參數(shù)資料
型號(hào): TPS61221DCKR
廠商: TEXAS INSTRUMENTS INC
元件分類: 穩(wěn)壓器
英文描述: 0.4 A BATTERY CHARGE CONTROLLER, PDSO6
封裝: GREEN, PLASTIC, SC-70, 6 PIN
文件頁(yè)數(shù): 3/22頁(yè)
文件大?。?/td> 1333K
代理商: TPS61221DCKR
DETAILED DESCRIPTION
OPERATION
CONTROLLER CIRCUIT
I
L
t
200mA
(typ.)
ContinuousCurrentOperation
DiscontinuousCurrentOperation
200mA
(typ.)
Device Enable and Shutdown Mode
Startup
Operation at Output Overload
www.ti.com ............................................................................................................................................................................................... SLVS776 – JANUARY 2009
The TPS6122x is a high performance, high efficient family of switching boost converters. To achieve high
efficiency the power stage is realized as a synchronous boost topology. For the power switching two actively
controlled low RDSon power MOSFETs are implemented.
The device is controlled by a hysteretic current mode controller. This controller regulates the output voltage by
keeping the inductor ripple current constant in the range of 200 mA and adjusting the offset of this inductor
current depending on the output load. In case the required average input current is lower than the average
inductor current defined by this constant ripple the inductor current gets discontinuous to keep the efficiency high
at low load conditions.
Figure 23. Hysteretic Current Operation
The output voltage VOUT is monitored via the feedback network which is connected to the voltage error amplifier.
To regulate the output voltage, the voltage error amplifier compares this feedback voltage to the internal voltage
reference and adjusts the required offset of the inductor current accordingly. At fixed output voltage versions an
internal feedback network is used to program the output voltage, at adjustable versions an external resistor
divider needs to be connected.
The self oscillating hysteretic current mode architecture is inherently stable and allows fast response to load
variations. It also allows using inductors and capacitors over a wide value range.
The device is enabled when EN is set high and shut down when EN is low. During shutdown, the converter stops
switching and all internal control circuitry is turned off. In this case the input voltage is connected to the output
through the back-gate diode of the rectifying MOSFET. This means that there always will be voltage at the output
which can be as high as the input voltage or lower depending on the load.
After the EN pin is tied high, the device starts to operate. In case the input voltage is not high enough to supply
the control circuit properly a startup oscillator starts to operate the switches. During this phase the switching
frequency is controlled by the oscillator and the maximum switch current is limited. As soon as the device has
built up the output voltage to about 1.8V, high enough for supplying the control circuit, the device switches to its
normal hysteretic current mode operation. The startup time depends on input voltage and load current.
If in normal boost operation the inductor current reaches the internal switch current limit threshold the main
switch is turned off to stop further increase of the input current.
In this case the output voltage will decrease since the device can not provide sufficient power to maintain the set
output voltage.
If the output voltage drops below the input voltage the backgate diode of the rectifying switch gets forward biased
and current starts flow through it. This diode cannot be turned off, so the current finally is only limited by the
remaining DC resistances. As soon as the overload condition is removed, the converter resumes providing the
set output voltage.
Copyright 2009, Texas Instruments Incorporated
11
Product Folder Link(s): TPS61220 TPS61221 TPS61222
相關(guān)PDF資料
PDF描述
TPS61251DSGT SWITCHING REGULATOR, 3500 kHz SWITCHING FREQ-MAX, PDSO8
TPS61251DSG SWITCHING REGULATOR, 3500 kHz SWITCHING FREQ-MAX, PDSO8
TPS62000YEGR 1.6 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, BGA12
TPS62000YEGT 1.6 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, BGA12
TPS62000YEG 1.6 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, BGA12
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TPS61221DCKT 功能描述:直流/直流開關(guān)調(diào)節(jié)器 Tiny Low Inp Vltg Boost Cnvrtr RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
TPS61222DCKR 功能描述:直流/直流開關(guān)調(diào)節(jié)器 Tiny Low Inp Vltg Boost Cnvrtr RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
TPS61222DCKT 功能描述:直流/直流開關(guān)調(diào)節(jié)器 Tiny Low Inp Vltg Boost Cnvrtr RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
TPS61222MDCKTEP 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 Boost Converter with 5.5?A Quiescnt Crrnt RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT
TPS61223DCKR 制造商:Texas Instruments 功能描述: