參數(shù)資料
型號: TPS54320RHLR
廠商: TEXAS INSTRUMENTS INC
元件分類: 穩(wěn)壓器
英文描述: SWITCHING REGULATOR, 1320 kHz SWITCHING FREQ-MAX, PQCC14
封裝: 3.50 X 3.50 MM, GREEN, PLASTIC, QFN-14
文件頁數(shù): 9/39頁
文件大?。?/td> 1358K
代理商: TPS54320RHLR
Time = 2 msec / div
EN = 2 V / div
Vout1 = 1 V / div
Vout2 = 1 V / div
Time = 2 msec / div
EN = 2 V / div
Vout1 = 1 V / div
Vout2 = 1 V / div
www.ti.com
SLVS982A – AUGUST 2010 – REVISED SEPTEMBER 2010
Figure 28. Ratio-metric Startup with Vout2 Leading
Figure 29. Simultaneous Startup
Vout1
Output Overvoltage Protection (OVP)
The device incorporates an output overvoltage protection (OVP) circuit to minimize output voltage overshoot. For
example, when the power supply output is overloaded, the error amplifier compares the actual output voltage to
the internal reference voltage. If the VSENSE pin voltage is lower than the internal reference voltage for a
considerable time, the output of the error amplifier demands maximum output current. Once the condition is
removed, the regulator output rises and the error amplifier output transitions to the steady state voltage. In some
applications with small output capacitance, the power supply output voltage can respond faster than the error
amplifier. This leads to the possibility of an output overshoot. The OVP feature minimizes the overshoot by
comparing the VSENSE pin voltage to the OVP threshold. If the VSENSE pin voltage is greater than the OVP
threshold the high-side MOSFET is turned off preventing current from flowing to the output and minimizing output
overshoot. When the VSENSE voltage drops lower than the OVP threshold, the high-side MOSFET is allowed to
turn on at the next clock cycle.
Overcurrent Protection
The device is protected from overcurrent conditions by cycle-by-cycle current limiting on both the high-side
MOSFET and the low-side MOSFET.
High-side MOSFET overcurrent protection
High-side MOSFET overcurrent protection is achieved by an internal current comparator that monitors the current
in the high-side MOSFET on a cycle-by-cycle basis. If this current exceeds the current limit threshold, the
high-side MOSFET is turned off for the remainder of that switching cycle.
During normal operation, the device implements current mode control which uses the COMP pin voltage to
control the turn off of the high-side MOSFET and the turn on of the low-side MOSFET, on a cycle by cycle basis.
Each cycle, the switch current and the current reference generated by the COMP pin voltage are compared.
When the peak switch current intersects the current reference, the high-side switch is turned off.
Low-side MOSFET overcurrent protection
While the low-side MOSFET is turned on, its conduction current is monitored by the internal circuitry. During
normal operation, the low-side MOSFET sources current to the load. At the end of every clock cycle, the low-side
MOSFET sourcing current is compared to the internally set low-side sourcing current limit. If the low-side
sourcing current is exceeded, the high-side MOSFET is not turned on and the low-side MOSFET stays on for the
next cycle. The high-side MOSFET is turned on again when the low-side current is below the low-side sourcing
current limit at the start of a cycle.
The low-side MOSFET may also sink current from the load. If the low-side sinking current limit is exceeded, the
low-side MOSFET is turned off immediately for the rest of that clock cycle. In this scenario both MOSFETs are
off until the start of the next cycle.
Copyright 2010, Texas Instruments Incorporated
17
Product Folder Link(s) :TPS54320
相關PDF資料
PDF描述
TPS54320RHL SWITCHING REGULATOR, PQCC14
TPS54327DDAR 5.7 A SWITCHING REGULATOR, 700 kHz SWITCHING FREQ-MAX, PDSO8
TPS54328DDA 5.7 A SWITCHING REGULATOR, 700 kHz SWITCHING FREQ-MAX, PDSO8
TPS54328DDAR 5.7 A SWITCHING REGULATOR, 700 kHz SWITCHING FREQ-MAX, PDSO8
TPS54331DG4 2 A SWITCHING REGULATOR, 684 kHz SWITCHING FREQ-MAX, PDSO8
相關代理商/技術參數(shù)
參數(shù)描述
TPS54320RHLT 功能描述:直流/直流開關調(diào)節(jié)器 4.5-17V Inp3A Sync Step Down Cnvrtr RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關頻率: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: 安裝風格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
TPS54320RHLT 制造商:Texas Instruments 功能描述:IC SYNC STEP-DOWN CONTROLLER 1.2MHZ Q 制造商:Texas Instruments 功能描述:IC, SYNC STEP-DOWN CONTROLLER, 1.2MHZ, QFN-14
TPS54325 制造商:TI 制造商全稱:Texas Instruments 功能描述:4.5-V to 18-V, 3-A OUTPUT SYNCHRONOUS STEP DOWN SWITCHER WITH INTEGRATED FET (SWIFT?)
TPS54325_10 制造商:TI 制造商全稱:Texas Instruments 功能描述:4.5-V to 18-V, 3-A OUTPUT SYNCHRONOUS STEP DOWN SWITCHER WITH INTEGRATED FET (SWIFT?)
TPS54325EVM 功能描述:電源管理IC開發(fā)工具 5-17V Input 3A SWIFT CVTR Eval RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:Battery Management 工具用于評估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V