固定1.2兆赫振荡器频率同步整流器CXSU63139低ESR输出电容稳定电流模式升压调节器92%效率

CXSU63139是同步整流器，固定开关频率（典型为1.2兆赫），以及电流模式升压调节器。该设备允许使用USB设备的小电感和输出电容器。电流模式控制方案具有快速的瞬态响应和良好的输出电压精度，在轻负载时，CXSU63139将自动进入脉冲频率调制（PFM）操作，以降低主开关损耗

目录

1.产品概述                       2.产品特点
3.应用范围                       4.下载产品资料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)         

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      The CXSU63139 is a synchronous rectifier, fixed switching frequency (1.2MHz typical), and
current-mode step-up regulator. The device allows use of small inductors and output capacitors for USB devices. The current-mode control scheme provides fast transient response and good output voltage accuracy.At light loads, the CXSU63139 will automatically enter in Pulse Frequency Modulation (PFM) operation to reduce the dominant switching losses. During PFM operation,the IC consumes very low quiescent current and maintains high efficiency over the complete load range.
      The CXSU63139 also includes current-limit and over-temperature shutdown to prevent damage
in the event of an output overload.
      The CXSU63139 is available in 4mmx4mm TQFN4x4-16 and DFN3x3-12 packages.
二.产品特点(Features)

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1.)92% Effiicency Synchronous Boost Converter With 1000-mA Output Current From
      1.8V Input
2.)Stable with Low ESR Output Capacitors
3.)Fixed 1.2MHz Oscillator Frequency
4.)Low EMI Converter (Integrated Anti-Ringing Function)
5.)Low Battery Output
6.)Integrated Power Save Mode Operation to Improve Light Load Efficiency
7.)Load Disconnected During Shutdown
8.)Output Current-Limit Protection
9.)Over Temperature Protection
10.)Under Voltage Protection
11.)Enable/Shutdown Function
12.)Available in TQFN4x4-16 and DFN3x3-12 Packages
13.)Lead Free and Green Devices Available (RoHS Compliant)
三,应用范围 (Applications)

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Power Bank
Tablet
Portable Equiment
四.下载产品资料PDF文档 

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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)

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PIN	NAME	FUNCTION
1,15,16	VOUT	Converter Output and IC Supply Voltage.
2	NC	Enable in Charge Done No Internal Connection.
3,4	SW	Converter Switch Pin. Connect inductor here.
5,6,7	PGND	Enable in Charge Done Power Ground. Connect these pins to GND.
8	VBAT	Converter Supply Voltage.                      Enable in Charge Done
9	LBI	Low Battery Indicator.
10	PSI	Power Saving Input. Force VPSI exceed 1V enter PFM. Left VPSI below 0.4V enter PWM mode.
11	EN	Device Enable Control Input. Force VEN exceed 1V enable the device. Left VEN below 0.4V to shutdown.
12	LBO	Low Battery Output.
13	GND	Signal Ground. Connect this pin to PGND.
14	FB	Converter Feedback Input.
Exposed Pad	PGND	Power Ground. Tie this pin to the ground island/plane through the lowest impedance connection available.

六.电路原理图

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七,功能概述

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Main Control Loop

The CXSU63139 is a constant frequency, synchronous rectifier, and current-mode switching regulator. 

In normal operation, the internal N-channel power MOSFET is turned on each cycle when the oscillator

 sets an internal RS latch and turned off when an internal comparator (ICMP) resets the latch. The peak

 inductor current which ICMP resets the RS latch is controlled by the voltage on the COMP node, which 

is the output of the error amplifier (EAMP). An external resistive divider connected between VOUT and 

ground allows the EAMP to receive an output feedback voltage VFB at FB pin. When the load current 

increases, it causes a slightly decrease in VFB relative to the 0.5V reference, which in turn causes the

