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  fully accurate 14-/16-bit v out nanodac ? spi interface 2.7 v to 5.5 v, in an sot-23 ad5040/ad5060 rev. a information furnished by analog devices is believed to be accurate and reliable. however, no responsibility is assumed by analog devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. specifications subject to change without notice. no license is granted by implication or otherwise under any patent or patent rights of analog devices. trademarks and registered trademarks are the property of their respective owners. one technology way, p.o. box 9106, norwood, ma 02062-9106, u.s.a. tel: 781.329.4700 www.analog.com fax: 781.461.3113 ? 2005-2010 analog devices, inc. all rights reserved. features single 14-/16-bit dac, 1 lsb inl power-on reset to midscale or zero scale guaranteed monotonic by design 3 power-down functions low power serial interface with schmitt-triggered inputs small 8-lead sot-23 package, low power fast settling time of 4 s typically 2.7 v to 5.5 v power supply low glitch on power-up sync interrupt facility applications process control data acquisition systems portable battery-powered instruments digital gain and offset adjustment programmable voltage and current sources programmable attenuators general description the ad5040 and the ad5060, members of the adi nano dac family, are low power, single 14-/16-bit buffered voltage-out dacs that operate from a single 2.7 v to 5.5 v supply. the ad5040/ad5060 parts offer a relative accuracy specification of 1 lsb and operation are guaranteed monotonic with a 1 lsb dnl specification. the parts use a versatile 3-wire serial interface that operates at clock rates up to 30 mhz and is compatible with standard spi?, qspi?, microwire?, and dsp interface standards. the reference for both the ad5040 and ad5060 is supplied from an external v ref pin. a reference buffer is also provided on-chip. the ad5060 incorporates a power-on reset circuit that ensures the dac output powers up to midscale or zero scale and remains there until a valid write takes place to the device. the ad5040 and the ad5060 both contain a power-down feature that reduces the current con- sumption of the device to typically 330 na at 5 v and provides software-selectable output loads while in power-down mode. the parts are put into power-down mode over the serial interface. total unadjusted error for the parts is <2 mv. both parts exhibit very low glitch on power-up. functional block diagram ad5040/ ad5060 v dd v out v ref power-on reset dac register dac input control logic power-down control logic resistor network ref(+) sclk din 04767-001 sync dacgnd buf agnd output buffer figure 1. product highlights 1. available in a small, 8-lead sot-23 package. 2. 14-/16-bit accurate, 1 lsb inl. 3. low glitch on power-up. 4. high speed serial interface with clock speeds up to 30 mhz. 5. three power-down modes available to the user. 6. reset to known output voltage (midscale, zero scale). table 1. related devices part no. description ad5061 2.7 v to 5.5 v, 16-bit nano dac d/a, 4 lsb inl, sot-23 ad5062 2.7 v to 5.5 v, 16-bit nano dac d/a,1 lsb inl, sot-23 ad5063 2.7 v to 5.5 v, 16-bit nano dac d/a, 1 lsb inl, msop
ad5040/ad5060 rev. a | page 2 of 24 table of contents features .............................................................................................. 1 ? applications ....................................................................................... 1 ? general description ......................................................................... 1 ? functional block diagram .............................................................. 1 ? product highlights ........................................................................... 1 ? revision history ............................................................................... 2 ? specifications ..................................................................................... 3 ? timing characteristics ..................................................................... 5 ? absolute maximum ratings ............................................................ 6 ? esd caution .................................................................................. 6 ? pin configuration and function descriptions ............................. 7 ? typical performance characteristics ............................................. 8 ? terminology .................................................................................... 14 ? theory of operation ...................................................................... 15 ? dac architecture ....................................................................... 15 ? reference buffer ......................................................................... 15 ? serial interface ............................................................................ 15 ? power-on reset ........................................................................... 16 ? software reset ............................................................................. 16 ? power-down modes .................................................................. 17 ? microprocessor interfacing ....................................................... 17 ? applications ..................................................................................... 19 ? choosing a reference for the ad5040/ ad5060 ................... 19 ? bipolar operation using the ad5040/ ad5060 .................... 19 ? using the ad5040/ad5060 with a galvanically isolated interface chip ............................................................................. 20 ? power supply bypassing and grounding ................................ 20 ? outline dimensions ....................................................................... 21 ? ordering guide .......................................................................... 21 ? revision history 1/10rev. 0 to rev. a changes to table 2, relative accuracy (inl) and endnote 1 .... 3 updated outline dimensions ....................................................... 21 changes to ordering guide .......................................................... 21 10/05revision 0: initial version
ad5040/ad5060 rev. a | page 3 of 24 specifications v dd = 5.5 v, v ref = 4.096 v @ r l = unloaded, c l = unloaded; t min to t max , unless otherwise noted. table 2. a, b, and y grades 1 parameter min typ max unit test conditions/comments static performance resolution 16 bits ad5060 14 bits ad5040 relative accuracy (inl) 2 0.5 2 lsb ?40c to +85c, ad5040/ad5060 a grade 0.5 1 lsb ?40c to +85c, ad5040/ad5060 b grade 0.5 1.5 ?40c to +125c, ad5060 y grade total unadjusted error (tue) 2 0.1 2.0 mv ?40c to +85c, ad5040/ad5060 0.1 2.0 ?40c to +125c, ad5060 y grade differential nonlinearity (dnl) 2 0.5 1 lsb guaranteed monotonic, ?40c to +85c, ad5040/ad5060 0.5 1 guaranteed monotonic, ?40c to +125c, y grade gain error 0.01 0.02 % of fsr t a = ?40c to +85c, ad5040/ad5060 0.01 0.03 t a = ?40c to +125c ad5060 y grade gain error temperature coefficient 1 ppm of fsr/c offset error 0.02 1.5 mv t a = ?40c to + 85c, ad5040/ad5060 0.02 2.0 t a = ?40c to + 125c, ad5060 y grade offset error temperature coefficient 0.5 v/c full-scale error 0.05 2.0 mv all 1s loaded to dac register, ad5040 ad5060; t a = ?40c to +85c 0.05 2.0 all 1s loaded to dac register, t a = ?40c to +125c, ad5060 y grade output characteristics 3 output voltage range 0 v ref v output voltage settling time 4 s ? scale to ? scale code transition to 1 lsb, r l = 5 k output noise spectral density 64 nv/ hz dac code = midscale, 1 khz output voltage noise 6 v p-p dac code = midscale , 0.1 hz to 10 hz bandwidth digital-to-analog glitch impulse 2 nv-s 1 lsb change around code 57386, r l = 5 k, c l = 200 pf digital feedthrough 0. 003 nv-s dac code = full scale dc output impedance (normal) 0. 015 output impedance tolerance 10% dc output impedance (power-down) (output connected to 1 k network) 4 1 k output impedance tolerance 400 (output connected to 100 k network) 100 k output impedance tolerance 20 k capacitive load stability 1 nf loads used r l = 5 k, r l = 100 k, r l = slew rate 1. 2 v/s ? scale to ? scale code transition to 1 lsb, r l = 5 k, c l = 200 pf short-circuit current 60 ma dac code = full scale, output shorted to gnd, t a = 25c 45 dac code = zero scale, output shorted to v dd , t a = 25c dac power-up time 4.5 s time to exit power-down mode to normal mode of ad5060, 24 th clock edge to 90% of dac final value, output unloaded dc power supply rejection ratio ?92.11 db v dd 10%, dac code = full scale
ad5040/ad5060 rev. a | page 4 of 24 a, b, and y grades 1 parameter min typ max unit test conditions/comments wideband spurious-free dynamic range (sfdr) ?67 db output frequency = 10 khz reference input/output v ref input range 5 2 v dd ? 50 mv input current (power-down) 0.1 a zero scale loaded input current (normal) 0.5 a dc input impedance 1 m logic inputs input current 6 1 2 a v il , input low voltage 0.8 v v dd = 4.5 v to 5.5 v 0.8 v dd = 2.7 v to 3.6 v v ih , input high voltage 2.0 v v dd = 2.7 v to 5.5 v 1.8 v dd = 2.7 v to 3.6 v pin capacitance 4 pf power requirements v dd 2.7 5.5 v all digital inputs at 0 v or v dd i dd (normal mode) dac active and excluding load current v dd = 2.7 v to 5.5 v 1.0 0. 82 1.2 1. 0 ma v in = v dd and v il = gnd, v dd = 5.0 v, v ref = 4.096 v, code = midscale v in = v dd and v il = gnd, v dd = 3.0 v, v ref = 2.7 v, code = midscale i dd (all power-down modes) v dd = 2.5 v to 5.5 v 0.33 1 a v ih = v dd and v il = gnd, v dd = 5.5 v, v ref = 4.096 v, code = midscale 0.065 v ih = v dd and v il = gnd, v dd = 3.0 v, v ref = 4.096 v, code = midscale 1 temperature range for the a and b grades is ?40c to + 85 c, typical at 25c; temperature range for the y grade is ?40c to + 125c. 2 linearity calculated using a reduce d code range (160 to code 65535 for ad 5060 ) and (40 to code 16383 for ad5040). 3 guaranteed by design and characterization, not production tested. 4 1 k power-down network not available with the ad5040. 5 the typical output supply headroom performance for various reference voltages at ?40c can be seen in figure 26. 6 total current flowing into all pins.
ad5040/ad5060 rev. a | page 5 of 24 timing characteristics v dd = 2.7 v to 5.5 v; all specifications t min to t max , unless otherwise noted. table 3. parameter limit 1 unit test conditions/comments t 1 2 33 ns min sclk cycle time t 2 5 ns min sclk high time t 3 3 ns min sclk low time t 4 10 ns min sync to sclk falling edge setup time t 5 3 ns min data setup time t 6 2 ns min data hold time t 7 0 ns min sclk falling edge to sync rising edge t 8 12 ns min minimum sync high time t 9 9 ns min sync rising edge to next sclk fall ignore 1 all input signals are specified with tr = tf = 1 ns/v (10% to 90% of v dd ) and timed from a voltage level of (v il + v ih )/2. 2 maximum sclk frequency is 30 mhz. t 4 t 3 t 2 t 5 t 7 t 6 d0 d1 d2 d22 d23 sync sclk 04767-002 t 9 t 1 t 8 d23 d22 din figure 2. ad5060 timing diagram
ad5040/ad5060 rev. a | page 6 of 24 absolute maximum ratings table 4. parameter rating v dd to gnd ?0.3 v to +7.0 v digital input voltage to gnd ?0.3 v to v dd + 0.3 v v out to gnd ?0.3 v to v dd + 0.3 v v ref to gnd ?0.3 v to v dd + 0.3 v operating temperature range industrial (a, b grade) ?40c to +85c extended automotive temperature range (y grade) ?40c to +125c storage temperature range ?65c to +150c maximum junction temperature 150c sot-23 package power dissipation (t j max ? t a )/ ja ja thermal impedance 206c/w jc thermal impedance 91c/w reflow soldering (pb-free) peak temperature 260c time-at-peak temperature 10 sec to 40 sec esd (ad5040/ad5060) 1. 5 kv stresses above those listed under absolute maximum ratings may cause permanent damage to the device. this is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. this device is a high performance integrated circuit with an esd rating of <2 kv. it is esd sensitive. proper precautions should be taken for handling and assembly. esd caution esd (electrostatic discharge) sensitive device. electros tatic charges as high as 4000 v readily accumulate on the human body and test equipment and can discharge wi thout detection. although this product features proprietary esd protection circuitry, permanent dama ge may occur on devices subjected to high energy electrostatic discharges. therefore, proper esd precautions are recommended to avoid performance degradation or loss of functionality.
ad5040/ad5060 rev. a | page 7 of 24 pin configuration and fu nction descriptions ad5040/ ad5060 top view (not to scale) v out sync 18 agnd sclk 27 din dacgnd 36 04767-003 v ref 45 v dd figure 3. pin configuration table 5. pin function descriptions pin no. mnemonic description 1 din serial data input. these parts have a 16-/24-bit shift register . data is clocked into the register on the falling edge of the serial clock input. 2 v dd power supply input. these parts can be operated from 2.7 v to 5.5 v and v dd should be decoupled to gnd. 3 v ref reference voltage input. 4 v out analog output voltage from dac. 5 agnd ground reference point for analog circuitry. 6 dacgnd ground input to the dac core. 7 sync level-triggered control input (active low). this is the frame synchronization signal for the input data. when sync goes low, it enables the input shift register and data is transferred in on the falling edges of the following clocks. the dac is updated following the 16th/24th clock cycle unless sync is taken high before this edge, in which case the rising edge of sync acts as an interrupt, and the write sequence is ignored by the dac. 8 sclk serial clock input. data is clocked into the input shift register on the falling ed ge of the serial clock input. data can be transferred at rates up to 30 mhz.
ad5040/ad5060 rev. a | page 8 of 24 typical performance characteristics 1.6 ?1.6 ?1.4 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 160 10160 30160 50160 60160 20160 40160 04767-040 inl error (lsb) dac code v dd = 5.5v v ref = 4.096v t a = 25 c 0.6 ?0.6 ?0.5 ?0.4 ?0.3 ?0.2 ?0.1 0.1 0 0.2 0.3 0.4 0.5 160 2260 8560 12760 14860 4360 6460 10660 04767-061 inl error (lsb) dac code v dd = 5.5v v ref = 4.096v t a = 25 c figure 4. typical ad5060 inl plot figure 7. typical ad5040 inl plot 1.6 ?1.6 ?1.4 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 160 10160 30160 50160 60160 20160 40160 04767-039 dnl error (lsb) dac code v dd = 5.5v v ref = 4.096v t a = 25 c 0.40 ?0.40 ?0.35 ?0.30 ?0.25 ?0.20 ?0.15 ?0.10 ?0.05 0 0.05 0.10 0.15 0.20 0.25 0.30 0.35 160 2260 6460 10660 12760 14860 4360 8560 04767-060 dnl error (lsb) dac code v dd = 5.5v v ref = 4.096v t a = 25 c figure 8. typical ad5040 dnl plot figure 5. typical ad5060 dnl plot 0.020 ?0.020 ?0.015 ?0.010 ?0.005 0 0.005 0.010 0.015 160 2260 8560 12760 14860 16960 4360 6460 10660 04767-062 tue error (mv) dac code v dd = 5.5v v ref = 4.096v t a = 25 c 0.10 ?0.10 ?0.08 ?0.06 ?0.04 ?0.02 0 0.02 0.04 0.06 0.08 160 10160 30160 50160 60160 20160 40160 04767-041 tue error (mv) dac code v dd = 5.5v v ref = 4.096v t a = 25 c figure 9. typical ad5040 tue plot figure 6. typical ad5060 tue plot
ad5040/ad5060 rev. a | page 9 of 24 04767-009 2.0 ?1.6 ?1.4 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 5.5 5.0 4.5 4.0 3.5 3.0 2.5 inl error (lsb) reference voltage (v) max inl error @ v dd = 5.5v min inl error @ v dd = 5.5v t a = 25 c figure 10. inl vs. reference input voltage 1 04767-010 2.0 ?1.6 ?1.4 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 5.5 5.0 4.5 4.0 3.5 3.0 2.5 dnl error (lsb) reference voltage (v) max dnl error @ v dd = 5.5v min dnl error @ v dd = 5.5v t a = 25 c figure 11. dnl vs. reference input voltage 1 04767-011 2.0 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 5.5 5.0 4.5 4.0 3.5 3.0 2.5 tue error (mv) reference voltage (v) max tue error @ v dd = 5.5v min tue error @ v dd = 5.5v t a = 25 c figure 12. tue vs. reference input voltage 1 1.8 ?1.8 ?1.6 ?1.4 ?1.2 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 ?40 140 120100806040200 ?20 04767-067 offset error (mv) temperature (c) max offset error @ v dd = 5.5v max offset error @ v dd = 2.7v min offset error @ v dd = 2.7v v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v min offset error @ v dd = 5.5v figure 13. typical offset error vs. temperature 1 0.5 ?0.5 ?0.4 ?0.3 ?0.2 ?0.1 0 0.1 0.2 0.3 0.4 ?40 140 120 100806040200 ?20 04767-066 gain error (% fsr) temperature (c) v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v max gain error @ v dd = 5.5v max gain error @ v dd = 2.7v min gain error @ v dd = 5.5v min gain error @ v dd = 2.7v figure 14. typical gain error vs. temperature 1 1.4 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 1.0 1.2 ?40 140 120100806040200 ?20 04767-069 inl error (lsb) temperature (c) v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v max inl error @ v dd = 5.5v max inl error @ v dd = 2.7v min inl error @ v dd = 2.7v min inl error @ v dd = 5.5v figure 15. typical inl error vs. temperature 1 1 ad5060 only.
ad5040/ad5060 rev. a | page 10 of 24 1.0 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 ?40 140 120100806040200 ?20 04767-071 dnl error (lsb) temperature (c) v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v max dnl error @ v dd = 5.5v max dnl error @ v dd = 2.7v min dnl error @ v dd = 2.7v min dnl error @ v dd = 5.5v figure 16. typical dnl error vs. temperature 1 max tue error @ v dd = 5.5v max tue error @ v dd = 2.7v min tue error @ v dd = 2.7v min tue error @ v dd = 5.5v 1.0 ?1.0 ?0.8 ?0.6 ?0.4 ?0.2 0 0.2 0.4 0.6 0.8 ?40 140 120100806040200 ?20 04767-068 tue error (mv) temperature (c) v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v figure 17. typical tue error vs. temperature 1 1.4 0 0.2 0.4 0.6 0.8 1.0 1.2 ?40 140 120100806040200 ?20 04767-072 i dd (ma) temperature (c) v dd = 5.5v, v ref = 4.096v v dd = 2.7v, v ref = 2.0v max i dd @ v dd = 5.5v max i dd @ v dd = 2.7v figure 18. typical supply current vs. temperature 1 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0 5m 10m 15m 20m 25m 30m 35m 40m 45m 04767-044 i dd (ma) frequency (hz) v dd = 5.5v v ref = 4.096v t a = 25 c full-scale three quarter scale quarter-scale mid-scale zero-scale figure 19. typical supply current vs. frequency @ 5.5 v 1 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 0 5m 10m 15m 20m 25m 30m 35m 40m 45m 04767-045 i dd (ma) v dd = 3v v ref = 2.5v t a = 25 c 1.6 frequency (hz) full-scale three quarter scale quarter-scale mid-scale zero-scale figure 20. typical supply current vs. frequency @ 3 v 1 04767-015 2.5 0 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 6.0 5.5 5.0 4.5 4.0 3.5 3.0 i dd ( a) supply voltage (v) v ref = 2.5v t a = 25 c code = midscale figure 21. typical supply current vs. supply voltage 1 1 ad5060 only.
ad5040/ad5060 rev. a | page 11 of 24 04767-014 0 0 3.00 2.75 2.50 2.25 2.00 1.75 1.50 1.25 1.00 0.75 0.50 0.25 70000 60000 50000 40000 30000 20000 10000 i dd (ma) dac code v dd = 3.0v, v ref = 2.5v v dd = 5.5v, v ref = 4.096v t a = 25 c figure 22. typical supply cu rrent vs. digital input code 1 04767-017 ch2 50mv/div ch1 2v/div time base 400ns/div 24th clock falling ch1 = sclk ch2 = v out figure 23. ad5060 digital-to-analog glitch impulse (see figure 24 ) 0.117 0.101 0.102 0.103 0.104 0.105 0.106 0.107 0.108 0.109 0.111 0.110 0.112 0.113 0.114 0.115 0.116 0 25 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400 425 450 475 500 525 04767-043 amplitude samples v dd = 5v v ref = 4.096v r = 5k c = 220pf code = 57386 figure 24. ad5060 digital-to-analog glitch energy 1 ad5060 only. 04767-020 v dd = 3v dac = full scale v ref = 2.7v t a = 25c y axis = 2 v/div x axis = 4s/div figure 25. 0.1 hz to 10 hz noise plot 04767-091 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 0 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 5.55.3 headroom (v) reference voltage (v) figure 26. v dd headroom vs. reference voltage 5.05 5.00 4.95 4.90 4.85 4.80 4.75 4.70 4.65 4.60 4.55 4.70 4.72 4.74 4.76 4.78 4.80 4.82 4.84 4.86 4.88 4.90 4.92 4.94 4.96 4.98 5.00 04767-042 dac output voltage (v) v ref (v) v dd = 5.0v t a = 25 c dac = full-scale figure 27. output voltage vs. reference voltage
ad5040/ad5060 rev. a | page 12 of 24 5.005 4.975 4.980 4.985 4.990 4.995 5.000 5.50 5.005.055.105.155.205.255.305.355.405.45 04767-065 dac output (v) v dd (v) v ref = 5v t a = 25c figure 28. typical output vs. supply voltage 04767-019 ch2 2v/div ch1 2v/div time base = 5.00 s ch3 2v ch3 = sclk ch2 = v out ch1 = trigger figure 29. time to exit power-down to midscale ?50 100 1k 10k 100k 1m 04767-046 noise spectral density (nv/ hz) v dd = 5v v ref = 4.096v t a = 25 c 400 350 300 250 200 150 100 50 0 frequency (hz) quarter-scale zero-scale full-scale mid-scale figure 30. noise spectral density 04767-047 ch4 50.0mv m4.00 s ch1 1.64v c4 = 143mv p-p 1k to gnd zero-scale figure 31. glitch upon entering software power-down to zero scale 04767-048 ch4 20.0mv m1.00 s ch1 1.64v c4 = 50mv p-p 1k to gnd zero-scale figure 32. glitch upon exiting software power-down to zero scale 04767-049 ch3 2.00v ch2 50mv m1.00ms ch3 1.36v 2 c2 25mv p-p c3 4.96v p-p c3 fall 935.0 s c3 rise s no valid edge 3 t t figure 33. glitch upon entering hardware power-down to three-state
ad5040/ad5060 rev. a | page 13 of 24 04767-050 ch3 2.00v ch2 50mv m1.00ms ch3 1.36v 2 c2 30mv p-p c3 4.96v p-p c3 fall s no valid edge c3 rise 946.2 s 3 t t 2.1 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 ?10 s 9.96 s 8 s6 s4 s2 s0 ?2 s ?4 s ?6 s ?8 s 04767-052 v dd = 5.5v v ref = 4.096v 10% to 90% rise time = 0.688 s slew rate = 1.16v/ s dac output 1.04v 2.04v figure 34. glitch upon exiting hardware power-down to zero scale figure 37. typical output slew rate 0.0010 0.0008 0.0006 0.0004 0.0002 0 ?0.0002 ?0.0004 ?0.0006 ?0.0008 ?25 ?20 ?15 ?10 ?5 0 5 10 15 20 25 30 04767-051 voltage (v) current (ma) code = mid-scale v dd = 5v, v ref = 4.096v v dd = 3v, v ref = 2.5v v dd = 5.5v v dd = 3v 16 14 0 2 4 6 8 10 12 0.83 more 0.91 0.90 0.89 0.88 0.87 0.86 0.85 0.84 04767-075 frequency bin figure 35. typical output load regulation figure 38. i dd histogram v dd = 3.0 v 0.10 ?0.10 ?0.08 ?0.06 ?0.04 ?0.02 0 0.02 0.04 0.06 0.08 ?25 ?20 ?15 ?10 ?5 0 5 10 15 20 25 30 04767-063 v out (v) i out (ma) code = midscale v dd = 5v, v ref = 4.096v v dd = 3v, v ref = 2.5v v dd = 3v, v ref = 2.5v v dd = 5v, v ref = 4.096v 14 0 2 4 6 8 10 12 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11more 04767-076 frequency bin figure 36. typical current limiting plot figure 39. i dd histogram v dd = 5.0 v
ad5040/ad5060 rev. a | page 14 of 24 terminology relative accuracy for the dac, relative accuracy or integral nonlinearity (inl) is a measure of the maximum deviation, in lsbs, from a straight line passing through the endpoints of the dac transfer function. a typical ad5060 inl vs. code plot is shown in figure 4 . differential nonlinearity (dnl) differential nonlinearity is the difference between the measured change and the ideal 1 lsb change between any two adjacent codes. a specified differential nonlinearity of 1 lsb maximum ensures monotonicity. this dac is guaranteed monotonic by design. a typical ad5060 dnl vs. code plot is shown in figure 5 . offset error offset error is a measure of the output error when zero code (0x0000) is loaded to the dac register. ideally, the output should be 0 v. the zero-code error is always positive in the ad5040/ad5060 because the output of the dac cannot go below 0 v. this is due to a combination of the offset errors in the dac and output amplifier. zero-code error is expressed in mv. full-scale error full-scale error is a measure of the output error when full-scale code (0xffff ad5060, 0x3fff ad5040) is loaded to the dac register. ideally, the output should be v dd ? 1 lsb. full-scale error is expressed in percent of full-scale range. gain error this is a measure of the span error of the dac. it is the devia- tion in slope of the dac transfer characteristic from ideal, expressed as a percent of the full-scale range. tot a l un a dju s te d e r ror ( t u e ) total unadjusted error is a measure of the output error taking all the various errors into account. a typical ad5060 tue vs. code plot is shown in figure 6 . offset error drift this is a measure of the change in zero-code error with a change in temperature. it is expressed in v/c. gain error drift this is a measure of the change in gain error with changes in temperature. it is expressed in (ppm of full-scale range)/c. digital-to-analog glitch impulse digital-to-analog glitch impulse is the impulse injected into the analog output when the input code in the dac register changes state. it is normally specified as the area of the glitch in nv-s and is measured when the digital input code is changed by 1 lsb at the worst case code 53786; see figure 23 and figure 24 . the expanded view in figure 23 shows the glitch generated following completion of the calibration routine; figure 24 zooms in on this glitch. digital feedthrough digital feedthrough is a measure of the impulse injected into the analog output of the dac from the digital inputs of the dac, but is measured when the dac output is not updated. it is specified in nv-s and measured with a full-scale code change on the data busthat is, from all 0s to all 1s, and vice versa.
