United States Patent (19)
`Theobald
`
`54 ACCESSORY IDENTIFICATION APPARATUS
`AND METHOD
`75 Inventor: David J. Theobald, Woodstock, Ill.
`
`73 Assignee: Motorola, Inc., Schaumburg, Ill.
`
`21 Appl. No.: 895,391
`
`Jul. 16, 1997
`22 Filed:
`(51) Int. Cl. ............................................... HO1M 10/46
`52 U.S. Cl. .............................................................. 320/106
`58 Field of Search ..................................... 320/106, 110,
`320/132, DIG. 12, DIG. 21, 105, 114, 147
`
`56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`5,164,652 11/1992 Johnson et al. ............................. 320/2
`5,184,059 2/1993 Patino et al. .............................. 320/15
`5,313,661
`5/1994 Malmi et al..
`5,489,834 2/1996 Pitkanen................. 320/15
`
`5,460,901 10/1995 Syrjala - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 429/90
`
`5,546,317 8/1996 Andrieu - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 364/481
`
`FOREIGN PATENT DOCUMENTS
`2 239 567 7/1991 United Kingdom.
`
`USOO5859522A
`Patent Number:
`11
`(45) Date of Patent:
`
`5,859,522
`Jan. 12, 1999
`
`OTHER PUBLICATIONS
`Motorola Product List Web Page, Motorola Original Adapt
`ers, Personal Cellular Phone Adapters, p. 1, 1997.
`Motorola Product List Web Page, Motorola Original Hands
`Free Systems, Personal Cellular Phone Hands Free Solu
`tions, p. 1, 1997.
`Motorola Product List Web Page, Motorola Original Charg
`ers, Personal Cellular Phone Chargers, pp. 1 & 2, 1997.
`Primary Examiner Edward H. Tso
`Attorney, Agent, or Firm Mark D. Patrick
`57
`ABSTRACT
`An accessory identification apparatus (195) used in an
`electronic device (102) includes a connector (122) to couple
`to an accessory (104) and a controller (108) coupled to the
`connector (122). The connector (122) includes an informa
`tion pin (124) to receive information generated from opera
`tion of the accessory (104). The controller (108) identifies
`the accessory (104) from a voltage level generated by
`attachment of the accessory (104) to the information pin
`(124). Also, an accessory identification apparatus (195) used
`in an accessory (104) includes a connector (173) to couple
`to an electronic device (102) and an identification element
`(174) coupled to the connector (173). The connector (173)
`generated from operation of the accessory (104). The iden
`(173) to the electronic device (102), provides an identity of
`the accessory (104) via the information pin (179).
`6 Claims, 2 Drawing Sheets
`
`tification element (174), upon attachment of the COnnectOr
`
`includes
`
`information pin (179) to Supply information
`
`20
`
`200
`
`BATTERY
`NTH
`YES
`
`ACCESSORY
`ATTACHED
`
`YES
`READ YOLAGE
`ON AUDO
`
`WOLTACE
`ON AUDIO
`IN LINE BETEEN
`Y AND Y2
`
`
`
`
`
`ON AUDIO
`IN
`NE BETEEN
`W3 Ap W.
`
`YES
`IDENTIF ACCESSORY
`ASFASTRATE CHARGER
`
`210
`
`BAFTERY
`WOTAGE AND
`
`
`
`BATTERY
`FULY
`Act
`
`SEND CHARGER
`ENABLE SIGNAL
`TO CONTROL, SWITCH
`
`
`
`
`
`
`
`
`
`
`
`
`
`Fundamental Ex 2007-p 1
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`U.S. Patent
`
`Jan. 12, 1999
`
`Sheet 1 of 2
`
`5,859,522
`
`
`
`Fundamental Ex 2007-p 2
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`U.S. Patent
`
`Jan. 12, 1999
`
`Sheet 2 of 2
`
`5,859,522
`
`BATTERY
`THE
`
`ACCE
`ATTACHED
`
`201
`
`
`
`202
`
`READ VOLTACE
`ON AUDIO
`IN LINE
`
`
`
`
`
`
`
`VOLTACE
`ON AUDIO
`IN LINE BETWEEN
`W AND W2
`
`
`
`FI G. 2
`
`206
`
`VOLTAGE
`ON AUDIO
`IN LINE BETWEEN
`W AND W4
`
`IDENTIFY ACCESSORY
`AS VID RATE CHARGER
`
`IDENTIFY ACCESSORY
`AS FAST RATE CHARGER
`
`
`
`
`
`
`
`
`
`
`
`BATTERY
`VOLTAGE AND
`TEP IN RANGE TO
`CHRCE
`
`BATTERY
`FULLY
`CHARGED
`
`
`
`SEND CHARGER
`ENABLE SIGNAL
`TO CONTROL SWITCH
`
`
`
`Fundamental Ex 2007-p 3
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`5,859,522
`
`1
`ACCESSORY IDENTIFICATION APPARATUS
`AND METHOD
`
`FIELD OF THE INVENTION
`This invention relates generally to electronic devices and
`accessories therefor and, more particularly, to an apparatus
`and method used to identify an accessory to an electronic
`device.
