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[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 1 - 1. gen e ral description the AK7451 is a magnetic rotational angle sensor ic of si monolithic with a built - in hall element, and easily achieve a non - contact rotation angle sensor in combination with diametrically magnetized two pole magnet . by detecting the magnetic field parallel vec tor to the ic package surface, the AK7451 outputs the absolute angular position of the magnet, and the relative angular position. by transverse magnetic field detection method using a magnetic flux concentrator, the AK7451 has e xcellent axial misalignment immunity . AK7451 is the zero latency rotation angle sensor to follow up to 20,000rpm with t he architecture of the tracking servo system, it is suitable to various motor drive applications and an encoder applications. 2. features monolithic integrated 360 degrees angle sensor ic containing h all element. easy to make a contactless rotation sensor with diametrically magnetized two pole magnet. interfaces : spi (a bsolute a ngle ), abz phase output (i ncremental i nterface ) , uvw phase outpu t 12bit angle resolution less than 0.6 deg . angle accuracy at 25 oc maximum tracking speed : 333 rps ( 20,000 rpm ) angle output delay time: 1.8 s operating ambient temperature: - 40 to 125oc various abnormal detection ; abnormal magnetic flux density range etc. various setting functions ; angle zero point, rotation direction, abz resolution / hysteresis etc. zero latency angle sensor ic ak 7451
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 2 - 3. table of contents 1. general description ................................ ................................ ................................ ............................ 1 2. features ................................ ................................ ................................ ................................ .............. 1 3. table of conten ts ................................ ................................ ................................ ................................ 2 4. block diagram and functions ................................ ................................ ................................ ............. 3 5. pin configurations and functions ................................ ................................ ................................ ....... 5 6. absolute maximum ratings ................................ ................................ ................................ ................ 6 7. recommended operating conditions ................................ ................................ ................................ . 6 8. eeprom characteristics ................................ ................................ ................................ .................... 6 9. electrical and magnetic characteristics ................................ ................................ .............................. 7 10. serial interface characteristics ................................ ................................ ................................ ........... 8 11. digital output characteristics ................................ ................................ ................................ ........... 10 12. instructions ................................ ................................ ................................ ................................ ......... 11 13. mode transition diagram and conditions ................................ ................................ ........................ 12 14. serial interface ................................ ................................ ................................ ................................ .. 13 15. regi ster / eeprom address map / configration ................................ ................................ .......... 15 16. abz output figure ................................ ................................ ................................ ............................ 26 17. uvw output figure ................................ ................................ ................................ ........................... 27 18. ab normal detection functions ................................ ................................ ................................ .......... 28 19. angle zero position at shipment, and relation between magnet angle position and output ...... 29 20. package information ................................ ................................ ................................ ......................... 30 20.1. outline dimensions ................................ ................................ ................................ ..................... 30 20.2 . marking ................................ ................................ ................................ ................................ ... 31 important notice ................................ ................................ ................................ ................................ ....... 32
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 3 - 4. b lock diagram and functions f igure 1 . functional block diagram of AK7451 cs he _x type 2 tracking loop encoder logic sclk mosi a b z vdd vss serial if (spi) miso error osc adc _x adc _y he - drive v & i reference esd r egulate _ dig p or fault detect o r pra_y p ra_x arvdd v pra_ swap eeprom dmode testa d6 v x v u v w x _ chop y_ chop pra_ swap regulate _ana drvdd v atpge he _x he _y he _y
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 4 - table 1 . description of circuit block circuit block function he - x/y si monolithic hall e lements. these detect x/y - composition s of flux which are parallel to the ic package surface by using the magnetic concentrator and converts to an electrical signal. x_chop, y_chop s witch its direction of drive current in order to lower offset and noise for the h all element s . he drive d rive h all element s by constant current . pra_x,pra_y a mplify signal s f rom h all element s . pra_swap r educe mismatch of each amplifier gain and hall element current. adc _x
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 5 - 5. pin configurations and functions figure 2 . pin assignment of AK7451 table 2 . pin configuration and functions of AK7451 no. pin name i/o type description 1 a o digital a - phase pulse signal 2 b o digital b - phase pulse signal 3 z o digital z - phase pulse signal 4 u o digital u - phase pulse signal 5 v o digital v - phase pulse signal 6 w o digital w - phase pulse signal 7 error o digital error output pin 8 vdd - power power supply pin 9 vss - gnd ground pin 10 testa i/o analog test dedicated pin . this pin should be non - connection . 11 dmode i digital test dedicated pin . this pin should be non - connection . 12 atpge i digital test dedicated pin . this pin should be non - connection . 13 miso o digital spi output data signal 14 mosi i digital spi input data signal 15 sclk i digital spi clock signal 16 cs i digital spi chip select signal
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 6 - 6. absolute maximum ratings table 3 . absolute maximum ratings parameter symbol min. max. units notes power supply voltage v dda - 0.3 6.5 v vdd pin voltage o n output pin v out - 0.3 v dda v miso,error,a,b,z, u,v,w pin output current on output pin 1 i out1 - 1.25 1.25 ma miso pin output current on output pin 2 i out 2 - 10 10 ma error,a,b,z,u,v,w pin input pin voltage v in - 0.3 v dda + 0.3 ( Q stg - 50 +150 oc warning : stress beyond these listed values may cause permanent damage to the device. even it may not cause damage on the device; it may affect its reliability and longevity. normal operation is not guaranteed. each voltage is with respect to vss pin . 7. recommended operating conditions table 4 . o perating conditions parameter symbol min. typ. max. units notes power supp l y voltage und er o perating c onditions v dd 4.5 5 5.5 v vdd pin operating ambient temperature ta - 40 - +1 25 o c warning: ex ceeding the o peration conditions , the electric and magnetic characteristics are not guaranteed. voltage is with respect to vss pin. 8. eeprom characteristic s table 5 . eeprom characteristics condition s : v dd =4.5 to 5.5v parameter symbol min. typ. max. units notes endurance to rewriting w f 1000 cycle ambient temperature in writing t mem 0 85 oc writing time w t 5 ms
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 7 - 9. electrical and magnetic characteristics table 6 . electrical and magnetic c haracteristic s condition s unless otherwise specified : ta= - 40 to 1 25 o c , v dd =4.5 to 5.5v parameter symbol conditions min. typ. max. unit magnetic flux density range b range 30 50 70 mt angle detection range a range 0 3 5 d eg. angle resolution a res 12bit 0.088 d eg. angle linearity error ( note 1 ) a inl at 25 o drift operating t emperature range ( w ith reference to 25 o hys at 25 o noise at 50mt - 2 2 lsb angle tracking ability f samp 20000 rpm angle output delay time ( note 2 ) t d a t abz hysteresis configuration =invalid ( note 3 ) t sto 25 30 ms supply current i sup no output load 12.7 15.7 ma note 1 . if abz resolution configuration is set to other than exponentiation of 2, the father angle linearity error is added to the specified value in 0 to 1lsb ( 0 to 0.088degree ) . note 2 . this value is in case that abz hysteresis configuration is set to invalid . this value is dependent on abz hysteresis configuration. whenever the setting value is increased, the angle output delay time value increases by 0.5 s at a time. note 3 . it is the time from power - on to becoming high on error pin through judging magnetic flux range error and tracking error. this time is including the circuit setup time, the tracking angle time, the self - d iagnosis of error time. this parameter is not tested at mass production . figure 3 . waveform of vdd and error pin at start - up time 4.5v v dd power on time t sto error pin
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 8 - 10. serial interface characteristics table 7 . serial i/f dc characteristics conditions : ta= - 40 to 1 25 o c , v dd =4.5 to 5.5v parameter symbol pin conditions min. typ. max. unit input high level v hsi cs,sclk, mosi 0.7v dd v input low level v lsi cs,sclk, mosi 0.3 v dd v input current i si cs,sclk, mosi - 10 +10 a output current i so miso - 1 1 ma output high level v hso miso i so = 1ma (source) 0.8v dd v output low level v lso miso i so = 1ma (sink) - 0.3 0.2 v dd v output load capacity c so miso 100 pf table 8 . serial i/f ac characteristics conditions : ta= - 40 to 1 25 o c , v dd =4.5 to 5.5v parameter symbol min typ. max unit notes time from fall of cs to st art of c l k t1 100 ns necessary time from end of sc l k to rise of cs t2 100 ns set - up time of input data t3 70 ns hold time of input data t4 70 ns time to fix output data t5 150 ns time from rise of cs to hi - z of miso t6 0 500 ns transition time from 0. 2 v dd to 0. 8 v dd of output data t7 100 ns transition time from 0. 8 v dd to 0. 2 v dd of output data t8 100 ns sclk high time t9 200 ns sclk low time t10 200 ns sclk ris e time (note 4 ) t11 30 ns s clk fall time (note 4 ) t12 30 ns id le time in writing register t13 2.5 s id le time in writing eeprom t13 5 ms sclk frequency - 0.001 2000 khz note 4 . these parameters are not tested at mass production.
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 9 - figure 4. ac timing of serial i/f
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 10 - 11. digital output characteristics table 9 . digital output dc characteristics condition s :ta= - 40 to 1 25 o c , v dd =4.5 to 5.5v parameter symbol pin note s min typ. max unit output current i d o a,b,z , u,v,w, error - 2 2 ma output low level v l d o a,b,z, u,v,w, error i d o =2ma(sink) - 0.3 0.2v dd v output high level v hd o a,b,z, u,v,w, error i d o =2ma(source) 0.8 v dd v output load capacity c d o a,b,z, u,v,w, error 100 pf table 10 . digital output ac characteristics condition s :ta= - 40 to 125 o c , v dd =4.5 to 5.5v parameter symbol pin note s min typ. max unit rise time t rd o a,b,z, u,v,w, error c d o = 100pf, i d o =2ma(source) time f r o m 0.2 v dd to 0.8 v dd 150 ns fall time t fd o a,b,z, u,v,w, error c d o = 100pf, i d o =2ma(sink) time fro m 0. 8 v dd to 0.2 v dd 150 ns
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 11 - 12. instructions the AK7451 s function is described in this section. the function is roughly divided into programing procedure (for various setup) and an angle measurement procedure. the operation procedure is as follows. < programing procedure > 1. the AK7451 will start as normal mode after power on automatically. 2. transfer to user mode and write configuration parameters in eeprom and then verify the data. 3. transfer to normal mode and then the AK7451 will output the angle data based on programed parameter. 1. transfer to normal mode . 2. input the r ea d angle command as opcode 1001 via spi, when the absolute angle data is needed. if relative angle data is needed, count the abz output pulses. the abz pulses and uvw pulses are output ted right after startup along with magnet rotating .
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 12 - 13. mode transition diagram and conditions this ic has the following two modes and starts with normal mode at start up. in the normal mode , this sensor will be operated as angle output mode. user can read the angle data via spi pin and abz pin and also can transfer to user mode by using specific opcode. and also in this mode, uvw output is available to detect the magnet rotor position in bcdl motor driving. in the user mode , the user can set the various operation conditions via spi communication. the settable item will be described later in this section. note 5 . in user mode, output on error pin is low state (abnormal status). a nd the accuracy of magnetic flux density measurement is not gu a ran teed. each mode can be changed by writing specific opcode and specific data on specific address as the diagram below. figure 5. mode transition diagram mode name note normal mode in this mode, the absolute angle data including error bit, parity bit and mode information will be outputted via spi communication by inputting specific opcode. and the abz and uvw pulses are output t ed automatically along with magnet rotating. user mode d o not use the angle data (abz and uvw pulses) in this mode. the following functions are available in this mode. a. magnetic flux density measurement b. a bnormal state checking c. m emory lock d. angle zero position setting e. abz output enable/disable and resolution, hys teresis setting f. abnormal detection enable/disable setting g. rotation direction setting h. uvw output enable/disable and the number of output pulses, hysteresis setting addr. 0x02 opcode 0 101 data 0x50f normal mode user mode addr. 0x02 opcode 0 101 data 0 or re power - on
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 13 - 14. serial interface when register/memory setting or absolute angle measurement is needed, use spi communication. the serial communication protocol and each register/memory description are described in this section. data format 1) write memory/register in user mode 2) read memory register in user mode 3) read angle data in normal mode figure 6 . timing chart of serial i/f note 6 . figure symbols are as following; ox : operation code ax : memory/register address md: mode information md is 0 in normal mode, and 1 in user mode dx : data p1 : parity bit for angle data[11:6] p2 : parity bit for angle data[5:0] e : error bit ( normal = 1,abnormal = 0 ) * : dont care. cs scl 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 mosi o3 o1 o0 a6 a5 a4 a3 d7 d6 d5 miso hi-z 17 18 19 20 21 22 23 24 d9 d8 a2 a1 a0 * * * o2 d10 d11 d4 d3 d2 d1 d0 cs scl 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 mosi o3 o2 o1 o0 a6 a5 a4 a3 miso 17 18 19 20 21 22 23 24 a2 a1 a0 d7 d6 d5 d4 d3 d2 d1 d0 d11 d9 d8 hi-z hi-z * * d10 cs scl mosi miso hi-z hi-z p1 p2 e d5 d4 d3 d2 d1 d0 d11 d10 d9 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 * * o2 o1 o0 o3 d8 d7 d6 md
