MAX639：5V/3.3V/3V/可调、高效率、低IQ、降压型DC-DC转换器

在较宽负载范围内具有低电源电流、高转换效率

The MAX639/MAX640/MAX653 step-down switching regulators provide high efficiency over a wide range of load currents, delivering up to 225mA. A current-limiting pulse-frequency-modulated (PFM) control scheme gives the devices the benefits of pulse-width-modulated (PWM) converters (high efficiency at heavy loads), while using only 10µA of supply current (vs. 2mA to 10mA for PWM converters). The result is high efficiency over a wide range of loads. The MAX639/MAX640/MAX653 input range is 4V to 11.5V, and the devices provide lower preset output voltages of 5V, 3.3V, and 3V, respectively. Or, the output can be user-adjusted to any voltage from 1.3V to the input voltage. The MAX639/MAX640/MAX653 have an internal 1A power MOSFET switch, making them ideal for minimum-component, low- and medium-power applications. For increased output drive capability, use the MAX649/MAX651/MAX652 step-down controllers, which drive an external P-channel FET to deliver up to 5W.

关键特性

High Efficiency for a Wide Range of Load Currents
10µA Quiescent Current
Output Currents Up to 225mA
Preset or Adjustable Output Voltage:
- 5.0V (MAX639)
- 3.3V (MAX640)
- 3.0V (MAX653)
Low-Battery Detection Comparator
Current-Limiting PFM Control Scheme

MAX639、MAX640、MAX653：典型工作电路

应用

5V至3.3V转换
9V电池至5V、3.3V或3V转换
替代高效线性稳压器
便携式仪表与手持终端

数据手册DataSheet

语言	下载文件	备注
英文	MAX639-MAX653.pdf	Rev 4; 09/2005

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	Power Good Signal	DC-DC Outputs	Package/Pins	Budgetary Price
Part Number	min	max	min	max	Preset V_OUT (V)	Output Adjust. Method	max	Switch Type	Power Good Signal	DC-DC Outputs	Package/Pins	See Notes
MAX639	4	11.5	1.3	11.5	3 3.3 5	Preset Resistor	0.225	Internal	Yes	1	CDIP(N)/8 PDIP(N)/8 SOIC(N)/8	$3.38 @1k
MAX640					3.3						CDIP(N)/8 PDIP(N)/8 SOIC(N)/8	$3.38 @1k
MAX653					3						CDIP(N)/8 PDIP(N)/8 SOIC(N)/8	$1.55 @1k

技术资料

Solar Cells and Switching Regular Charge Batteries at Optimum Rates

订购型号

型号	状况	推荐替代产品	封装	温度	RoHS/无铅
MAX639C/D	生产中		DICE SALES,；NA引脚；DICE S；	0°C至+70°C	参考数据资料
MAX639CPA	停止供货	MAX639CPA+	PDIP(N),；8引脚；79.7mm²	0°C至+70°C	RoHS/无铅：否
MAX639CPA+	生产中		PDIP(N),；8引脚；79.7mm²	0°C至+70°C	RoHS/无铅：无铅
MAX639CSA	停止供货	MAX639CSA+	SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：否
MAX639CSA+	生产中		SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：无铅
MAX639CSA+T	生产中		SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：无铅
MAX639CSA-T	停止供货	MAX639CSA+T	SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：否
MAX639EPA	停止供货	MAX639EPA+	PDIP(N),；8引脚；79.7mm²	-40°C至+85°C	RoHS/无铅：否
MAX639EPA+	生产中		PDIP(N),；8引脚；79.7mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX639ESA	停止供货	MAX639ESA+	SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：否
型号	状况	推荐替代产品	封装：类型引脚占位面积封装图编码/变更 *	温度	RoHS/无铅？
MAX639ESA+	生产中		SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX639ESA+T	生产中		SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX639ESA-T	停止供货	MAX639ESA+T	SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：否
MAX639MJA	停止供货		CDIP(N),；8引脚；82.6mm²	-55°C至+125°C	RoHS/无铅：否

MAX639-MAX653.pdf MAX653

Solar Cells and Switching Regular Charge Batteries at Optimum Rates MAX639