CXSU6338B是一个升压转换器，提供来自低压电源的升压输出电压。
由于它的专利设计，它在一个很低的输入电压下启动到850mV，使它
单电池碱性/镍氢电池操作的理想选择。1MHz的开关频率允许使用微小的、
低剖面的电感和陶瓷电容器。电流模式的PWM设计是内部补偿的，减少了
外部零件计数。
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[ CXSU6338B ]
目录
1.产品概述 2.产品特点 3.应用范围 4.技术规格书下载（产品PDF文档）
5.产品封装图 6.电路原理图 7.功能概述 8.相关产品
一,产品概述(General Description) 
The CXSU6338B is a step-up converter that provides a boosted output voltage from a low voltage source.
Because of its proprietary design, it starts up at a very low input voltage down to 850mV, making it
an ideal choice for single cell alkaline/NiMH battery operations.
A switching frequency of 1MHz minimizes solution footprint by allowing the use of tiny, low profile
inductors and ceramic capacitors. The current mode PWM design is internally compensated, reducing
external parts count.
CXSU6338B is housed in a tiny SOT23-5 and SOT89-3 Package.
二.产品特点(Features)
Up to 95% Efficiency
Output voltage accuracy 3％
1MHz Switching Frequency allows small inductor
and output cap
Input boost-strapping allows using small or no
input cap
Low Vin Start-up Voltage down to 850mV Ideal
for Single Alkaline Cell operations
Maximum Output Current up to 300mA
Low Noise PWM control
Internally Compensated Current Mode Control
Internal Synchronous Rectifier
Logic Control Shutdown (IQ<1uA)
三,应用范围 (Applications)
One to Three Cell Battery Operated Devices
Medical Instruments
Bluetooth Headsets
Flash-Based MP3 Players
Noise Canceling Headphones
四.技术规格书下载（产品PDF）
需要详细的PDF规格书请扫一扫微信联系我们，还可以获得免费样品以及技术支持！
五,产品封装图 (Package)
六.电路原理图
七,功能概述
|
Parameters |
Condition |
Min. |
Typ. |
Max. |
Unit |
|
Minimum Input Voltage |
0.7 |
V |
|||
|
Startup Voltage |
0.85 |
1.1 |
V |
||
|
Dropout Voltage, Vout≥2.8V |
FB=OUT |
3.3 |
V |
||
|
FB=G |
5 |
V |
|||
|
FB Feedback Voltage |
Vout=2.5 to 5V |
0.6 |
V |
||
|
FB Input Current |
50 |
nA |
|||
|
Output Voltage Range |
External divider |
2.5 |
5 |
V |
|
|
Quiescent Current at OUT |
Vfb=0.7V |
25 |
uA |
||
|
Shutdown Supply Current at OUT |
EN=G |
0.1 |
1 |
uA |
|
|
NMOS Switch On Resistance |
Isw=100mA |
0.3 |
ohm |
||
|
PMOS Switch On Resistance |
Isw=100mA |
0.7 |
ohm |
||
|
NMOS Switch Current Limit |
1 |
A |
|||
|
SW Leakage Current |
Vout=5.5V, Vsw=0 or 5.5V, EN=G |
1 |
uA |
||
|
EN Input Current |
1 |
uA |
|||
|
EN Input Voltage for “Low” |
0.3 |
V |
|||
|
EN Input Voltage for “High” |
0.6 |
V |
八,相关芯片选择指南
| 升压型DC/DC转换器(DC/DC Step-up Converter ) | ||||||||||
| Part No. | MODE | VIN | VOUT | IQ | FOSC | Eff. | Accu. | Power switching | IOUT | Package |
| CXSU6337 | PFM | 0.8~5.5V | 2.5~6V 100mV Step | 4μA | 450KHz | 85% | ±2% | Internal MOSFET | 300mA | SOT89-3 SOT23-3 SOT23-5 |
| CXSU6337C | PFM | 0.8~5.5V | 2.5~6V 100mV Step | 6μA | 400KHz | 90% | ±2% | External MOSFET | - | SOT89-5 SOT23-3 SOT23-5 |
| CXSU6338B | Sync Boost PFM/PWM | 0.85~5V | 3.3, 5V, ADJ | 25μA | 1MHz | 95% | ±2% | Internal Sync Rectifier | 300mA | SOT23-5 |
| CXSU6339 | Sync Boost PWM | 0.9~5V | 1.8~3.6V | 8μA | 1MHz | 94% | ±2% | Internal Sync Rectifier | 300mA | SOT89-3 SOT23-3 SOT23-5 |
| CXSU6340 | Sync Boost PWM | 0.9~5V | 1.8~3.6V | 8μA | 1MHz | 94% | ±2% | Internal Sync Rectifier | 300mA | SOT89-3 SOT23-3 SOT23-5 |