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 14 - note 7 . parity bit is odd parity in normal and even parity in abnormal. and the abz hysteresis configuration which is described later in this section i s reflected in read angle data. note 8 . send data and receive data are from msb to lsb in sequence. table 1 1 . opcode specification opcode[3 0] opcode name note 0000 n.a. 0001 write eeprom able to write a data on eeprom. 0010 read eeprom able to read an eeprom. 0011 write register able to write a data on register. 0100 read register able to read a register. 0101 change mode able to change between normal mode and user mode. transition conditions are described in
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 15 - 15. register / eeprom address map / configration register address map table 1 2 . register address map addr. [hex] re g ister symbol r/w permission note normal mode user mode 0x00 r_ ang r r 12bit a ngle data 0x01 r_ mag n.a. r magnetic f lux d ensity s trength roughly 1lsb/mt 0x02 r_ chmd w r/w for m ode state 0x03 r_ errmon n.a. r error monitor ( this register will show what kind of error is. ) 0x04 - n.a. n.a. 0x05 - n.a. n.a. 0x06 r_ zp n.a. r/w for set up a ngle z ero p oint 0x07 r_ rdabz n.a. r/w for set up rotation direction , z phase output form , abz output enable/disable , abz hysteresis and abz resolution . 0x08 r_ mlk n.a. r for m emory l ock 0x09 r_ ebdis n.a. r/w for set up a bnormal d etection d isable 0x0a r_ uvw n.a. r/w for set up uvw output enable/disable , uvw hysteresis and uvw resolution . note 9 . n.a. = not available, r = read only, r/w = read and write note 1 0 . address 0x02 is only able to be changed by writing opcode 0101 each register configurations ? r_ ang register ( register address :0x00 ) register function : this register contains an output angle data. the angle data consists with the following angle position. and the abz hysteresis configuration which is described later in this section is reflected in this register s value . angle position [] r_ang[11:0] 0 0x000 r_ ang d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_ang[11:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 16 - ? r_ mag register ( register address :0x01 ) register function : this register contains a m agnetic f lux d ensity s trength d ata. the m agnetic f lux d ensity s trength d ata consists with the following m agnetic f lux d ensity s trength . magnetic flux density strength [mt] r_mag[6:0] 0 0x00 1 0x01 2 0x02 3 0x03 127 0x7f note 1 1 . this magnetic flux density measurement data s accuracy which is stored in this register is not guaranteed, it is recommended to use for only reference . ? r_ chmd register ( register address 0x02 ) register function : this register is to configure the m ode (normal mode/user mode). this register can be written by using opcode [ 0101]. each mode configuration is the following. mode r_chmd [11:0] default normal mode 0x000 ? r_ errmon register ( register address 0x03 ) register f unction : this register shows the error state. corresponding bit data is 0 in the abnormal s tate. relation between the a bnormal state and bit data is the following. abnormal state bit data value in abnormal state value in normal state magnetic flux density strength abnormity r_errmon [1] 0 1 tracking lost r_ errmon [0] 0 1 r_mag d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_mag [6:0] r_chmd d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_chmd [ 11 :0] r_errmon d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_errmon [1:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 17 - ? r_ zp register ( register address 0x06 ) re g ister f unction : this register is available for setting arbitrarily a ngle position as zero position . relation between the a ngle p osition and the zp d ata is the following. the register value is duplicated from corresponding memory after power on or, when the mode t ransferred to "normal mode" from user mode . zero point angle position [] r_ zp [11:0] default 0 0x000 note 1 2 . a setup of this register is reflected in abz and uvw output. ? r_ rdabz register ( register address 0x07 ) re g ister f unction : this register is used for configuring rotation