`
`2
`to receive information generated from operation of the
`accessory, a low cost and backwards compatible accessory
`identification System is realized.
`FIG. 1 illustrates an accessory identification system 100.
`The accessory identification system 100 includes an elec
`tronic device 102, a battery 103, and an accessory 104. The
`electronic device 102 communicates with a base station 101,
`which provides wireleSS communications and features, Such
`as paging, telephone, and short messaging, or the like, to the
`electronic device 102 when it is located within a geographic
`area served by the base station 101. The base station 101 and
`the electronic device 102 communicate with each other via
`a communication link, which is preferably radio frequency
`(RF) signals 105. In the illustrated embodiment, the elec
`tronic device 102 is a cellular telephone and the base station
`101 is a cellular telephone service provider.
`The electronic device 102 includes an antenna 106, a
`receiver 107, a controller 108, a memory 109, a speaker 110,
`a microphone 111, and a transmitter 112. The controller 108
`includes a microprocessor, Such as a 68HC11 microproces
`Sor commercially available from Motorola, Inc., known
`Synthesizer circuitry, and known audio logic circuitry. The
`controller 108 controls the operation of the electronic device
`102 according to instructions read from the memory 109.
`The antenna 106 detects and emits the RF signals 105. The
`receiver 107 operates under control of the controller 108 to
`convert Signals received by the antenna 106 into data Signals
`input to the controller 108 for use thereby and into voice
`signals input to the controller 108 for output by the speaker
`110 as audible speech. The transmitter 112 operates under
`control of the controller 108 to convert signals, which
`include data signals generated by the controller 108 and
`voice signals generated by the controller 108 from audible
`Speech input via the microphone 111, for emission by the
`antenna 106.
`The electronic device 102 has a supply terminal (B+) 114,
`battery terminals 115, 116, and 117, a connector 122, and a
`Switch circuit 140. The Supply terminal 114 Supplies power
`to electrical circuitry of the electronic device 102, including
`but not limited to, the receiver 107, the controller 108, and
`transmitter 112 via electrical connections (not shown). The
`battery terminals 115-117 are for electrically connecting to
`the battery 103. Battery terminals 115 and 116 are monitored
`by the controller 108 via lines 118 and 119. Battery terminal
`117 is coupled to an analog ground 120 of the electronic
`device 102.
`The connector 122 is for physically and electrically
`connecting to the accessory 104. The connector 122 has
`multiple pins including information pins 124,125, 127, 128,
`and 129 designated AUD IN, AUD OUT, and R, C, and T
`DATA, respectively; ground pins 126 and 131 designated
`ANL GND and LOG GND; and an external power supply
`pin 130 designated EXT B+. The information pin 124 is
`coupled to the controller 108 via audio in line 132 and an
`identification network 150. The identification network 150 is
`employed to identify the accessory 104. In the illustrated
`embodiment, the identification network 150 includes a resis
`tor 151, having a value of 15 kS2, coupled in series with the
`information pin 124 and the audio in line 132 and a resistor
`152, having a value of 15 kS2, coupled to the audio in line
`132 and the analog ground 120 in a shunt configuration,
`which give the identification network 150 an impedance of
`approximately 30 kS2 looking in from the information pin
`124. The information pin 125 is coupled to the controller 108
`via audio out line 133. The information pins 127-129 are
`coupled to the controller 108 via data lines 134-136. The
`ground pins 126 and 131 are coupled to the analog ground
`
`BACKGROUND OF THE INVENTION
`Electronic devices, Such as cellular telephones, have
`become increasingly popular. Those devices that are com
`patible with a large number of accessories have a commer
`cial advantage. Accessories are used in association with the
`device to increase the functionality thereof. Accessories are
`attached to the device via an accessory connector thereof.
