LM2647

更新时间： 2024-11-06 00:01:07

品牌	Logo	应用领域
美国国家半导体 - NSC		稳压器控制器
页数	文件大小	规格书
26页	729K
描述
Dual Synchronous Buck Regulator Controller

阅读下载

中文翻译

获取价格

数据手册

如果您发现信息不准确，欢迎纠错

LM2647 数据手册

June 2003

LM2647

Dual Synchronous Buck Regulator Controller

General Description

Features

n Input voltage range from 5.5V to 28V

The LM2647 is an adjustable 200-500kHz dual channel

voltage-mode controlled high-speed synchronous buck

regulator controller ideally suited for battery powered appli-

cations such as laptop and notebook computers. The

LM2647 requires only N-channel FETs for both the upper

and lower positions of each synchronous stage. It features

line feedforward to improve the response to input transients.

At very light loads, the user can choose between the high-

efficiency Pulse-skip mode or the constant frequency

Forced-PWM mode. Lossless current limiting without the use

of external sense resistors is made possible by sensing the

voltage drop across the bottom FET. A unique adaptive duty

cycle clamping technique is incorporated to significantly re-

duce peak currents under abnormal load conditions. The two

independently programmable outputs switch 180˚ out of

phase (interleaved switching) to reduce the input capacitor

and filter requirements. The input voltage range is 5.5V to

28V while the output voltages are adjustable down to 0.6V.

n Synchronous dual-channel Interleaved switching

n Forced-PWM or Pulse-skip modes

n Lossless bottom-side FET current sensing

n Adaptive duty cycle clamping

n High current N-channel FET drivers

n Low shutdown supply currents

n Reference voltage accurate to within 1.5%

n Output voltage adjustable down to 0.6V

n Power Good flag and Chip Enable

n Under-voltage lockout

n Over-voltage/Under-voltage protection

n Soft-start and Soft-shutdown

n Switching frequency adjustable 200kHz-500kHz

Applications

n Notebook Chipset Power Supplies

n Low Output Voltage High-Efficiency Buck Regulators

Standard supervisory and control features include Soft-start,

Power Good, output Under-voltage and Over-voltage protec-

tion, Under-voltage Lockout, Soft-shutdown and Enable.

Typical Application (Channel 2 in parenthesis)

20056304

DS200563

www.national.com

12 3 4 5 6 7...26

中文翻译

下载PDF

与LM2647相关器件

型号	品牌	获取价格	描述	数据表
LM2647_15	TI	获取价格	LM2647 Dual Synchronous Buck Regulator Controller
LM2647LQ	NSC	获取价格	Dual Synchronous Buck Regulator Controller
LM2647LQ/NOPB	TI	获取价格	LM2647 Dual Synchronous Buck Regulator Controller
LM2647LQX	NSC	获取价格	Dual Synchronous Buck Regulator Controller
LM2647LQX/NOPB	TI	获取价格	Dual Synchronous Buck Regulator Controller 28-WQFN -5 to 125
LM2647MTC	NSC	获取价格	Dual Synchronous Buck Regulator Controller
LM2647MTC	TI	获取价格	DUAL SWITCHING CONTROLLER, 345kHz SWITCHING FREQ-MAX, PDSO28, TSSOP-28
LM2647MTC/NOPB	TI	获取价格	LM2647 Dual Synchronous Buck Regulator Controller
LM2647MTCX	NSC	获取价格	Dual Synchronous Buck Regulator Controller
LM2647MTCX	TI	获取价格	DUAL SWITCHING CONTROLLER, 345kHz SWITCHING FREQ-MAX, PDSO28, TSSOP-28