MAX1791：高效率、10引脚µMAX、降压型控制器，用于笔记本电脑

The MAX1762/MAX1791 PWM step-down controllers provide high efficiency, excellent transient response, and high DC output accuracy needed for stepping down, high-voltage batteries to generate low-voltage CPU core, I/O, and chipset RAM supplies in notebook computers and PDAs. Maxim's proprietary Quick-PWM™ pulse-width modulator is a free-running constant on-time type with input feed-forward. Its high operating frequency (300kHz) allows small external components to be utilized in PC board area-critical applications such as subnotebook computers and smart phones. PWM operation occurs at heavy loads, and automatic switchover to pulse-skipping operation occurs at lighter loads. The external high-side p-channel and low-side n-channel MOSFETs require no bootstrap components. The MAX1762/MAX1791 are simple, easy to compensate, and do not have the noise sensitivity of conventional fixed-frequency current-mode PWMs. These devices achieve high efficiency at a reduced cost by eliminating the current-sense resistor found in traditional current-mode PWMs. Efficiency is further enhanced by their ability to drive synchronous-rectifier MOSFETs. The MAX1762/MAX1791 come in a 10-pin µMAX® package and offer two fixed voltages (Dual Mode™) for each device, 1.8V/2.5V/adj (MAX1762) and 3.3V/5.0V/adj (MAX1791).

关键特性

High Operating Frequency (300kHz)
No Current-Sense Resistor
Accurate Current Limit
±1% Total DC Error over Line and During Continuous Conduction
Dual Mode Fixed Output
- 1.8V/2.5V/adj (MAX1762)
- 3.3V/5.0V/adj (MAX1791)
0.5V to 5.5V Output Adjust Range
5V to 20V Input Range
Automatic Light-Load Pulse Skipping Operation
Free-Running On-Demand PWM
Foldback Mode™ UVLO
PFET/NFET Synchronous Buck
4.65V at 25mA Linear Regulator Output
5µA Shutdown Supply Current
230µA Quiescent Supply Current
10-Pin µMAX Package

MAX1762、MAX1791：典型工作电路

应用

双向寻呼器
模拟蜂窝电话
数字蜂窝电话
数码相机
笔记本电脑

数据手册DataSheet

语言	下载文件	备注
英文	MAX1762-MAX1791.pdf	Rev 1; 05/2006

关键参数

Part Number	V_IN (V)	V_IN (V)	V_OUT1 (V)	V_OUT1 (V)	Preset V_OUT (V)	Output Adjust. Method	I_OUT1 (A)	Switch Type	Synchronous Switching	DC-DC Outputs	Oper. Freq. (kHz)	Package/Pins	Budgetary Price
Part Number	min	max	min	max	Preset V_OUT (V)	Output Adjust. Method	max	Switch Type	Synchronous Switching	DC-DC Outputs	Oper. Freq. (kHz)	Package/Pins	See Notes
MAX1762	5	20	0.5	5.5	1.8 2.5	Preset Resistor	2	External	Yes	1	300	µMAX/10	$2.18 @1k
MAX1791	5	20	0.5	5.5	3.3 5	Preset Resistor	2	External	Yes	1	300	µMAX/10	$3.04 @1k

开发工具

MAX1791EVKIT

订购型号

型号	状况	推荐替代产品	封装	温度	RoHS/无铅
MAX1791EUB	停止供货	MAX1791EUB+	µMAX,；10引脚；15.4mm²	-40°C至+85°C	RoHS/无铅：否
MAX1791EUB+	生产中		µMAX,；10引脚；15.4mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX1791EUB+T	生产中		µMAX,；10引脚；15.4mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX1791EUB-T	生产中		µMAX,；10引脚；15.4mm²	-40°C至+85°C	RoHS/无铅：否

MAX1762-MAX1791.pdf MAX1791

典型工作电路 MAX1791