`One Such accessory connector is the Standardized eight pin
`J3-type accessory connector used in MicroTACTM cellular
`telephones manufactured and sold by Motorola, Inc. from
`1989 to the present. The J3-type accessory connector has an
`external power Supply pin; an audio in pin; an audio out pin;
`data pins for high Speed data communications according to
`the three-wire bus protocol used in radiotelephone products
`by Motorola, Inc., and two ground pins in a predetermined
`arrangement.
`To be compatible with the J3-type accessory connector, an
`accessory must have a connector that is designed to mate
`with the accessory connector and have the same number and
`arrangement of pins. To communicate its identity to the
`device, the accessory includes a logic circuit or microcon
`troller capable of driving high Speed data communications
`on the data pins according to the three-wire bus protocol.
`Unfortunately, Such logic circuits or microcontrollers are
`expensive and oftentimes double the cost of the accessory.
`Therefore, what is needed is a low cost apparatus and
`method of identifying an accessory to a device that main
`tains backward compatibility with existing accessories that
`use the accessory connector.
`
`15
`
`25
`
`35
`
`40
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 illustrates, in partial block and partial Schematical
`diagram form, an accessory identification System including
`an electronic device having an accessory identification
`apparatus, a battery, and an accessory; and
`FIG. 2 illustrates, in flow chart form, an accessory iden
`tification method implemented by the electronic device of
`FIG. 1.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS
`An accessory identification apparatus used in an elec
`tronic device includes a connector to couple to an accessory
`and a controller coupled to the connector. The connector
`includes an information pin to receive information generated
`from operation of the accessory. The controller identifies the
`accessory from a Voltage level generated by attachment of
`the accessory to the information pin. In addition, an acces
`Sory identification apparatus used in an accessory includes a
`connector to couple to an electronic device and an identifi
`cation element coupled to the connector. The connector
`includes an information pin to Supply information generated
`from operation of the accessory. The identification element,
`upon attachment of the connector to the electronic device,
`provides an identity of the accessory via the information pin.
`By using the information pin to provide a Voltage level and
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Fundamental Ex 2007-p 4
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`3
`120 and to a logic ground of the controller 108 via line 137,
`respectively. The external power supply pin 130 is coupled
`to the supply terminal 114 via a diode 138. The external
`power Supply pin 130 is monitored by the controller 108 via
`line 139. The connector 122 is preferably the standardized
`eight pin J3-type accessory connector employed by Micro
`TACTM cellular telephones manufactured and sold by
`Motorola, Inc. from 1989 to the present, but may be any
`other Suitable multiple pin accessory connector having an
`external power Supply pin and at least one information pin.
`The Switch circuit 140 selectively connects the battery
`terminal 115 to the Supply terminal 114. The Switch circuit
`140 includes a mechanical Switch 141, a transistor Switch
`142, and a control Switch 143. The mechanical Switch 141
`is coupled to the connector 122, the Supply terminal 114, and
`the battery terminal 115. The mechanical Switch 141 elec
`trically connects the Supply and battery terminals 114 and
`115 when the connector 122 is unattached and opens to
`electrically disconnect the Supply and battery terminals 114
`and 115 when the accessory 104 is physically attached to the
`connector 122.
`The transistor Switch 142 is coupled in parallel with the
`mechanical Switch 141 to prevent interruption of power to
`the electronic device 102 when the mechanical Switch 141 is
`opened or closed. The transistor Switch 142 provides a
`conduction path between the Supply and battery terminals
`114 and 115 until a voltage level at the supply terminal 114
`meets or exceeds a voltage level at the battery terminal 115
`causing the transistor Switch 142 to turn off. The transistor
`switch 142 is preferably a MOSFET (metal-oxide semicon
`ductor field effect transistor) having gate and drain terminals
`coupled to the Supply terminal 114, a Source terminal
`coupled to battery terminal 115, and an intrinsic diode
`coupled across the Source and drain terminals. One skilled in
`the art will recognize that the mechanical Switch 141 in the
`aforementioned arrangement is redundant and the desired
`Switching of the supply and battery terminals 114 and 115
`can be accomplished using only the transistor Switch 142.
