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M ake su re th a t you obtai n ed th i s pu bl i cati on from an au th ori zed d i s tri bu tor ® Registered trademark of the International Electrotechnical Commission –2– I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 INTERNATI ONAL ELECTROTECHNI CAL COMMISSI ON U N I VE RS AL S E RI AL B U S I N T E RF AC E S F O R D AT A AN D P O WE R – P a rt -1 : C o m m o n c o m p o n e n ts – U S B B a t te ry C h a rg i n g S p e c i fi c a ti o n , Re vi s i o n FOREWORD ) The I nternati on al Electrotechni cal Comm ission (I EC) is a worl d wid e organization for stan dardization com prisin g all n ation al el ectrotechnical comm ittees (I EC National Comm ittees) The object of I EC is to prom ote internati onal co-operation on all questions concerni ng stand ardi zati on in the el ectrical an d electronic fields To this end and in additi on to other acti vities, I EC publish es I nternational Stan dards, Techn ical Specifications, Technical Reports, Publicl y Avail abl e Specificati ons 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em ployees, servants or ag ents inclu din g in divi du al experts an d m em bers of its technical com m ittees and I EC Nati on al Com m ittees for any person al i njury, property d am age or other dam age of any nature whatsoever, wheth er di rect or indirect, or for costs (includ i ng leg al fees) and expenses arisi ng out of the publ ication, use of, or relian ce upon, this I EC Publicati on or any other I EC Publications 8) Attention is drawn to th e N orm ative references cited in th is publ ication Use of the referenced publ ications is indispensable for the correct applicati on of this publication 9) Attention is drawn to the possibility that som e of the elem ents of this I EC Publication m ay be the su bject of patent rig hts I EC shall not be held responsibl e for identifyi ng any or all such patent ri ghts I nternational Standard I EC 62680-1 -1 has been prepared by technical area 4: I nterfaces and methods of m easurem ent for personal com puting equipment, of I EC technical committee 00: Audio, video and multimedia system s and equipment The text of this standard is based on docum ents prepared by the U SB I m plementers Forum (U SB-I F) The structure and editorial rules used in this publication reflect the practice of the organization which subm itted it I EC 62680-1 -1 : 201 © I EC 201 –3– © U SB-I F 201 The text of this standard is based on the following documents: CDV Report on votin g 00/2330/CDV 00/2433/RVC Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table A list of all the parts in the I EC 62680 series, published under the general title bus interfaces for data and power can be found on the I EC website Universal serial The comm ittee has decided that the contents of this publication will remain unchanged until the stability date indicated on the I EC website under "http: //webstore.iec ch" in the data related to the specific publication At this date, the publication will be • • • • reconfirmed, withdrawn, replaced by a revised edition, or am ended A bilingual version of this publication m ay be issued at a later date I M P O RT AN T – T h e ' c o l o u r i n s i d e ' th at it co n tai n s u n d e rs t a n d i n g c o l o u r p ri n t e r of c o l o u rs i ts wh i c h c o n te n ts l og o a re U s e rs on th e co ve r p a g e o f th i s c o n s i d e re d sh ou l d to t h e re fo re be p u b l i c ati o n u s e fu l p ri n t th i s fo r i n d i c ate s th e d o cu m en t c o rre c t u si n g a –4– I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 INTRODUCTION The I EC 62680 series is based on a series of specifications that were originally developed by the U SB I m plementers Forum (U SB-I F) These specifications were subm itted to the I EC under the auspices of a special agreement between the I EC and the U SB-I F The U SB I mplem enters Forum , I nc.