- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄98284 > TPS62270DRVR (TEXAS INSTRUMENTS INC) 0.84 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO6 PDF資料下載
參數(shù)資料
| 型號(hào)： | TPS62270DRVR |
| 廠商： | TEXAS INSTRUMENTS INC |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 0.84 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO6 |
| 封裝： | 2 X 2 MM, 0.80 MM HEIGHT, GREEN, PLASTIC, SON-6 |
| 文件頁數(shù)： | 4/24頁 |
| 文件大?。?/td> | 882K |
| 代理商： | TPS62270DRVR |
DETAILED DESCRIPTION
OPERATION
Power Save Mode
SLVS799C – NOVEMBER 2007 – REVISED JANUARY 2009 ........................................................................................................................................... www.ti.com
The TPS62270 step down converter operates with typically 2.25 MHz fixed frequency pulse width modulation
(PWM) at moderate to heavy load currents. At light load currents the converter automatically enters Power Save
Mode and operates then in PFM mode.
During PWM operation the converter use a unique fast response voltage mode controller scheme with input
voltage feed-forward to achieve good line and load regulation allowing the use of small ceramic input and output
capacitors. At the beginning of each clock cycle initiated by the clock signal, the High Side MOSFET switch is
turned on. The current flows now from the input capacitor via the High Side MOSFET switch through the inductor
to the output capacitor and load. During this phase, the current ramps up until the PWM comparator trips and the
control logic will turn off the switch. The current limit comparator will also turn off the switch in case the current
limit of the High Side MOSFET switch is exceeded. After a dead time preventing shoot through current, the Low
Side MOSFET rectifier is turned on and the inductor current will ramp down. The current flows now from the
inductor to the output capacitor and to the load. It returns back to the inductor through the Low Side MOSFET
rectifier.
The next cycle will be initiated by the clock signal again turning off the Low Side MOSFET rectifier and turning on
the on the High Side MOSFET switch.
If the load current decreases, the converter will enter Power Save Mode operation automatically. During Power
Save Mode the converter skips switching and operates with reduced frequency in PFM mode with a minimum
quiescent current to maintain high efficiency.
The transition from PWM mode to PFM mode occurs once the inductor current in the Low Side MOSFET switch
becomes zero, which indicates discontinuous conduction mode.
During the Power Save Mode the output voltage is monitored with a PFM comparator. As the output voltage falls
below the PFM comparator threshold of VOUT +1%, the device starts a PFM current pulse. For this the High
Side MOSFET switch will turn on and the inductor current ramps up. After the On-time expires the switch will be
turned off and the Low Side MOSFET switch will be turned on until the inductor current becomes zero.
The converter effectively delivers a current to the output capacitor and the load. If the load is below the delivered
current the output voltage will rise. If the output voltage is equal or higher than the PFM comparator threshold,
the device stops switching and enters a sleep mode with typical 15
A current consumption.
In case the output voltage is still below the PFM comparator threshold, further PFM current pulses will be
generated until the PFM comparator threshold is reached. The converter starts switching again once the output
voltage drops below the PFM comparator threshold.
With a fast single threshold comparator, the output voltage ripple during PFM mode operation can be kept very
small. The PFM Pulse is timing controlled, which allows to modify the charge transferred to the output capacitor
by the value of the inductor. The resulting PFM output voltage ripple depends in first order on the size of the
output capacitor and the inductor value. Increasing output capacitor values and/or inductor values will minimize
the output ripple.
The PFM mode is left and PWM mode entered in case the output current can not longer be supported in PFM
mode.
12
Copyright 2007–2009, Texas Instruments Incorporated
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| TPS62273DRVR | 0.84 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO6 |
| TPS62291TDRVRQ1 | 1 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO6 |
| TPS62361BYZHT | 4.3 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, BGA16 |
| TPS62400QDRCQ1 | SWITCHING REGULATOR, PDSO10 |
| TPS62410DRCTG4 | 1.6 A DUAL SWITCHING CONTROLLER, 2500 kHz SWITCHING FREQ-MAX, PDSO10 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| TPS62270DRVRG4 | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 2.25MHz 400mA Step Down Converter 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 |
| TPS62270DRVT | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 2.25MHz 400mA Step- Down Converter 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 |
| TPS62270DRVTG4 | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 2.25MHz 400mA Step Down Converter 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 |
| TPS62270EVM-306 | 功能描述:電源管理IC開發(fā)工具 TPS62270EVM-306 Eval Mod RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:Battery Management 工具用于評(píng)估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V |
| TPS62272DRVR | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 2.25MHz 400mA Step- Down Converter 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 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。