MAX649：5V/3.3V/3V或可调、高效率、低IQ、降压型DC-DC控制器

在较宽负载范围内具有低电源电流、高转换效率

The MAX649/MAX651/MAX652 BiCMOS, step-down DC-DC switching controllers provide high efficiency over three decades of load current. A unique, current-limited pulse-frequency-modulated (PFM) control scheme gives these devices the benefits of pulse-width-modulation (PWM) converters (high efficiency at heavy loads), while using only 100µA of supply current (vs. 2mA to 10mA for PWM converters). The result is high efficiency over loads ranging from 10mA to more than 2.5A. These devices use miniature external components. Their high switching frequency (up to 300kHz) allows for less than 9mm diameter surface-mount inductors. The MAX649/MAX651/MAX652 have dropout voltages less than 1V and accept input voltages up to 16.5V. Output voltages are preset at 5V (MAX649), 3.3V (MAX651), and 3V (MAX652). These controllers can also be adjusted to any voltage from 1.5V to the input voltage by using two resistors. These step-down controllers drive external P-channel MOSFETs at loads greater than 10W. If less power is required, use the MAX639/MAX640/MAX653 step-down converters with on-chip FETs, which allow up to a 225mA load current.

关键特性

More than 90% Efficiency (10mA to 1.5A Loads)
More than 12.5W Output Power
100µA Max Quiescent Supply Current
5µA Max Shutdown Supply Current
Less than 1.0V Dropout Voltage
16.5V Max Input Voltage
5V (MAX649), 3.3V (MAX651), 3V (MAX652), or Adjustable Output Voltage
Current-Limited Control Scheme
Up to 300kHz Switching Frequency

MAX649、MAX651、MAX652：典型工作电路

应用

5V至3.3V绿色PC应用
电池供电应用
高效降压转换器
元件数最少的DC-DC转换器

数据手册DataSheet

语言	下载文件	备注
英文	MAX649-MAX652.pdf	Rev 3; 08/1997

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	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	DC-DC Outputs	Oper. Freq. (kHz)	Package/Pins	See Notes
MAX649	4	16.5	1.5	16.5	5	Preset Resistor	2.5	External	1	300	CDIP(N)/8 PDIP(N)/8 SOIC(N)/8	-
MAX651	4	16.5	1.5	16.5	3.3	Preset Resistor	2.5	External	1	300	CDIP(N)/8 PDIP(N)/8 SOIC(N)/8	$2.74 @1k

技术资料

Energy Management for Small Portable Systems

质量和环境数据

MAX649.pdf

订购型号

型号	状况	推荐替代产品	封装	温度	RoHS/无铅
MAX649CPA	停止供货		PDIP(N),；8引脚；79.7mm²	0°C至+70°C	RoHS/无铅：否
MAX649CSA	停止供货		SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：否
MAX649CSA+	停止供货		SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：无铅
MAX649CSA+T	停止供货		SOIC(N),；8引脚；30.9mm²	0°C至+70°C	RoHS/无铅：无铅
MAX649CSA-T	停止供货		N.SO；8引脚	0°C至+70°C	参考数据资料
MAX649EPA	停止供货		PDIP(N),；8引脚；79.7mm²	-40°C至+85°C	RoHS/无铅：否
MAX649EPA+	停止供货		PDIP(N),；8引脚；79.7mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX649ESA	停止供货	MAX649ESA+	SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：否
MAX649ESA+	生产中		SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：无铅
MAX649ESA+T	生产中		SOIC(N),；8引脚；30.9mm²	-40°C至+85°C	RoHS/无铅：无铅
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？
MAX649ESA-T	停止供货	MAX649ESA+T	N.SO；8引脚	-40°C至+85°C	参考数据资料
MAX649MJA	停止供货		CDIP(N),；8引脚；82.6mm²	-55°C至+125°C	RoHS/无铅：否

MAX649-MAX652.pdf MAX651

Energy Management for Small Portable Systems MAX604

MAX649.pdf MAX649