 COMP volt- age to increase until the average inductor current matches the new load current.
 Start-up
A start-up oscillator circuit is integrated in the CXSU63139.When the device enables, the circuit pumps

 the output voltage high. Once the output voltage reaches 1.6V (typ),the main DC-DC circuitry turns on

 and boosts the output voltage to the final regulation voltage. 
Automatic PFM/PWM mode Switch
The CXSU63139 is a fixed frequency PWM peak current modulation control step-up converter. At light

 loads, theCXSU63139 will automatically enter in pulse frequency modulation operation to reduce the 

dominant switching losses. In PFM operation, the inductor current may reach zero or reverse on each

 pulse. A zero current comparator turns off the P-channel synchronous MOSFET, forcing DCM(Discontinuous

 Current Mode) operation at light load.These controls get very low quiescent current, help to maintain 

high efficiency over the complete load range. 
Synchronous Rectification
The internal synchronous rectifier eliminates the need for an external Schottky diode, thus reducing cost

 and board space. During the cycle off-time, the P-FET turns on and shunts the FET body diode. As a 

result, the syn-chronous rectifier significantly improves efficiency with-out the addition of an external

 component. Conversion efficiency can be as high as 92%.
Load Disconnect
Driving EN to ground places the CXSU63139 in shutdown mode. When in shutdown, the internal power

 MOSFET turns off, all internal circuitry shuts down and the quies-cent supply current reduces to 1μA

 maximum.A special circuit is applied to disconnect the load from the input during shutdown the 

converter. In conventional syn-chronous rectifier circuits, the back-gate diode of the high-side P-FET 

is forward biased in shutdown and allows current flowing from the battery to the output. However,this

 device uses a special circuit, which takes the cath-ode of the back-gate diode of the high-side P-FET

 and disconnects it from the source when the regulator is shutdown. The benefit of this feature for 

the system de-sign engineer is that the battery is not depleted during shutdown of the converter.  

No additional componentsmust be added to the design to make sure that the bat-tery is disconnected

 from the output of the converter. 
Current-Limit Protection
The CXSU63139 monitors the inductor current, flowing through the N-FET, and  limits the current 

peak at current-limit level to prevent loads and the CXSU63139 from dam-ages during overload

 conditions.
Over-Temperature Protection (OTP)
The over-temperature circuit limits the junction tempera-ture of the CXSU63139. When the junction

 temperature ex-ceeds 150oC, a thermal sensor turns off the both N-FETand P-FET, allowing the 

devices to cool. The thermal sensor allows the converters to start a soft-start process and regulate

 the output voltage again after the junction temperature cools by 30oC. The OTP is designed with 

a 30oC hysteresis to lower the average Junction Tempera-ture (TJ) during continuous thermal overload conditions,increasing the lifetime of the device.

八,相关产品                 更多同类产品......

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Switching Regulator > Boost Converter
Part_No	Package	Archi-tecture	Input  Voltage		Max Adj. Output  Voltage		Switch Current Limit (max)	Fixed  Output  Voltage	Switching  Frequency	Internal Power   Switch	Sync. Rectifier
			min	max	min	max	(A)	(V)	(kHz)
CXSU63133	SOT89	VM	0.9	5.5	2.5	5.5	0.5	1.8|2.6|2.8|3 |3.3|3.8|4.5|5	-	No	Yes
CXSU63134	MSOP8|TSSOP8 |SOP8	VM	2.5	5.5	2.5	-	-	-	200 ~ 1000	No	No
CXSU63135	TSSOP8|SOP-8P	VM	1	5.5	2.5	5	1	2.5|3.3	300	Yes	Yes
CXSU63136	SOP8	CM	3	40	1.25	40	1.5	-	33 ~ 100	Yes	No
CXSU63137	TQFN5x5-32	CM	2.5	6.5	2.5	18	3	No	1200	Yes	No
CXSU63138	TSOT23-5 TDFN2x2-6	CM	2.5	6	2.5	20	2	-	1500	Yes	No
CXSU63139	TQFN4x4-6 TDFN3x3-12	CM	1.8	5.5	2.7	5.5	5	-	1.2	Yes	Yes
CXSU63140	SOT23-5	CM	2.5	6	2.5	32	1	-	1000	Yes	No
CXSU63141	TSOT-23-6  TDFN2x2-8	CM	1.2	5.5	1.8	5.5	1.2	-	1.2	Yes	Yes