`The control switch 143 is coupled to the transistor Switch
`142 and the controller 108 via line 144 to selectively control
`the transistor Switch 142. In response to an enable Signal on
`line 144, the control switch 143 turns on and pulls the gate
`of the transistor Switch 142 low, which in turn forces the
`transistor Switch 142 to turn on and provide a current
`conduction path between the Supply and battery terminals
`114 and 115. The control switch 143 is preferably a BJT
`(bipolar junction transistor) having a collector terminal
`coupled to the gate of the transistor Switch 142, a base
`coupled to the controller 108 via line 144, and an emitter
`coupled to the analog ground 120.
`Although electronic device 102 is illustrated as a cellular
`telephone, the present invention will also find application in
`radios, portable computers, cordleSS telephones, two-way
`radios, pagers, personal digital assistants, tape recorders, and
`the like, and “electronic device' as used herein shall refer to
`all Such battery powered electronic devices and their equiva
`lents.
`The battery 103 includes an electrochemical cell 160, a
`thermistor 161, and contacts 162-164. The electrochemical
`cell 160 includes a positive polarity terminal 165 coupled to
`contact 162 and a negative polarity terminal 166 coupled to
`contact 164. The electrochemical cell 160 is preferably
`rechargeable, and can be, for example, any one of the
`following chemical types: Nickel-Cadmium (NiCd), Nickel
`Metal Hydride (NiMH), Alkaline, or Lithium Ion. In the
`illustrated embodiment, the electrochemical cell 160 Sup
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,859,522
`
`4
`plies a battery voltage supply, preferably of 6 VDC (direct
`current), at the positive polarity terminal 165. The thermistor
`161 is coupled to the contacts 163 and 164. A voltage level
`acroSS the thermistor 161 forms a temperature Signal corre
`sponding to the temperature of the electrochemical cell 160.
`The accessory 104 has a plug 171, a transformer and
`regulator 172, a connector 173, and an identification element
`174. The accessory 104 can be a modem, a hands-free
`adapter, a battery Saver, or the like, and includes accessory
`circuitry 170. The accessory circuitry 170 can include a
`microprocessor or microcontroller requiring a logic ground;
`and data or audio input/output devices Such as a keypad, a
`microphone, or a speaker requiring a connection to an
`analog ground 175 of the accessory 104. However, in the
`illustrated embodiment, the accessory 104 is a mid rate
`charger or fast rate charger that does not include the acces
`sory circuitry 170 and, thus, is low cost.
`The plug 171 is compatible to mate with a conventional
`wall outlet (not shown) and provide external power (e.g.,
`110 V AC (alternating current) supply) to the accessory 104
`from the outlet. Alternatively, the plug 171 could be com
`patible to mate with a cigarette lighter port to provide power
`to the accessory 104 from an automobile electrical System,
`or with another Suitable power Supply.
`The transformer and regulator 172 is coupled to the plug
`171 and has conventional circuitry. The transformer and
`regulator 172 provides an external power Supply to connec
`tor 173 via line 176. In the illustrated embodiment, the
`external power Supply is a current limited constant Voltage
`supply supplying an 8.6 V DC output voltage for both the
`mid and fast rate chargers, a 340 mA current for the mid rate
`charger, and a 850 mA current for the fast rate charger. The
`transformer and regulator 172 preferably includes a tracking
`circuit that adjusts output power according to feedback
`received on line 176. In the event that the accessory 104 has
`the accessory circuitry 170, the transformer and regulator
`172 outputs regulated power on line 177 to power the
`accessory circuitry 170. The transformer and regulator 172
`is coupled to the analog ground 175.
`The connector 173 is for physically and electrically
`connecting to the connector 122 of the electronic device 102.
`The connector 173 has multiple pins including information
`pins 179, 180, 182, 183, and 184 designated AUD OUT,
`AUD IN, and R, C, and T DATA, respectively; ground pins
`181 and 186 designated ANL GND and LOG GND; and an
`external power supply pin 185 designated EXT B+. The
`information pins 179 and 180 are coupled to an audio out
`line 187 and an audio in line 188, respectively. The infor
`mation pins 181-183 are coupled to data lines 190-192. The
`ground pins 181 and 186 are coupled to the analog ground
`175 and logic ground line 193, respectively. The external
`power Supply pin 185 is coupled to the transformer and
`regulator 172 via line 176.
