PACKAGE

LT8642S

4mm × 4mm LQFN

LT8642-1

None

3mm × 4mm LQFN