參數(shù)資料
型號: TPS2556DRB
廠商: TEXAS INSTRUMENTS INC
元件分類: 電源管理
英文描述: 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO8
封裝: PLASTIC, SON-8
文件頁數(shù): 2/22頁
文件大?。?/td> 942K
代理商: TPS2556DRB
SLVS931 – NOVEMBER 2009
www.ti.com
FAULT RESPONSE
The FAULT open-drain output is asserted (active low) during an overcurrent or overtemperature condition. The
TPS2556/57 asserts the FAULT signal until the fault condition is removed and the device resumes normal
operation. The TPS2556/57 is designed to eliminate false FAULTreporting by using an internal delay "deglitch"
circuit for overcurrent (9-ms typ) conditions without the need for external circuitry. This ensures that FAULTis not
accidentally asserted due to normal operation such as starting into a heavy capacitive load. The deglitch circuitry
delays entering and leaving current-limit induced fault conditions. The FAULTsignal is not deglitched when the
MOSFET is disabled due to an overtemperature condition but is deglitched after the device has cooled and
begins to turn on. This unidirectional deglitch prevents FAULT oscillation during an overtemperature event.
UNDERVOLTAGE LOCKOUT (UVLO)
The undervoltage lockout (UVLO) circuit disables the power switch until the input voltage reaches the UVLO
turn-on threshold. Built-in hysteresis prevents unwanted on/off cycling due to input voltage droop during turn on.
ENABLE (EN OR EN)
The logic enable controls the power switch and device supply current. The supply current is reduced to less than
2-
μA when a logic high is present on EN or when a logic low is present on EN. A logic low input on EN or a logic
high input on EN enables the driver, control circuits, and power switch. The enable input is compatible with both
TTL and CMOS logic levels.
THERMAL SENSE
The TPS2556/57 self protects by using two independent thermal sensing circuits that monitor the operating
temperature of the power switch and disable operation if the temperature exceeds recommended operating
conditions. The TPS2556/57 device operates in constant-current mode during an overcurrent conditions, which
increases the voltage drop across power switch. The power dissipation in the package is proportional to the
voltage drop across the power switch, which increases the junction temperature during an overcurrent condition.
The first thermal sensor (OTSD) turns off the power switch when the die temperature exceeds 135°C (min) and
the part is in current limit. Hysteresis is built into the thermal sensor, and the switch turns on after the device has
cooled approximately 20 °C.
The TPS2556/57 also has a second ambient thermal sensor (OTSD2). The ambient thermal sensor turns off the
power switch when the die temperature exceeds 155°C (min) regardless of whether the power switch is in
current limit and will turn on the power switch after the device has cooled approximately 20 °C. The TPS2556/57
continues to cycle off and on until the fault is removed.
APPLICATION INFORMATION
INPUT AND OUTPUT CAPACITANCE
Input and output capacitance improves the performance of the device; the actual capacitance should be
optimized for the particular application. For all applications, a 0.1
μF or greater ceramic bypass capacitor between
IN and GND is recommended as close to the device as possible for local noise decoupling. This precaution
reduces ringing on the input due to power-supply transients. Additional input capacitance may be needed on the
input to reduce voltage overshoot from exceeding the absolute-maximum voltage of the device during heavy
transient conditions. This is especially important during bench testing when long, inductive cables are used to
connect the evaluation board to the bench power supply.
Output capacitance is not required, but placing a high-value electrolytic capacitor on the output pin is
recommended when large transient currents are expected on the output.
10
Copyright 2009, Texas Instruments Incorporated
Product Folder Link(s): TPS2556 TPS2557
相關(guān)PDF資料
PDF描述
TPS658621CZQZR POWER SUPPLY MANAGEMENT CKT, PBGA120
TC54VC5002EMB723 1-CHANNEL POWER SUPPLY SUPPORT CKT, PSSO3
TC54VC5601EZB713 1-CHANNEL POWER SUPPLY SUPPORT CKT, PBCY3
TCM851COA713 SWITCHED CAPACITOR CONVERTER, 120 kHz SWITCHING FREQ-MAX, PDSO8
TC54VC2002ECT713 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO5
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TPS2556DRBEVM-423 功能描述:交換機(jī) IC 開發(fā)工具 Eval Mod for TPS2556 RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:USB Power Switches 工具用于評估:MAX4984E 工作電源電壓:2.8 V to 5.5 V
TPS2556DRBR 功能描述:電源開關(guān) IC - USB Prec Adj Current-Ltd Pwr-Dist Sw RoHS:否 制造商:Micrel 電源電壓-最小:2.7 V 電源電壓-最大:5.5 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:SOIC-8 封裝:Tube
TPS2556DRBT 功能描述:電源開關(guān) IC - USB Prec Adj Current-Ltd Pwr-Dist Sw RoHS:否 制造商:Micrel 電源電壓-最小:2.7 V 電源電壓-最大:5.5 V 最大工作溫度:+ 85 C 最小工作溫度:- 40 C 封裝 / 箱體:SOIC-8 封裝:Tube
TPS2556QDRBRQ1 功能描述:IC PWR DIST SWITCH ADJ 8SON 制造商:texas instruments 系列:汽車級,AEC-Q100 包裝:剪切帶(CT) 零件狀態(tài):有效 開關(guān)類型:通用 輸出數(shù):1 比率 - 輸入:輸出:1:1 輸出配置:高端 輸出類型:N 通道 接口:開/關(guān) 電壓 - 負(fù)載:2.5 V ~ 6.5 V 電壓 - 電源(Vcc/Vdd):不需要 電流 - 輸出(最大值):5A 導(dǎo)通電阻(典型值):22 毫歐 輸入類型:非反相 特性:壓擺率受控型,狀態(tài)標(biāo)志 故障保護(hù):限流(可調(diào)),超溫,UVLO 工作溫度:-40°C ~ 125°C (TJ) 封裝/外殼:8-VDFN 裸露焊盤 供應(yīng)商器件封裝:8-SON(3x3) 標(biāo)準(zhǔn)包裝:1
TPS2557DRBEVM-423 功能描述:交換機(jī) IC 開發(fā)工具 Eval Mod for TPS2557 RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:USB Power Switches 工具用于評估:MAX4984E 工作電源電壓:2.8 V to 5.5 V