`The identification element 174 is employed to identify the
`accessory 104 to the electronic device 102. The identifica
`tion element 174 has two ends, one end coupled to line 176
`and the other end coupled to the audio out line 187. The
`identification element 174 is uniquely valued in each dif
`ferent type of the accessory 104. In other words, the iden
`tification element 174 is selected to have a different electri
`cal value for each different type of the accessory 104. For
`example, in the illustrated embodiment, the identification
`element 174 employed in the mid rate charger accessory is
`a 120 kS2 resistor, and the identification element 174
`employed in the fast rate charger accessory is a 36 kS2
`resistor.
`
`Fundamental Ex 2007-p 5
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`5,859,522
`
`15
`
`25
`
`35
`
`40
`
`S
`As will be further discussed below, accessory
`identification, in the illustrated embodiment, is primarily
`accomplished, in the electronic device 102, by the controller
`108, the connectors 122, and the identification network 150
`and, in the accessory 104, by the connector 173, the iden
`tification element 174, and the external power Supply pro
`vided by the transformer and regulator 172, which collec
`tively comprise an accessory identification apparatuS 195.
`The accessory identification system 100 operates accord
`ing to an accessory identification method shown in FIG. 2.
`Steps of the method of FIG. 2 are stored in the memory 109
`of FIG. 1 as instructions, which are executed by the con
`troller 108 in the following manner.
`Referring to FIGS. 1 and 2, the controller 108 waits until
`the battery 103 is attached to the electronic device 102 (at
`step 200). The battery 103 is attached to the electronic
`device 102 when the contacts 162-164 of the battery 103 are
`physically mated with, and electrically connected to, the
`battery terminals 115-117, respectively. Upon attachment of
`the battery 103, the positive polarity terminal 165 of the
`electrochemical cell 160 is electrically connected to the
`supply terminal 114 and the electronic device 102 is pow
`ered by the battery voltage supply. The controller 108
`detects attachment of the battery 103 from the presence of
`the battery voltage supply on line 118. The diode 138
`prevents the power supplied by the battery 103 from drain
`ing out the connector 122. The electronic device 102 is
`powered from the battery 103 until it discharges to a voltage
`level that is insufficient to operate electronic device 102.
`Next, the controller 108 waits until the accessory 104 is
`attached to the electronic device 102 (at step 201). The
`accessory 104 is attached to the electronic device 102 when
`the connectors 173 and 122 are physically mated so that the
`pins 179-186 and 124-131, respectively, are held in elec
`trical contact. The mechanical Switch 141 of the Switch
`circuit 140 opens upon physical mating of the connectors
`122 and 173. The transistor Switch 142 of the Switch circuit
`140 turns off when the external power supply is supplied to
`the Supply terminal 114 from the transformer and regulator
`172 via the path of line 176, the pins 185 and 130, and the
`diode 138. The transistor Switch 142 turns off because, in the
`illustrated embodiment, the voltage level of the external
`power Supply at the Supply terminal 114 is approximately
`8.4V after passing through the diode 138, which exceeds the
`battery Supply Voltage of approximately 6 V at the battery
`terminal 115. The controller 108 senses attachment of the
`accessory 104 from the presence of the external power
`supply on line 139. Once the mechanical Switch 141 is open
`and the transistor Switch 142 is off, the electrochemical cell
`160 of the battery 103 is disconnected from the Supply
`terminal 114 and the electronic device 102 is powered by the
`external power Supply of the accessory 104.
`Also upon attachment of the accessory 104, the identifi
`cation element 174 of the accessory 104 is electrically
`connected to the identification network 150 of the electronic
`device 102 via the pins 179 and 124, and the analog grounds
`175 and 120 are intercoupled via pins 181 and 126. The
`external Supply Voltage of the accessory 104, which is
`coupled to the identification element 174 via line 176, drives
`the identification element 174 and the identification network
`150 to generate a voltage level on the audio in line 132 of
`the electronic device 102. In the illustrated embodiment, a
`Voltage level of approximately 1.72 V is generated on the
`audio in line 132 when the mid rate charger accessory is
`attached and a voltage level of approximately 3.91 V is
`generated on the audio in line 132 when the fast rate charger
`accessory is attached. If the accessory 104 has the accessory
`
`45
`
`50
`
`55
`
`60
`
`65
`
`6
`circuitry 170, audio is communicated between the accessory
`circuitry 170 and the controller 108 via the path of audio out
`line 187-pin 179-pin 124-audio in line 132 and the path of
`audio out line 133-pin 125-pin 180-audio in line 188; data
`is communicated between the accessory circuitry 170 and
`the controller 108 via the path of data line 190-pin 181-pin
`127-data line 134, the path of data line 191-pin 182-pin
`128-data line 135, and the path of data line 192-pin 184-pin
`129-data line 136 according to the three-wire bus protocol
`utilized in radiotelephone products manufactured and Sold
`by Motorola, Inc. or other Suitable high Speed data commu
`nication protocol; and the logic grounds are intercoupled via
`lines 193 and 137 and pins 186 and 131.
