参数资料
型号: LTC3677EUFF-3#PBF
厂商: LINEAR TECHNOLOGY CORP
元件分类: 电源管理
英文描述: POWER SUPPLY MANAGEMENT CKT, PQCC44
封装: 7 X 4 MM, 0.75 MM HEIGHT, LEAD FREE, PLASTIC, QFN-44
文件页数: 30/44页
文件大小: 4112K
代理商: LTC3677EUFF-3#PBF
LTC3677-3
36773f
operaTion
PUSHBUTTON INTERFACE OPERATION
State Diagram/Operation
Figure13showstheLTC3677-3pushbuttonstatediagram.
Uponfirstapplicationofpower(VBUS,WALLorBAT)an
internalpower-onreset(POR)signalplacesthepushbut-
toncircuitryintothepower-off(POFF)state.Thefollowing
eventscausethestatemachinetotransitionoutofPOFF
intothepower-up(PUP)state:
1)ONinputLOWfor50ms(PB50MS)
2)PWR_ONinputgoingHIGH(PWR_ON)
Upon entering the PUP state, the pushbutton circuitry
willsequenceupLDO2,Buck1andBuck2inthatorder.
OnesecondafterenteringthePUPstate,thepushbutton
circuitrywilltransitionintothepower-on(PON)state.Note
thatthePWR_ONinputmustbebroughtHIGHbefore
enteringthePONstateifthepartistoremaininthePON
state.Buck3canbeenabledthroughtheEN3inputonce
thepushbuttonisinthePUPorPONstates.
PWR_ONgoingLOW,orVOUTdroppingtoitsundervoltage
lockout(VOUTUVLO)thresholdwillcausethestatemachine
toleavethePONstateandenterthepower-down(PDN)
state.ThePDNstateresetstheI2Cregistersaswellas
disablesBuck1,Buck2andLDO2together.Buck3isalso
disabledinthePDNandPOFFstates.Theoneseconddelay
beforeleavingthepower-downstateallowsthesuppliesto
powerdowncompletelybeforetheycanbere-enabled.
PBSTAT Operation
PBSTATgoesLOW50msaftertheinitialpushbuttonap-
plication(ONLOW)andwillstaylowfor50msminimum.
PBSTATwillgoHIGHcoincidentwithONgoingHIGHunless
ONgoesHIGHbeforethe50msminimumLOWtime.
Hard Reset and PGOOD Operation
Thehardreseteventisgeneratedbypressingandholding
thepushbutton(ONinputLOW)for14seconds.Fora
validhardreseteventtooccurtheinitialpushbuttonap-
plicationmuststartinthePUPorPONstate.Thisavoids
causingahardresetfromoccurringiftheuserhangson
the pushbutton during initial power-up. If a valid hard
reseteventispresentthenthePGOODoutputwilltransi-
tionLOWforabout1.8mstoallowthemicroprocessorto
reset.Thehardreseteventdoesnotaffecttheoperating
stateorregulatoroperation.
ThePGOODpinisanopen-drainoutputusedtoindicate
thatBuck1,Buck2andLDO1areenabledandhavereached
theirfinalregulationvoltage.A230msdelayisincluded
fromthetimeBuck1,Buck2andLDO1reach92%oftheir
regulationvaluetoallowasystemcontrollerampletimeto
resetitself.PGOODisanopen-drainoutputandrequiresa
pull-upresistortoanappropriatepowersource.Optimally
thepull-upresistorisconnectedtotheoutputofBuck1,
Buck2orLDO2sothatpowerisnotdissipatedwhilethe
regulatorsaredisabled.
Pushbutton Operation and VOUT UVLO
As stated earlier VOUTdroppingtoitsUVLOthreshold
willcausethepushbuttontoleavethepower-onstateand
enterthepower-downstate,thuspoweringdownBuck1,
Buck2,Buck3andLDO2.Additionally,LDO1isdisabled
wheninUVLO.Thus,allLTC3677-3suppliesaredisabled
andremaindisabledaslongastheVOUTUVLOcondition
exists.ItisnotpossibletopowerupanyoftheLTC3677-3
generatedsupplieswhileVOUTisbelowtheVOUTUVLO
threshold.
Figure 12. Pushbutton State Diagram
1SEC
POR
35773 F13
1SEC
PB50ms +
PWR_ON
PUP
PON
POFF
PDN
UVLO +
PWR_ON
相关PDF资料
PDF描述
LTC3707IGN 3 A SWITCHING CONTROLLER, 360 kHz SWITCHING FREQ-MAX, PDSO28
LTC3728LIUH 3 A DUAL SWITCHING CONTROLLER, 590 kHz SWITCHING FREQ-MAX, PQCC32
LTC3728LIUH#TR 3 A DUAL SWITCHING CONTROLLER, 590 kHz SWITCHING FREQ-MAX, PQCC32
LTC3770EUH#TR 4 A SWITCHING CONTROLLER, PQCC32
LTC3770EG#TR 4 A SWITCHING CONTROLLER, PDSO28
相关代理商/技术参数
参数描述
LTC3700EMS 功能描述:IC REG DL BUCK/LINEAR 10MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(3),线性(LDO)(2) 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
LTC3700EMS#PBF 功能描述:IC REG DL BUCK/LINEAR 10MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(3),线性(LDO)(2) 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
LTC3700EMS#TR 功能描述:IC REG DL BUCK/LINEAR 10MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(3),线性(LDO)(2) 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
LTC3700EMS#TRPBF 功能描述:IC REG DL BUCK/LINEAR 10MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压(降压)同步(3),线性(LDO)(2) 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:*
LTC3701EGN 功能描述:IC REG CTRLR BUCK PWM CM 16-SSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)