direction , z phase output form , abz output enabling / disabling , abz phase hysteresis and abz resolution . the register value is duplicated from corresponding memory after power on or, when the mode transferred to "normal mode" from user mode . a) rotation direction configuration: the output direction can be set in if the angle data i ncreases clockwise or clockwise (refer to section 16). relation between th e rotation direction and rd is as following. rotation direction r_ rd default ccw (+) 0x0 b) z phase output form configuration: the z phase can be set as either among two mod es . one is a normal z phase output which carries out toggle at 0 degree position. the other is a switch output which keeps low state in more than 180 degree and high state in less than 180 degree. (refer to section 14.3 abz output figure ) z phase output for m r_ z_mode default normal output 0x0 c) abz output enable configuration: it is possible to disable the abz output as necessary . when the abz output is set to inability (0x0) , the output becomes hi - z. abz output state r_ abz_e default abz output inability r_zp d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_zp[11:0] r_rdabz d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_rd r_z_mode r_abz_e r_abz_hys[2:0] r_abz_res[3:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 18 - d) abz h ysteresis configuration: this configuration can be used to prevent unexpected abz pulses under noise influence. relation between abz hysteresis and abz_hys set value is as following. abz hysteresis r_ abz_hys[ 2 : 0 ] default invalid 0x0 0lsb 0x1 1lsb 0x2, 0x5, 0x6, 0x7 figure 7. operational overview of hysteresis configuration note 1 3 . as to the difference of abz hysteresis between 0lsb and invalid; internal angle data always alternates between two adjacent angle data because of the tracking loop characteristics even if the environment is a static condition. in invalid configuration, abz output is reflected by internal angle data directly. but in 0lsb configuration, abz output is reflected by internal angle data when internal angle data change over two consecutive lsb in same rotation direction. thus in this case, lsb bit alternation caused by noise is masked fr om abz output.
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 19 - e) abz output resolution configuration: able to configure the abz resolution. relation between abz resolution and set value is as following. abz phase resolution r_ abz_res[d3:0] default 1024ppr 0x0 ? r_ mlk register ( register address 0x08 ) re g ister f unction : this register is to be duplicated from data at the memory lock configuration address on eeprom. this address is read - only for confirming the memory lock state. relation between the memory lock state and mlk register value is as following. memory lock state r_ mlk[1:0] default unlocked 0x3 ? r_ ebdis register ( register address : 0x09 ) register function : this register is used for disabling / enabling each abnormal diagnosis function as necessary. relation between the diagnosis function and ebdis is as following. each bit have its function, and 1 means disable. the register value is duplicated from corresponding memory after power on or, w hen the mode transferred to "normal mode" from u s er mode . abnormal diagnosis parameter bit data default magnetic flux density r_ ebdis [ 1 ] 0 tracking lost r_ebdis [ 0] 0 r_mlk d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_mlk[1:0] r_ebdis d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_ebdis[1:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 20 - ? r_ uvw register ( register address : 0x0 a) register function : this register is used for configuring uvw output enabling / disabling , uvw phase hysteresis , the number of uvw pulses per a rotation . the register value is duplicated from corresponding memory after power on or, when the mode transferred to "normal mode" from user mode . a) uvw output enable configuration: it is possible to disa ble the uvw output as necessary . when the abz output is set t o inability (0x0) , the output becomes hi - z. uvw output state r_ uvw_e default uvw output inability (hi - z output) 0x0 uvw output 0x1 b) uvw h ysteresis configuration: this configuration can b e used to prevent unexpected uvw pulses under noise influence. relation between uvw hysteresis and uvw _hys set value is as following. uvw hysteresis r_ uvw_hys[ 2 : 0 ] default invalid 0x0 0lsb 0x1 1lsb 0x2, 0x5, 0x6, 0x7 c) the number of uvw