(U SB-I F) is a non-profit corporation founded by the group of companies that developed the U niversal Serial Bus specification The USB-I F was form ed to provide a support organization and forum for the advancem ent and adoption of U niversal Serial Bus technolog y The Forum facilitates the development of high-quality com patible U SB peripherals (devices), and promotes the benefits of USB and the quality of products that have passed com pliance testing AN Y U SB S P E C I F I C AT I O N S W H AT S O E V E R, I N F RI N G E M E N T , OR F O RU M AL L I N CLU DI N G L I AB I L I T Y , R E L AT I N G P RO VI D E D AN Y FI TN E S S I M P L E M E N TE RS RI G H T S , AR E IN CLU DIN G AN D FOR TH E U SE AN Y U SB AN Y AU T H O R S L I AB I L I T Y TO OR TO YO U W AR R AN T Y FOR " AS OF IS, " WI T H P ART I C U L AR OF AN Y U SB W AR R AN T I E S P U RP O S E OR OF AN Y N ON - TH E S P E C I F I C AT I O N S I N F RI N G E M E N T I M P L E M E N T AT I O N NO M E R C H AN T AB I L I T Y , U SB D I S C L AI M P R O P R I E T AR Y I N F O R M AT I O N IN TH I S S P E C I F I C AI T O N TH E WI T H P RO VI S I O N AN Y OF LI C EN SE, E XP RE S S S P E C I F I C AT I O N S OR I M PLI E D, BY TO YO U DOES E STOPPEL OR N OT P RO VI D E O T H E RW I S E , TO YO U AN Y I N T E L L E C T U AL P RO P E RT Y R I G H T S Entering into U SB Adopters Agreements may, however, allow a signing compan y to participate in a reciprocal, royalty-free licensing arrangem ent for com pliant products For more information, please see: http://www usb.org/developers/docs/ http://www usb.org/developers/devclass_docs#approved I EC DOES NOT TAKE AN Y POSI TI ON AS TO WHETH ER I T I S ADVI SABLE FOR YOU TO ENTER I NTO AN Y U SB ADOPTERS AGREEMENTS OR TO PARTI CI PATE I N TH E U SB I MPLEMENTERS FORU M.” This series covers the U niversal Series Bus interfaces for data and power and consists of the following parts: Universal Serial Bus interfaces for data and power – Part 1-1: Common components – USB Battery Charging Specification, Revision 1.2 I EC 62680-1 -1 , IEC 62680-2-1 , Universal Serial Bus interfaces for data and power – Part 2-1: Universal Serial Bus Specification, Revision 2.0 IEC 62680-2-2, Universal Serial Bus interfaces for data and power – Part 2-2: USB MicroUSB Cables and Connectors Specification, Revision 1.01 Universal Serial Bus interfaces for data and power – Part 2-3: Universal Serial Bus Cables and Connectors Class Document Revision 2.0 I EC 62680-2-3, This part of the I EC 62680 series consists of several distinct parts: • the m ain bod y of the text, which consists of the original specification and all ECN and Errata developed by the USB-I F I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 –5– CONTENTS FOREWORD I NTRODUCTI ON I ntroduction 1 Scope Background 3 Reference Documents Definitions of Terms Accessory Charger Adaptor ACA-Dock Attach versus Connect 4 Charging Downstream Port Charging Port Dead Battery Threshold Dedicated Charging Port Downstream Port Micro ACA Portable Device 1 Rated Current Standard ACA Standard Downstream Port 4 USB Charger Weak Battery Threshold 5 Parameter Values 6 OTG Considerations Super Speed Considerations Dead Battery Provision Background 2 DBP – Unconfigured Clause DBP – Configured Clause Charging Port Detection Overview Charger Detection H ardware Overview 2 VBU S Detect 20 3 Data Contact Detect 20 Prim ary Detection 23 Secondary Detection 30 ACA Detection 32 3 Charger Detection Algorithm s 34 3 Weak Battery Algorithm 34 3 Good Battery Algorithm 35 Charger Detection Tim ing 36 Data Contact Detect Timing 36 Detection Timing, CDP 38 Ground Current and N oise M argins 40 Charging Port and Portable Device Requirements 40 –6– I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 4 Charging Port Requirements 40 Overshoot 40 Maxim um Current 40 Detection Renegotiation 40 Shutdown Operation 41 Failure Voltage 41 Multiple Ports 41 