`Once the accessory 104 is attached, the controller 108
`measures the Voltage level on the audio in line 132 (at Step
`202). Next, the controller 108 compares the voltage level on
`the audio in line 132 to Voltage level ranges Stored in an
`accessory lookup table in the memory 109 (at steps 204 and
`206). The accessory lookup table also contains an accessory
`identity associated with each Voltage level range. In
`particular, the controller 108 determines if the voltage level
`on the audio in line 132 falls within a first voltage level range
`defined by voltage level V1 and voltage level V2, which are
`preferably approximately 1.6 V and approximately 1.9 V,
`respectively (at step 204). If the voltage level on the audio
`in line 132 falls within the first voltage level range, the
`controller 108 identifies the accessory 104 from the acces
`Sory lookup table as a mid rate charger (at Step 208).
`If the voltage level on the audio in line 132 does not fall
`within the first voltage level range, the controller 108
`determines if the voltage level on the audio in line 132 falls
`within a Second Voltage level range defined by Voltage level
`V3 and voltage level V4, approximately 3.6 V and approxi
`mately 4.2 V, respectively (at step 206). If the voltage level
`on the audio in line 132 falls within the second voltage level
`range, the controller 108 identifies the accessory 104 from
`the accessory lookup table as a fast rate charger (at step 210).
`If the voltage level on the audio in line 132 does not fall
`within the second voltage level range, the controller 108
`ends the method (at step 212).
`The accessory lookup table is described above as only
`containing Voltage level ranges and identities associated
`with two accessories. However, one skilled in the art will
`recognize that the accessory lookup table could be made
`larger to contain additional Voltage level ranges and acces
`sory identities, and that the method of FIG. 2 could be easily
`modified Such that the controller 108 continues to traverse
`the larger lookup table following step 206 and prior to
`ending the method at Step 212.
`Next, the controller 108 determines if the voltage and the
`temperature of the battery 103 are within a predetermined
`range for charging the battery 103 at a mid rate (at step 218)
`or a fast rate (at step 220). The controller 108 determines if
`a Voltage level of the battery voltage Supply measured on
`line 118 falls within a Suitable charging Voltage range Stored
`in the memory 109, Such as the Voltage range of approxi
`mately 5.8 V to approximately 7.8 V. The controller 108 also
`determines if a temperature level of the battery 103 indicated
`by the temperature signal measured on line 119 falls within
`a Suitable charging temperature range Stored in the memory
`109, such as the temperature range of approximately 5 C.
`to 40° C.
`If the voltage level and the temperature level fall within
`Suitable ranges, the controller 108 initiates charging of the
`battery 103 at the mid or fast rate by placing an enable signal
`online 144 (at step 214). The enable signal drives the control
`
`Fundamental Ex 2007-p 6
`TCT et al v Fundamental
`IPR2021-00428
`
`

`

`5,859,522
`
`15
`
`7
`Switch 143 to turn on the transistor Switch 142 and conduct
`current Supplied by the external power Supply at the Supply
`terminal 114 to the electrochemical cell 160 of the battery
`103 via the battery terminal 115. The current supplied by the
`external power Supply at the mid or fast rate charges the
`battery 103. The controller 108 maintains the enable signal
`on the line 144 as long as the battery 103 remains within the
`Voltage and temperature range at Step 214 and is determined
`to be not fully charged (at step 218). In the illustrated
`embodiment, the controller 108 determines that the battery
`103 is fully charged when the temperature of the battery 103
`exceeds 45 C. Once the battery 103 is fully charged, the
`controller 108 ends the method (at step 212).