pulses configuration: it is possible to set the number of uvw pulse s per a rotation by changing following bits according to the number of dcbl motor rotor s magnetic poles. the number of uvw pulses r_ uvw_res [ 2 : 0 ] default 1ppr 0x0 2ppr 0x1 3ppr 0x2 r_uvw d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content r_uvw_e r_uvw_hys[2:0] r_uvw_res[2:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 21 - eeprom address map table 1 3 . eeprom memory address map note 1 4 . once set m emory l ock, this ic cannot be written to any memory. note 1 5 . each register value is duplicated from corresponding memory when the mode transferred to "normal mode" or re - power on. in order to reflect a setup data on an output, please re turn to a normal mode or re - power on. each memory configurations ? e_ id 1 memory ( memory address 0x04 ) memory function : this memory can be written as identification information or the lot information by the ic user . default value is 0x00 0. ? e_ id2 memory ( memory address 0x05 ) memory f unction : this memory can be written as identification information or the lot information by the ic user . default value is 0x00 0. addr.[hex] memory symbol r/w permission note normal mode user mode 0x00 - n.a. n.a. 0x01 - n.a. n.a. 0x02 - n.a. n.a. 0x03 - n.a. n.a. 0x04 e_ id1 n.a. r/w for id data 0x05 e_ id2 n.a. r/w for id data 0x06 e_ zp n.a. r/w for to set up angle zero point. 0x07 e_ rdabz n.a. r/w for set up rotation direction , z phase output form , abz output enable/disable , abz hysteresis and abz resolution . 0x08 e_ mlk n.a. r/w for memory lock 0x09 e_ ebdis n.a. r/w for set up a bnormal detection disable 0x0a e_ uvw n.a. r/w for set up uvw output enable/disable , uvw hysteresis and uvw resolution . e_id1 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_id1[11:0] e_id2 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_id2[11:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 22 - ? e_ zp memory ( memory address 0x06 ) memory f unction : this memory is available for setting arbitrarily a ngle position as zero position . relation between the a ngle p osition and the zp d ata is the following. zero point angle position [] e_ zp [11:0] default 0 0x000 note 16 . a setup of this register and memory is reflected in abz and uvw output. ? e_ rdabz memory ( memory address 0x07 ) memory f unction : this register is used for configuring rotation direction , z phase output form , abz output enabling / disabling , abz phase hysteresis and abz resolution . relation between each bit and setting value is as following. a) rotation direction configuratio n: the output direction can be set in if the angle data i ncreases clockwise or clockwise (refer to section 16). relation between th e rotation direction and rd is as following. rotation direction e_ rd default ccw (+) 0x0 b) z phase output form configuration: the z phase can be set as either among two mod es one is a normal z phase output which carries out toggle at 0 degree position. the other is a switch output which keeps low state in more than 180 degree and high state in less than 180 degree. (refer to section 14.3) z phase output form e_ z_mode default normal output 0x0 c) abz output enable configuration: it is possible to disable the abz output as necessary . when the abz output is set to inability (0x0) , the output becomes hi - z. abz output state e_ abz_e default abz output inability e_zp d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_zp[11:0] e_rdabz d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_rd e_z_mode e_abz_e e_abz_hys[2:0] e_abz_res[3:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 23 - d) abz h ysteresis configuration: this configuration can be used to prevent unexpected abz pulses under noise influence. relation between abz hysteresis and abz_hys set value is as following. abz hysteresis e_ abz_hys[ 2 : 0 ] default invalid 0x0 0lsb 0x1 1lsb 0x2, 0x5, 0x6, 0x7 note 1 7 . as to the difference of abz hysteresis between 0lsb and invalid; internal angle data always alternates between two adjacent angle data because of the tracking loop characteristics even if the environment is a static c ondition. in invalid configuration, abz output is reflected by internal angle data directly. but in 0lsb configuration, abz output is reflected by internal angle data when internal angle data change over two consecutive lsb in same rotation direc tion. thus in this case, lsb bit alternation caused by noise is masked from abz output.