Charging Downstream Port 41 Required Operating Range 41 2 Shutdown Operation 42 Undershoot 42 4 Detection Signaling 42 Connector 43 ACA-Dock 43 Required Operating Range 43 Undershoot 43 3 Detection Signaling 43 4 Connector 43 4 Dedicated Charging Port 43 4 Required Operating Range 43 4 Undershoot 44 4 Detection Signaling 44 4 Connector 44 Accessory Charger Adapter 45 Required Operating Range 45 Undershoot 45 Detection Signaling 45 Connector 45 Portable Device 45 Allowed Operating Range 45 Detection Signaling 46 Detection Renegotiation 46 Connector 47 Parameter Values 47 Accessory Charger Adapter 50 I ntroduction 50 Micro ACA 52 Micro ACA Ports 52 2 Micro ACA Connectivity Options 53 Micro ACA Architecture 53 Micro ACA Modes of Operation 54 I m plications of not Supporting Micro ACA Detection 56 6 Micro ACA Requirements 56 Portable Device State Diagram 57 Standard ACA 59 Standard ACA Ports 59 Standard ACA Architecture 60 3 Standard ACA Modes of Operation 62 I m plications of not Supporting Standard ACA Detection 62 I EC 62680-1 -1 : 201 © I EC 201 –7– © U SB-I F 201 Standard ACA Requirements 62 Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Figure Table Table Table Table Table Table Table Table Table 3-1 – System Overview 3-2 – Charger Detection H ardware 3-3 – Data Pin Offset 20 3-4 – Data Contact Detect, N ot Attached 21 3-5 – Data Contact Detect, Standard Down stream Port 22 3-6 – Prim ary Detection, DCP 23 3-7 – Prim ary Detection, CDP 25 3-8 – Prim ary Detection, SDP 26 3-9 – Prim ary Detection, ACA-Dock 27 3-1 – Primary Detection, ACA 29 3-1 – Secondary Detection, DCP 30 3-1 – Secondary Detection, CDP 31 3-1 – ACA Detection 33 3-1 – Weak Battery Algorithm 34 3-1 – Good Battery Algorithm 35 3-1 – DCD Tim ing, Contact After Start 37 3-1 – DCD Tim ing, Contact Before Start 37 3-1 – DCD Tim ing, N o Contact 38 3-1 – Detection Tim ing, CDP 39 4-1 – CDP Required Operating Range 42 4-2 – DCP Required Operating Range 44 4-3 – Portable Device Allowed Operating Range 46 6-1 – Accessory Charger Adapter 51 6-2 – Micro ACA Ports 52 6-3 – Micro ACA Architecture 54 6-4 – Portable Device State Diagram 58 6-5 – Standard ACA Ports 59 6-6 – Standard ACA Architecture 61 5-1 5-2 5-3 5-4 5-5 6-1 6-2 6-3 6-4 – Voltages 47 – Currents 48 – Resistances 49 – Capacitances 49 – Times 50 – Micro ACA Connectivity Options 53 – Micro ACA Modes of Operation 55 – Standard ACA Connectivity Options 60 – Standard ACA Modes of Operation 62 –8– I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 B a t te ry C h a rg i n g S p e c i fi c a ti o n ( I n c l u d i n g e rra ta a n d E C N s t h ro u g h M a rc h , 2 ) Re vi s i o n M a rc h , 2 C o p yri g h t © 2 , U S B I m p l e m e n te rs F o ru m , I n c Al l ri g h ts re s e rve d A LI CEN SE I S H EREBY GRANTED TO REPRODUCE THI S SPECI FI CATI ON FOR I NTERN AL USE ONLY NO OTHER LI CEN SE, EXPRESS OR I MPLI ED, BY ESTOPPEL OR OTHERWI SE, I S GRANTED OR I NTEN DED H EREBY USB-I F AN D TH E AU THORS OF THI S SPECI FI CATI ON EXPRESSLY DI SCLAI M ALL LI ABI LI TY FOR I NFRI N GEM ENT OF I NTELLECTUAL PROPERTY RI GH TS, RELATI N G TO I MPLEMENTATI ON OF I NFORM ATI ON I N THI S SPECI FI CATI ON USB-I F AND TH E AUTHORS OF TH I S SPECI FI CATI ON ALSO DO NOT WARRANT OR REPRESENT THAT SU CH I MPLEMENTATI ON(S) WI LL NOT I NFRI NGE THE I NTELLECTUAL PROPERTY RI GHTS OF OTH ERS THI S SPECI FI CATI ON I S PROVI DED "AS I S” AND WI TH NO WARRAN TI ES, EXPRESS OR I MPLI ED, STATUTORY OR OTH ERWI SE ALL WARRANTI ES ARE EXPRESSLY DI SCLAI MED NO WARRANTY OF MERCH ANTABI LI TY, NO WARRANTY OF NONI NFRI NGEMENT, NO WARRANTY OF FI TN ESS FOR AN Y PARTI CU LAR PURPOSE, AND NO WARRANTY ARI SI N G OUT OF AN Y PROPOSAL, SPECI FI CATI ON, OR SAMPLE I N N O EVENT WI LL U SB-I F OR U SB-I F MEM BERS BE LI ABLE TO AN OTHER FOR TH E COST OF PROCURI NG SU BSTI TUTE GOODS OR SERVI CES, LOST PROFI TS, LOSS OF USE, LOSS OF DATA OR AN Y I NCI DENTAL, CON SEQU ENTI AL, I NDI RECT, OR SPECI AL DAMAGES, WHETHER U NDER CONTRACT, TORT, WARRANTY, OR OTH ERWI SE, ARI SI NG I N AN Y WAY OUT OF TH E U SE OF THI S SPECI FI CATI ON , WHETHER OR NOT SU CH PARTY H AD ADVAN CE NOTI CE OF THE POSSI BI LI TY OF SUCH DAMAGES – 52 – 6.2 Micro ACA 6.2.1 I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 Micro ACA Ports Figure 6-2 shows the ports of a Micro ACA IEC Figure 6-2 – Micro ACA Ports Various cables can be uses to attach the Accessory Port of a Micro ACA to an accessory, including: • • • • M icro-A to Micro-A to Micro-B to Micro-B to M icro-B captive Standard-A Micro-A A Micro ACA shall have one of the following m echanical interfaces for its Charger Port: • • • M icro-B receptacle Captive cable terminating in a Standard-A plug Captive cable terminating in a charger I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 6.2.2 – 53 – Micro ACA Connectivity Options Table 6-1 shows the different combinations of devices that can be attached to each Micro ACA port, and provides comm ents on their operation Table 6-1 – Micro ACA Connectivity Options OTG Port Charger Port Accessory Port HNP Support SRP Support OTG Dev Charges From Accessory Draws Current From nothi ng Chargi ng Port B-dev - - - Charg er Port nothi ng Chargi ng Port A-dev - - - - OTG dev nothi ng B-dev yes yes - OTG Port OTG dev nothi ng A-dev yes yes Accessory Port - OTG dev nothi ng charg er - - Accessory Port - OTG dev PC, OTG dev nothi ng - - - - OTG dev PC, OTG dev B-dev yes yes - OTG Port OTG dev PC, OTG dev A-dev yes yes Accessory Port - OTG dev PC, OTG dev charg er - - Accessory Port - OTG dev Chargi ng Port nothi ng - - Charg er Port - OTG dev Chargi ng Port B-dev yes no Charg er Port Charg er Port OTG dev Chargi ng Port A-dev yes yes Charg er Port - OTG dev Chargi ng Port charg er - - Charg er Port - An ACA does not allow data comm unication through the Charger Port The ACA only allows charging from the Charger Port when a Charging Port is attached I t does not allow charging from the Charger Port wh enever an SDP or an OTG device is attached I n the case where both an OTG device and a B-device are charging from the Charger Port, it is not necessary to support SRP, since VBU S is alread y asserted at both the OTG Port and Accessory Port The OTG device is required to lim it the current it draws from the ACA such that VBU S_OTG remains above VACA_OPR 6.2.3 Micro ACA Architecture Figure 6-3 shows the architecture of a Micro ACA – 54 – I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 IEC Figure 6-3 – Micro ACA Architecture The Accessory Switch allows current to flow between VBU S_OTG and VBU S_ACC The Charger Switch allows current to flow from VBU S_CHG and VBU S_OTG The Adapter Controller performs several functions These functions include: • • • • • • sensing the state of the I D_ACC pin, (grounded or floating) outputting a state onto the I D_OTG pin, (R I D_GN D , R I D_A , R I D_B , R I D_C or R I D_FLOAT ) using the DP_CHG and DN _CHG pins to detect if a Charging Port is attached to the Charger Port sensing the voltage on the VBUS_ACC pin sensing the voltage on the VBUS_OTG pin controlling the Charger and Accessory Switches 6.2.4 Micro ACA Modes of Operation The operation of the Micro ACA is shown in Table 6-2, and is described below The table assum es that an OTG device is always attached to the OTG Port I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 – 55 – T a b l e - – M i c ro AC A M o d e s o f O p e t i o n Ro w C h a rg e r Ac c e s s o r y VB U S _ VB U S _ ID_ P o rt P o rt AC C O TG AC C C h a rg e r S wi tc h ) Ac c e s s S wi tch ) I D _O T G 2) O TG D e vi ce not Ch rg Port nothi ng low low float open ADP-pass R I D_FLOAT B-dev 2a not Ch rg Port B-device low low groun d open ADP-pass R I D_GND A-dev 2b not Ch rg Port B-device dri ven high groun d open closed R I D_GND A-dev not Ch rg Port A-dev off low low float open ADP-pass R I D_FLOAT