- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄98282 > TPS54320RHLR (TEXAS INSTRUMENTS INC) SWITCHING REGULATOR, 1320 kHz SWITCHING FREQ-MAX, PQCC14 PDF資料下載
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)： | 17/39頁 |
| 文件大小： | 1358K |
| 代理商： | TPS54320RHLR |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁當(dāng)前第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁
(
)
(
)
( )
Tss ms Iss
A
C7(nF)
Vref V
×
=
m
Vout
Vref
R8
R9
Vref
-
=
SLVS982A – AUGUST 2010 – REVISED SEPTEMBER 2010
www.ti.com
Slow Start Capacitor Selection
The slow start capacitor determines the minimum amount of time it takes for the output voltage to reach its
nominal programmed value during power up. This is useful if a load requires a controlled voltage slew rate. This
is also used if the output capacitance is large and requires a large amount of current to charge the capacitor to
the output voltage level. The large currents necessary to charge the capacitor may either make the TPS54320
reach the current limit or the excessive current draw from the input power supply may cause the input voltage rail
to sag. Limiting the output voltage slew rate solves both of these problems. The soft start capacitor value can be
calculated using Equation 29. The example circuit has the soft start time set to an arbitrary value of 3.5ms which
requires a 10nF capacitor. In the TPS54320, Iss is 2.3A and Vref is 0.8V.
(29)
Bootstrap Capacitor Selection
A 0.1F ceramic capacitor must be connected between the BOOT to PH pin for proper operation. It is
recommended to use a ceramic capacitor with X5R or better grade dielectric. The capacitor should have 10V or
higher voltage rating.
Under Voltage Lockout Set Point
The Under Voltage Lock Out (UVLO) can be adjusted using the external voltage divider network of R1 and R2.
R1 is connected between VIN and the EN pin of the TPS54320 and R2 is connected between EN and GND. The
UVLO has two thresholds, one for power up when the input voltage is rising and one for power down or
brownouts when the input voltage is falling. For the example design, the supply should turn on and start
switching once the input voltage increases above 6.806V (UVLO start or enable). After the regulator starts
switching, it should continue to do so until the input voltage falls below 4.824V (UVLO stop or disable).
Equation 2 and Equation 3 can be used to calculate the values for the upper and lower resistor values. For the
stop voltages specified, the nearest standard resistor value for R1 is 511 k
and for R2 is 100k.
Output Voltage Feedback Resistor Selection
The resistor divider network, R8 and R9, is used to set the output voltage. For this example design, 10 k
Ω was
selected for R9. Using Equation 30, R8 is calculated as 31.25k
Ω. The nearest standard 1% resistor is 31.6kΩ.
(30)
Minimum Output Voltage
Due to the internal design of the TPS54320, there is a minimum output voltage limit for any given input voltage.
The output voltage can never be lower than the internal voltage reference of 0.8V. Above 0.8V, the output
voltage may be limited by the minimum controllable on time. The minimum output voltage in this case is given by
VOUTmin = Ontimemin x Fsmax (VINmax + IOUTmin (RDS2min - RDS1min)) - IOUTmin (RL + RDS2min)
(31)
Where:
VOUTmin = minimum achievable output voltage
Ontimemin = minimum controllable on time (135 nsec maximum)
Fsmax = maximum switching frequency including tolerance
VINmax = maximum input voltage
IOUTmin = minimum load current
RDS1min = minimum high side MOSFET on resistance (57m
typical)
RDS2min = minimum low side MOSFET on resistance (50m
typical)
RL = series resistance of output inductor
24
Copyright 2010, Texas Instruments Incorporated
Product Folder Link(s) :TPS54320
相關(guān)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(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| TPS54320RHLT | 功能描述:直流/直流開關(guān)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(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 |
| 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 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。