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 24 - e) abz output resolution configuration: able to configure the abz resolution by using this configuration . relation between abz resolution and set value is as following. abz phase resolution abz_res [ 3 : 0 ] default 1024ppr 0x0 ? e_ mlk memory (memory address 0x08) memory function : this configuration is used for locking the memory. by writing data [0x00] (except for 0x03) in address [0x08], the memory lock is executed. once the memory is locked, all memory data cannot be changed, and also the memory lock function cannot be released. memory lock state e_ mlk[1:0] default unlocked 0x3 ? e_ ebdis memory ( memory address : 0x09 ) memory function : this memory is used for disabling / enabling each abnormal diagnosis function as necessary. relation between the diagnosis function and ebdis is as following. by writing 1 in a corresponding bit, the abnormal diagnosis function is disabled. abnormal diagnosis parameter bit data default magnetic flux density e_ebdis [ 1 ] 0 tracking lost e_ ebdis [ 0] 0 e_mlk d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_mlk[1:0] e_ebdis d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_ebdis[1:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 25 - ? e_ uvw memory ( memory address : 0x0 a) memory function : this memory is used for configuring uvw output enabling / disabling , uvw phase hysteresis , the number of uvw pulses per a rotation . relation between each bit and setting value is as following. a) uvw output enable configuration: it is possible to disa ble the uvw o utput as necessary . when the abz output is set to inability (0x0) , the output becomes hi - z. uvw output state e_ uvw_e default uvw output inability (hi - z output) 0x0 uvw output 0x1 b) uvw h ysteresis configuration: this configuration can b e used to prevent unexpected uvw pulses under noise influence. relation between uvw hysteresis and uvw _hys set value is as following. uvw hysteresis e_ uvw_hys[ 2 : 0 ] default invalid 0x0 0lsb 0x1 1lsb 0x2, 0x5, 0x6, 0x7 c) the number of uvw pulses configuration: it is possible to set the number of uvw pulse s per a rotation by changing following bits according to the number of dcbl motor rotor s magnetic poles. the number of uvw pulses e_ uvw_res [ 2 : 0 ] default 1ppr 0x0 2ppr 0x1 3ppr 0x2 e_uvw d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 content e_uvw_e e_uvw_hys[2:0] e_uvw_res[2:0]
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 26 - 16. abz output figure the abz output is following figure; the a and b are 1024pulses and z pulse is outputted with one pulse during a rotation. ( the number of a and b pulse is settable via spi. ) . moreover, the z phase can be set to normal output which toggle at 0 degree position and switch output which keeps low state in more than 180 degree and high state in less than 180 degree. figure 9 . abz output figure note 2 8 . z - phase output corresponds to the zero point configuration which should be set by user. the abz output is generated by the bit operation from 12 bit absolute angle data. in order to generate the abz output, the angle data ang[11:0] is once changed into ang_abz[11:0] by the following operation. ang_abz[11:0] = absolute angle data ang[11:0] (abz resolution set value ab z_res[ppr] 4 ) 4096 then, from obtained ang_abz[11:0], the a phase is generated by bit1 , and b phase is generated by bit1 ? bit0 . z phase is generated by nor all 12bit data. note 19 . when the abz output is except a exponentiation setup of 2, the a ngle l inearity e rror deteriorates in range of - 1 to 0 lsb( - 0.088 to 0 degree.). z phase normal output selection z phase switch output selection b a z 360 (4096 code) 180 (2048 code) b a z 360
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 27 - 17. uvw output figure this is a function which outputs the uvw signal which is needed for a dcbl motor drive. the uvw output can be set in the range of 1 - 8 pulses to one rotation. moreover, u, v and w signal has 120 degree phase difference in an electric angle respectively. the zero point setup is reflected to start position of uvw. regarding the zero point setup, see the zp register/memory setup in section 14. figure 10 . uvw output figure if there is difference between uvw and abz hysteresis, the start position of uvw phase shifts by the difference of uvw and abz hysteresis setup. in order to generate the uvw output, the angle data ang[11 :0] is once changed into ang_uvw[5 :0] by the following operation. ang_uvw[5:0] = absolute angle data ang[11:0] ( the number of uvw pulse set value uvw _res[ppr] 6 ) 4096 by using obtained ang_uvw[5:0], each u, v and w phase signal is generated as following. u : when ang_uvw [5:0] value is from 6n to 6n+2, an output is high - level, and it is a low level when other. v : when ang_uvw [5:0] value is from 6n+2 to 6n+4, an output is high - level, and it is a low level when other. w : when ang_uvw [5:0] value is from 6n+1 to 6n+3, an output is low - level, and it is a high level when other. here, n means the ord er of output pulses. (from 0 to the number of pulses - 1). in case of 1 pulse setup in case of 2 pulse setup 0 ? ? ? ? ? ? ? ? ? ? ? ? ? ?
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 28 - 18. abnormal detection functions this ic detects an abnormal state and indicates an abnormal state via error pin and serial interface. abnormal state is outputted at the angle output timing after 2.7ms (typ) delay after detecting abnormal state. 1) abnormal detection items magnetic flux density range error when ic is applied in less than 10mt (typ) , the abnormal state is detected. tracking lost if the angle error in the tracking by the type 2 servo is greater than or equal to 2 , it will be tracking lost state (if the lock state is out due to type 2 servo). because it is not overlooking the accurate absolute angle output in this state, it will be the anomaly detection state. also monitoring of the abnormal state is every 2.56ms (typ). 2) output state in abnormal the output is as following during abnormal state. ? abz and uvw output abz and uvw signal is outputted even if during abnormal state but the data may not be correct. ? spi output the parity bits(p1 and p2 bit) and error bit is outputted as following. p1 bit p2 bit e bit normal state odd parity odd parity 1 abnormal state even parity even parity 0 ? error pin output output is low in abnormal state (high in normal state). the updating cycle of error pin output is every 80 s(typ.). note 2 0 . when the abnormal state is released, ic returns to the normal output state automatically. note 2 1 . in user mode, output on error pin is low state.