B-dev not Ch rg Port A-dev on high dri ven 4) float open closed R I D_FLOAT B-dev Chargi ng Port nothi ng low dri ven 5) float closed open R I D_B B-dev Chargi ng Port B-device dri ven dri ven 5) ground closed closed R I D_A A-dev Chargi ng Port A-dev off low dri ven 5) float closed open R I D_B B-dev Chargi ng Port A-dev on high dri ven 5) float closed open R I D_C B-dev 3) 6) Notes ) Open refers to the hig h im pedance state of the switch Closed refers to the low im pedance state of the switch 2) ADP-pass refers to an im ped ance state of th e switch sufficiently l ow to transm it ADP probes (RADP_OTG_ACC) 3) Dri ven vi a Accessory Switch from VBUS_OTG 4) Dri ven vi a Accessory Switch from VBUS_ACC 5) Dri ven vi a Ch arger Switch from VBUS_CHG 6) Dri ven vi a Ch arger Switch and Accessory Switch from VBUS_CHG 7) I n row 2a, the VBUS_OTG low state can happen after TA_WAI T_BCON m ax of I D_OTG goi ng low, if the OTG A-device supports sessions (See OTG Supplem ent for val ue ) 8) Other transitory states exist when m ovi ng between th e d esig n states shown i n th e rows of the table I t is th e responsibil ity of th e M icro ACA design er to take these i nto account I n rows and 7, a Charging Port is attached to the Micro ACA Charger Port, and either nothing is attached to the Accessory Port, or an A-device that is not asserting VBU S is attached to the Accessory Port The I D resistance of R I D_B indicates to the OTG device that it is allowed to charge, and that it is allowed to initiate SRP The OTG device is not allowed to connect, (that is, leave DP_OTG asserted) The reason for this is that if an A-device is on the Accessory Port and is not asserting VBU S, then the U SB spec requires the data lines remain at a logic low I n row 8, a Charging Port is attached to the Micro ACA Charger Port, and an A-device that is asserting VBU S is attached to the Accessory Port The I D resistance of R I D_C indicates to the OTG device that it is allowed to charge, and that it is allowed to connect H owever, it is not allowed to SRP, since the A-device is alread y asserting VBU S I n row 6, a Charging Port is attached to the Micro ACA Charger Port, and a B-device is attached to the Accessory Port The I D resistance of R I D_A indicates to the OTG device that it is allowed to charge, and that it should default to acting as host – 56 – I m p l i c a t i o n s o f n o t S u p p o rt i n g I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 M i c ro AC A D e t e c t i o n The OTG supplement onl y defines the floating and ground states on the I D pin The floating state is an y im pedance greater than M, and the ground state is an y impedance less than Ω Since the R I D_A , R I D_B and R I D_C resistances are between the floating and ground resistance values, an OTG device that does not support ACA detection could interpret an y of these values as either floating or ground I f an OTG device interpreted the R I D_A resistance as floating, then: • • it would not be aware of the opportunity to draw I DEV_CHG from VBUS it would default to peripheral, when it should default to host I f an OTG device interpreted the R I D_B resistance as grounded, then: • • it would try to drive VBU S_OTG at the same tim e as the ACA was driving VBU S_OTG it would default to host, when it should default to peripheral I f an OTG device interpreted the R I D_B resistance as floating, then: • • • it would not be aware of the opportunity to draw up to I DEV_CHG from VBU S it would not be aware of the opportunity to SRP it would be required to connect, and potentiall y violate the U SB back-drive voltage spec I f an OTG device interpreted the R I D_C resistance as grounded, then: • • it would try to drive VBU S_OTG at the same tim e as the ACA was driving VBU S_OTG it would default to host, when it should default to peripheral I f an OTG device interpreted the R I D_C resistance as floating, then: • it would not be aware of the opportunity to draw up to I DEV_CHG from VBU S 6 M i c ro AC A R e q u i re m e n t s A Micro ACA Charger Port shall draw less than I SUSP when an ything other than a Charging Port is attached to it A Micro ACA shall draw less than I SUSP when a Charging Port is attached to the ACA Charger Port and nothing is attached to the OTG Port or Accessory Port The resistance between the VBU S_CHG and VBU S_OTG pins of an ACA shall be R ACA_CHG_OTG when the Charger Switch is closed in rows 5-8 of Table 6-2, and the voltage on VBU S_CHG is at V ACA_OPR The resistance between the VBU S_CHG and VBU S_ACC pins of an ACA shall be R ACA_CHG_ACC when both the Charger Switch and the Accessory Switch are closed in row of Table 6-2, and the voltage on VBU S_CH G is at V ACA_OPR The resistance between the VBU S_OTG and VBU S_ACC pins of an ACA shall be R ACA_OTG_ACC when the Charger Switch is open and the Accessory Switch is closed in rows 2b and of Table 6-2 and the voltage on either VBU S_ACC or VBU S_OTG is at V ACA_OPR The resistance between the VBU S_OTG and VBU S_ACC pins of an ACA shall be R ADP_OTG_ACC when the Accessory Switch is in condition ADP-pass in rows , 2a or of Table 6-2 I EC 62680-1 -1 : 201 © I EC 201 – 57 – © U SB-I F 201 The resistance between the internal ground of the Micro ACA and the ground pin of a MicroAB receptacle attached to the OTG port of an ACA shall be R OTG_ACA_GN D This requirement lim its the difference between OTG and ACA ground under conditions of high chargin g current This in turn allows the OTG device to reliabl y detect the ACA I D resistance under conditions of high charging current When a M icro ACA detects VBU S_CHG asserted, it shall output V DP_SRC on DP_CHG I f the ACA detects DN_CH G greater than V DAT_REF , then it is allowed to close its Charger Switch for as long as VBU S_CHG remains above VOTG_SESS_VLD Note that this could result in the ACA drawing more than I CFG_MAX from a PS2 port I f the Charger Port was attached to a CDP, then it's possible that DN _CHG may go below V DAT_REF of the ACA due to charging currents causing the CDP ground to be lower than the ACA ground I t’s also possible that the CDP could issue a U SB reset The ACA shall ignore either of these effects, and continue to leave its Charger Switch closed When VBU S_CHG goes below V OTG_SESS_VLD , then the ACA is required to again check for VDN_CH G being greater than VDAT_REF , before opening the Charger Switch The M icro ACA is required to have a capacitance of C MACA_VBUS on both the VBU S_OTG and VBU S_ACC pins The reason for this is so that attached devices which support the Attach Detection Protocol (ADP) defined in OTG can detect when they are attached to an ACA Portabl e Devi ce State Diag ram Figure 6-4 shows the state diagram for a PD attached to an SDP, CDP, DCP, Micro ACA, ACA-Dock or B-device – 58 – I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 IEC Figu re 6-4 – Portable Devi ce State Diagram Each bubble represents a state of the PD The first row in each bubble is the state num ber The first term in the second row indicates whether the attached device is acting like a Charging Port The second term in the second row indicates what would be attached to the Accessory Port of the ACA, if the PD is attached to an ACA The third row indicates whether or not the attached device is driving the PD VBU S pin The fourth row indicates what resistance the attached device is appl ying to the PD I D pin I n state 2, the fifth row indicates that the ACA-Dock is outputting a voltage of V DM_SRC to the D- pin of the PD I n state , the PD detects that it is not attached to an ything, or that it is attached to som ething that is not driving VBU S or pulling I D low I n state 2, the PD is attached to an ACA-Dock that is driving VBU S I f the PD is rem oved from the ACA-Dock, or if the ACA-Dock stops providing VBUS, the PD transitions to state