NB681
28V, 6A, Low Iq, High Current
Synchronous Buck Converter with 2-Bit VID
The Future of Analog IC Technology
DESCRIPTION
FEATURES
The NB681 is a fully integrated, high-frequency,
synchronous, rectified, step-down, switch-mode
converter with 2-bit VID, especially designed for
IMVP8 applications—VCCIO, PRIMCORE,
V1.0A, EDRAM, and EOPIO. It offers a very
compact solution to achieve a 6A continuous
output current and a 7.5A peak output current
over a wide input supply range.
Wide 4.5V to 28V Operating Input Range
VCCIO/PRIMCORE/EDRAM/EOPIO/V1.0A
Compatible for IMVP8
Output Adjustable by 2-Bit VID
Low-Power Mode
25µA Low Quiescent Current
6A Continous Output Current
7.5A Peak Output Current
Selectable Ultrasonic Mode
Adaptive COT for Fast Transient
DC Auto-Tune Loop
Stable with POSCAP and Ceramic
Capacitors
1% Reference Voltage
Internal Soft Start
Output Discharge
The NB681 operates at high efficiency over a
wide output current load range based on MPS
proprietary switching loss reduction technology
and internal low Ron power MOSFETs.
Adaptive constant-on-time (COT) control mode
provides fast transient response and eases loop
stabilization. The DC auto-tune loop provides
good load and line regulation.
OCL, OVP, UVP, and Thermal Shutdown,
Latch-Off Reset via EN or Power Cycle
QFN 2mm x 3mm Package
To avoid audible noise, NB681 provides low-
power mode for power loss saving during the
low-power state and ultrasonic mode.
APPLICATIONS
Full protection features include OC limit, OVP,
UVP, and thermal shutdown.
Laptop Computers
Tablet PCs
The converter requires a minimal number of
external components, and it is available in a QFN
2mm x 3 mm package.
Networking Systems
Servers
Personal Video Recorders
Flat Panel Televisions and Monitors
Distributed Power Systems
All MPS parts are lead-free, halogen-free, and adhere to the RoHS directive. For
MPS green status, please visit the MPS website under Quality Assurance.
“MPS” and “The Future of Analog IC Technology” are registered trademarks of
Monolithic Power Systems, Inc.
TYPICAL APPLICATION
NB681 Rev. 1.04
12/28/2017
www.MonolithicPower.com
MPS Proprietary Information. Patent Protected. Unauthorized Photocopy and Duplication Prohibited.
© 2017 MPS. All Rights Reserved.
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