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 29 - 19. angle zero position at shipment, and relation between magnet angle position and output the relation between magnet angle position over the package and angle output data is as following in configuration at shipment (zero point configuration: default). the relation between the angle output of the following figure, a pac kage, and a magnet posi tion has a few degree error. when the relation between an angle output and a magnet position correctly has to be decided, use a zero point setup. figure 1 1 . relationship of magnet position and the angle output at factory default setting relation between angle position and serial angle data relation between angle pos ition and serial angle data is as following. when the zero point is configured , the zero point is the angle position 0 . angle position [] angle data 0 0x000 ( 3604096 ) 1 0x001 ( 3604096 ) 2 0x002 ( 3604096 ) 3 0x003 : : ( 3604096 ) 4095 0xfff s 0 n 90 n s
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 30 - 20. package information 20.1. outline dimensions figure 1 2 . package outline drawing sensor position information figure 1 3 . sensor position sensor area accuracy top view sectional view sensor area accuracy sensor area ? sensor 0 . 2 m m ` ` 0 . 5 5 0 . 1 ` `
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 31 - 20.2. marking production information is printed on the package surface by laser marking. figure1 4 . marking information product name year (last digit) yy ww x x x production control code week production control code pin #1 indication AK7451 AK7451 1637eau production control code
[ ak 7451 ] 01600 6 637 - e - 00 201 6 / 05 - 32 - important notice 0. asahi kasei microdevices corporation (akm) reserves the right to make changes to the information contained in this document without notice. when you consider any use or application of akm product stipulated in this document (product), please make inquiries the sales office of akm or authorized distributors as to current status of the products. 1. all information included in this document are provided only to illustra te the operation and application examples of akm products. akm neither makes warranties or representations with respect to the accuracy or completeness of the information contained in this document nor grants any license to any intellectual property rights or any other rights of akm or any third party with respect to the information in this document. you are fully responsible for use of such information contained in this document in your product design or applications. akm assumes no liability for any losse s incurred by you or third parties arising from the use of such information in your product design or applications. 2. the product is neither intended nor warranted for use in equipment or systems that require extraordinarily high levels of quality and/or reliability and/or a malfunction or failure of which may cause loss of human life, bodily injury, serious property damage or serious public impact, including but not limited to, equipment used in nuclear facilities, equipment used in the aerospace industr y, medical equipment, equipment used for automobiles, trains, ships and other transportation, traffic signaling equipment, equipment used to control combustions or explosions, safety devices, elevators and escalators, devices related to electric power, and equipment used in finance - related fields. do not use product for the above use unless specifically agreed by akm in writing. 3. though akm works continually to improve the products quality and reliability, you are responsible for complying with safety st andards and for providing adequate designs and safeguards for your hardware, software and systems which minimize risk and avoid situations in which a malfunction or failure of the product could cause loss of human life, bodily injury or damage to property, including data loss or corruption. 4. do not use or otherwise make available the product or related technology or any information contained in this document for any military purposes, including without limitation, for the design, development, use, stockpiling or manufacturing of nuclear, chemical, or biological weapons or missile technology products (mass destruction weapons). when exporting the products or related technology or any information contained in this document, you should comply with the applicable export control laws and regulations and follow the procedures required by such laws and regulations. the products and related technology may not be used for or incorporated into any products or systems whose manufacture, use, or sale is prohibit ed under any applicable domestic or foreign laws or regulations. 5. please contact akm sales representative for details as to environmental matters such as the rohs compatibility of the product. please use the product in compliance with all applicable laws and regulations that regulate the inclusion or use of controlled substances, including without limitation, the eu rohs directive. akm assumes no liability for damages or losses occurring as a result of noncompliance with applicable laws and regulations. 6 . resale of the product with provisions different from the statement and/or technical features set forth in this document shall immediately void any warranty granted by akm for the product and shall not create or extend in any manner whatsoever, any liabil ity of akm. 7. this document may not be reproduced or duplicated, in any form, in whole or in part, without prior written consent of akm.

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