An ACA-Dock is required to let its I D pin float if it is not driving VBU S I f the ACA-Dock were to ground the I D pin while it was not driving VBU S, then the PD would incorrectl y transition to state 7, where it would attem pt to drive VBU S into the ACA-Dock I EC 62680-1 -1 : 201 © I EC 201 – 59 – © U SB-I F 201 In state 3, the PD is attached directl y to an A-device, or to an ACA that has an A-device on its Accessory Port I n either case, the PD is drawing current from the A-device, and not from the ACA Charger Port This is wh y the second row has the term ! Chg I f the A-device presents itself to the PD as a CDP, then the PD can draw I DEV_CH G from the A-device I n state 4, the PD is attached to an ACA that has a charger on its Charger Port, and an Adevice on its Accessory Port Detaching the PD from the ACA causes the PD to transition to state I n state 5, the PD is attached to an ACA that has a charger on its Charger Port, and does not have an accessory on its Accessory Port I n state 6, the PD is attached to an ACA that has a charger on its Charger Port, and a Bdevice on its Accessory Port Detaching the PD from the ACA causes the PD to transition to state I n state 7, the PD is attached to a B-device, or to an ACA that has a B-device on its Accessory Port This is the onl y state in which the PD is required to output power on VBU S I n states to 6, the PD is able to draw power from VBU S 6.3 Standard ACA 6.3.1 Standard ACA Ports Figure 6-5 shows the ports of a Standard ACA IEC Figure 6-5 – Standard ACA Ports Various cables can be uses to attach the Accessory Port of a Standard ACA to an accessory, including: • • • Standard-A to M icro-B Standard-A to Standard-B Standard-A to captive A Standard ACA shall have one of the following mechanical interfaces for its Charger Port: – 60 – • • • I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 Micro-B receptacle Captive cable term inating in a Standard-A plug Captive cable terminating in a charger Table 6-3 – Standard ACA Connectivity Options OTG Port Charger Port Accessory Port HNP Support SRP Support OTG Dev Charges From Accessory Draws Current From nothi ng Chargi ng Port B-dev – – – Charg er Port OTG dev nothi ng B-dev yes yes – OTG Port – OTG dev PC, OTG dev nothi ng – – – – OTG dev PC, OTG dev B-dev yes yes – OTG Port OTG dev Chargi ng Port nothi ng – – Charg er Port – OTG dev Chargi ng Port B-dev yes no Charg er Port Charg er Port An ACA does not allow data comm unication through the Charger Port The ACA only allows charging from the Charger Port when a Charging Port is attached I t does not allow charging from the Charger Port wh enever an SDP or an OTG device is attached I n the case where both an OTG device and a B-device are charging from the Charger Port, it is not necessary to support SRP, since VBU S is alread y asserted at both the OTG Port and Accessory Port The OTG device is required to limit the current it draws from the ACA such that VBU S_OTG remains above V ACA_OPR 6.3.2 Standard ACA Architecture Figure 6-6 shows the architecture of a Standard ACA I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 – 61 – IEC Figure 6-6 – Standard ACA Architecture The Charger Switch allows current to flow from VBU S_CHG and VBU S_OTG Note that unlike the Micro ACA, the Standard ACA does not have an Accessory Switch The Standard ACA is required to have a capacitance of C SACA_VBUS on the VBU S_OTG or VBU S_ACC pins The reason for this is as follows The Accessory Port does not have an I D pin, since it uses a Standard-A receptacle Thus, the Standard ACA cannot detect when a plug has been inserted into the Accessory Port, and therefore it cannot inform the OTG Device of such an attach event I f a Charging Port were attached to the ACA Charger Port, then the accessory would connect, and the OTG device could detect the connect event I f a Charging Port were not attached to the ACA Charger Port, then the OTG