`By using the AUD OUT and IN information pins 179 and
`124 and audio out and in lines 187 and 132 to communicate
`the identity of the accessory 104 to the electronic device
`102, the accessory identification system 100 remains back
`wards compatible with other previous accessories of the
`electronic device 102 that attach to the connector 122. For
`example, attachment of the Original Ultra Saver accessory
`manufactured and sold by Motorola, Inc. as model number
`SLN9739, to the connector 122 generates a 0 V voltage level
`on the audio in line 132 that is not within the voltage level
`ranges of the aforementioned mid and fast rate chargers.
`Also, attachment of the Zero Install Hands-Free Adapter
`25
`accessory manufactured and Sold by Motorola, Inc. as model
`number SLN3595, to the connector 122 generates an 8 V
`voltage level on the audio in line 132 that is not within the
`Voltage level ranges of the aforementioned mid and fast rate
`charger accessories.
`Use of the identification element 174 and the identifica
`tion network 150 to identify the accessory 104 to the
`electronic device 102 is not limited to those accessories that
`do not output/receive audio to/from the electronic device
`102 (i.e., the mid and fast rate chargers described above).
`For example, a hands-free accessory, which continually
`Supplies microphone audio signals for the electronic device
`102 via the path of audio out line 187-pin 179-pin
`124-audio in line 132, could employ, for example, a 11.2 kS2
`resistor as the identification element 174. The 11.2 kS2
`resistor in conjunction with the identification network 150
`having the 30 kS2 impedance generates a Voltage level of
`approximately 5.7 V at the audio in line 132. The micro
`phone audio signals generated by the hands-free accessory
`during operation thereof are modulated on the Voltage level
`at the audio in line 132. The controller 108 filters the
`modulated Signal to extract the audio Signals for use by the
`electronic device 102 and the voltage level for use in
`identifying the accessory 104. AS Such, the Voltage level on
`the audio in line 132 generated by the identification element
`174 and the identification network 150 from the connection
`of the audio pins 179 and 124 does not interfere with audio
`Signals generated and output by the accessory 104 during
`operation thereof.
`Although shown to be connected to the AUD OUT
`information pin 179 and the AUD IN information pin 124,
`55
`one skilled in the art will recognize that the identification
`element 174 and the identification network 150,
`respectively, could alternatively be connected to R DATA
`information pins 181 and 127, CDATA information pins 182
`and 128, or T DATA information pins 183 and 129,
`respectively, to facilitate identification of the accessory 104
`to the controller 108.
`Thus, it can be seen that an improved accessory identi
`fication apparatus and method can be implemented that
`achieves identification by reusing an information pin of a
`connector, previously used only to receive information gen
`erated from operation of the accessory. Accessory identifi
`cation can be easily accomplished by coupling a low cost
`
`35
`
`8
`resistor network to the audio in pin of the connector of an
`electronic device and coupling a Single low cost resistor to
`an audio out pin of a mating connector of the accessory and
`an external power Supply of the accessory. When the con
`nectors are mated, the external power Supply drives the
`resistor and resistor network to generate a Voltage level from
`which the identity of the accessory can be determined. The
`resistors are Selected to provide a unique electrical Signature
`for each type of accessory and arranged to prevent interfer
`ence with audio generated from operation of the accessory
`and Supplied to the electronic device. AS Such, accessory
`identification can be achieved in a cost effective manner
`without modification of the accessory connector, thereby
`maintaining backwards compatibility with existing accesso
`ries that use the accessory connector.
`What is claimed is:
`1. An accessory identification apparatus for use by an
`electronic device, the apparatus comprising:
`a connector to couple to an accessory, the connector
`including an information pin designated to receive
`information generated from operation of the accessory,
`and wherein the information pin is an audio in pin; and
`a controller coupled to the connector, the controller to
`identify the accessory from a Voltage level generated by
`attachment of the accessory to the information pin.
`2. An accessory identification apparatus according to
`claim 1 wherein the connector further comprises an audio
`out pin, an external power Supply pin, a ground pin, and at
`least one data pin.
`3. An electronic device comprising:
`a connector to couple to an accessory, the connector
`having an audio in pin designated to receive audio
`generated from operation of the accessory;
`an identification network coupled to the audio in pin, the
`identification network having a predetermined imped
`ance, and
`a controller coupled to the identification network, the
`controller, upon attachment of the accessory to the
`connector, to identify the accessory from a Voltage
`level generated by the identification network and the
`audio in pin.
`4. An ac