- 您現在的位置：買賣IC網 > PDF目錄98282 > TPS53851RHHT (TEXAS INSTRUMENTS INC) SWITCHING CONTROLLER, PQCC36 PDF資料下載
參數資料
| 型號： | TPS53851RHHT |
| 廠商： | TEXAS INSTRUMENTS INC |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, PQCC36 |
| 封裝： | PLASTIC, VQFN-36 |
| 文件頁數： | 19/66頁 |
| 文件大小： | 1264K |
| 代理商： | TPS53851RHHT |
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頁第17頁第18頁當前第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頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁
I
RIPPLE +
V
IN * VOUT
L
V
OUT
V
IN
1
f
SW
I
PEAK +
I
RIPPLE
2
) IOC
SLUS985 – DECEMBER 2009
www.ti.com
In Figure 5-9, normal operation is occurring between t0 and t1 as shown by VOUT being at the regulated
voltage, (C) and normal switching on the SW NODE (B) and COMP at it's nominal level, (D). At t1, an
overcurrent load is experienced. The increased current forces COMP to increase to the ILIM level as
shown in (D). If the COMP voltage is above the ILIM voltage for 7 switching cycles, the controller enters a
hiccup mode. During this time the controller is not switching and the switching MOSFETs are turned off.
The TRCKn voltage goes through 7 cycles of charging and discharging the soft-start capacitor. At the end
of the 7 cycles the controller attempts another normal re-start. If the fault has been cleared, the output
voltage comes up to the regulation level as shown at time t3. If the fault has not cleared, the COMP
voltage again rises above the ILIM voltage and the hiccup mode repeats.
If the overcurrent condition exists for seven (7) PWM clock cycles the converter turns off the upper and
lower MOSFETs and initiates a hiccup mode restart. In hiccup mode, the TRKx pin is periodically charged
and discharged. After seven hiccup cycles, the controller attempts another soft-start cycle to restore
normal operation. If the overload condition persists, the controller returns to the hiccup mode. This
condition may continue indefinitely.
5.26 CALCULATING OVERCURRENT PROTECTION LEVEL
In order to set the desired overcurrent (IOC), a few variables must be known. The input and output voltage,
the output inductor value and it's DC resistance (DCR), as well as the switching frequency. Also known
are the ramp voltage which is 0.5 V and the VSHARE voltage, VSH which is 1.8 V. See the list of variables
and their values at the end of this section.
The overcurrent set point is in terms of the DC output current, but the current sense circuit monitors the
peak of the current. Therefore, the current ripple is needed and is calculated from
input voltage (VIN)
output voltage (VOUT)
switching frequency (fSW)
output inductance (L)
The ripple current is given by Equation 10.
(10)
The peak current detected is given by Equation 11, and used in Equation 13.
(11)
It is this IPEAK current that is detected by the current sense circuit. The two resistors needed to set the
peak overcurrent protection threshold and their connection for each channel is shown in Figure 5-10.
DESIGN HINT
Resistor R2 may be connected to the output voltage, VOUT, or to the output of the
differential amplifier, DIFFO, if used.
26
APPLICATION INFORMATION
Copyright 2009, Texas Instruments Incorporated
Product Folder Link(s): TPS53851
相關PDF資料 |
PDF描述 |
|---|---|
| TPS54010PWPG4 | 25 A SWITCHING REGULATOR, 762 kHz SWITCHING FREQ-MAX, PDSO28 |
| TPS54040DGQ | 0.5 A SWITCHING REGULATOR, 2500 kHz SWITCHING FREQ-MAX, PDSO10 |
| TPS54073PWPRG4 | 25 A SWITCHING REGULATOR, 762 kHz SWITCHING FREQ-MAX, PDSO28 |
| TPS54073PWPR | 25 A SWITCHING REGULATOR, 762 kHz SWITCHING FREQ-MAX, PDSO28 |
| TPS54073PWP | 25 A SWITCHING REGULATOR, 762 kHz SWITCHING FREQ-MAX, PDSO28 |
相關代理商/技術參數 |
參數描述 |
|---|---|
| TPS53915EVM-587 | 功能描述:TPS53915 SWIFT?, D-CAP3?, Eco-Mode? DC/DC, Step Down 1, Non-Isolated Outputs Evaluation Board 制造商:texas instruments 系列:SWIFT?，D-CAP3?，Eco-Mode? 零件狀態(tài):有效 主要用途:DC/DC，步降 輸出和類型:1，非隔離 功率 - 輸出:- 電壓 - 輸出:1.2V 電流 - 輸出:12A 電壓 - 輸入:12V 穩(wěn)壓器拓撲:降壓 頻率 - 開關:- 板類型:完全填充 所含物品:板 使用的 IC/零件:TPS53915 標準包裝:1 |
| TPS53915RVET | 制造商:Texas Instruments 功能描述:1.5V TO 18V INPUT (4.5V TO 25V BIAS), 12-A SYNCHRONOUS STEP- - Tape and Reel 制造商:Texas Instruments 功能描述:IC REG BUCK SYNC ADJ 12A 28VQFN |
| TPS5401 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:0.5-A, 42-V Input, Step-Down SWIFT? Converter |
| TPS54010 | 制造商:TI 制造商全稱:Texas Instruments 功能描述:SWIFT Converter Product Portfolio |
| TPS54010EVM-067 | 功能描述:電源管理IC開發(fā)工具 4.0 Vin DC/DC Conv RoHS:否 制造商:Maxim Integrated 產品: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。