Device would either have to leave VBU S asserted, or it would have to ADP I n order to allow ADP to work, the combined capacitance on the VBU S_OTG and VBU S_ACC pins needs to be C SACA_VBUS The Adapter Controller performs several functions These functions include: • • • outputting a state onto the I D_OTG pin, (R I D_GN D , R I D_A ) using the DP_CHG and DN _CHG pins to detect if a Charging Port is attached to the Charger Port controlling the Charger Switch – 62 – 3 S t a n d a rd I EC 62680-1 -1 : 201 © I EC 201 © U SB-I F 201 AC A M o d e s o f O p e t i o n The operation of the Standard ACA is shown in Table 6-4, and is described below The table assum es that an OTG device is always attached to the OTG Port T a b l e - – S t a n d a rd Ro w C h a rg e r AC A M o d e s o f O p e t i o n Ac c e s s o r y P o r t C h a rg e r P o rt I D _O T G O TG D e vi ce S wi tch N o te 1 non -charg er nothi ng open non -charg er B-device open charg er nothi ng closed charg er B-device closed NOTE switch R I D_GND R I D_GND R I D_A R I D_A A-dev A-dev A-dev A-dev Open refers to the hi gh im pedance state of the switch Closed refers to the low im ped ance state of the When a PD is attached to a Standard ACA, the I D_OTG pin is either at R I D_GN D or at R I D_A , and the PD is always acting as an A-device I m p l i c a t i o n s o f n o t S u p p o rt i n g S t a n d a rd AC A D e t e c t i o n The OTG supplement onl y defines the floating and ground states on the I D pin The floating state is an y impedance greater than M, and the ground state is an y impedance less than Ω Since the R I D_A is between the floating and ground resistance values, an OTG device that does not support ACA detection could intepret this value as either floating or ground I f an OTG device interpreted the R I D_A resistance as floating, then: • • it would not be aware of the opportunity to draw I DEV_CHG from VBUS, it would default to peripheral, when it should default to host S t a n d a rd AC A R e q u i re m e n t s A Standard ACA Charger Port shall draw less than I SUSP when an ything other than a Charging Port is attached to it A Standard ACA Accessory Port shall draw less than I SUSP when a Charging Port is attached to the ACA Charger Port and nothing is attached to the OTG Port or Accessory Port The resistance between VBU S_CHG, and either VBU S_OTG or VBUS_ACC of a Standard ACA shall be R ACA_CHG_OTG when the Charger Switch is closed in Table 6-1 , and the voltage on VBU S_CHG is at VACA_OPR The resistance between the internal ground of the Standard ACA and the ground pin of a Micro-AB receptacle attached to the OTG port of an ACA shall be R OTG_ACA_GN D This requirement limits the difference between OTG and ACA ground under conditions of high charging current This in turn allows the OTG device to reliabl y detect the ACA I D resistance under conditions of high charging current When a Standard ACA detects VBU S_CHG asserted, it shall output V DP_SRC on DP_CHG I f the ACA detects DN _CH G greater than V DAT_REF , then it shall close its Charger Switch for as long as VBU S_CHG remains above VOTG_SESS_VLD N ote that this could result in the ACA drawing m ore than I CFG_MAX from a PS2 port I EC 62680-1 -1 : 201 © I EC 201 – 63 – © U SB-I F 201 If the Charger Port was attached to a CDP, then it's possible that DN _CHG may go below V DAT_REF of the ACA due to charging currents causing the CDP ground to be lower than the ACA ground I t’s also possible that the CDP could issue a U SB reset The ACA shall ignore either of these effects, and continue to leave its Charger Switch closed When VBU S_CHG goes below V OTG_SESS_VLD , then the ACA is required to again check for VDN_CH G being greater than VDAT_REF , before opening the Charger Switch _ INTERNATIONAL ELECTROTECHNICAL COMMISSI ON 3, rue de Varembé PO Box 31 CH-1 21 Geneva 20 Switzerland Tel: + 41 22 91 02 1 Fax: + 41 22 91 03 00 info@iec.ch www.iec.ch