ad5040/ad5060 rev. a | page 15 of 24 theory of operation the ad5040/ad5060 are single 14-/16-bit, serial input, voltage output dacs. the parts operate from supply voltages of 2.7 v to 5.5 v. data is written to the ad5060 in a 24-bit word format, and to the ad5040 in a 16-bit word format, via a 3-wire serial interface. both the ad5040 and ad5060 incorporate a power-on reset circuit that ensures the dac output powers up to a known out- put state (midscale or zero-scale, see the ordering guide ). the devices also have a software power-down mode that reduces the typical current consumption to less than 1 a. dac architecture the dac architecture of the ad5060 consists of two matched dac sections. a simplified circuit diagram is shown in figure 40 . the 4 msbs of the 16-bit data-word are decoded to drive 15 switches, e1 to e15. each of these switches connects 1 of 15 matched resistors to either dacgnd or the v ref buffer output. the remaining 12 bits of the data-word drive switches s0 to s11 of a 12-bit voltage mode r-2r ladder network. 2r 04767-027 s0 v ref 2r s1 2r s11 2r e1 2r e2 2r e15 2r v out 12-bit r-2r ladder four msbs decoded into 15 equal segments figure 40. ad5060 dac ladder structure reference buffer the ad5040 andad5060 operate with an external reference. the reference input (v ref ) has an input range of 2 v to v dd ? 50 mv. this input voltage is then used to provide a buffered reference for the dac core. serial interface the ad5060/ad5040 have a 3-wire serial interface ( sync , sclk, and din), which is compatible with spi, qspi, and microwire interface standards, as well as most dsps. shows a timing diagram of a typical ad5060 write sequence. figure 2 the write sequence begins by bringing the sync line low. for the ad5060, data from the din line is clocked into the 24-bit shift register on the falling edge of sclk. the serial clock frequency can be as high as 30 mhz, making these parts compatible with high speed dsps. on the 24th falling clock edge, the last data bit is clocked in and the programmed function is executed (that is, a change in the dac output or a change in the mode of operation). at this stage, the sync line can be kept low or be brought high. in either case, it must be brought high for a minimum of 12 ns before the next write sequence so that a falling edge of sync can initiate the next write sequence. because the sync buffer draws more current when v ih = 1.8 v than it does when v ih = 0.8 v, sync should be idled low between write sequences for an even lower power operation of the part. as previously indicated, however, it must be brought high again just before the next write sequence. the ad5040 requires 16 clock periods to update the input shift register. on the 16th falling clock edge, the last data bit is clocked in and the programmed function is executed (that is, a change in the dac output or a change in the mode of operation). input shift register the ad5060 input shift register is 24 bits wide; see figure 41 . pd1 and pd0 are control bits that control the operating mode of the partnormal mode or any one of three power-down modes (see the power-down modes section for more detail). the next 16 bits are the data bits. these are transferred to the dac register on the 24th falling edge of sclk. data bits db15 (msb) db0 (lsb) d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 normal operation 1k to gnd 100k to gnd 3-state power-down modes 0 0 1 1 0 1 0 1 04767-028 0 0 0 0 0 0 pd1 pd0 figure 41. ad5060 input register content
ad5040/ad5060 rev. a | page 16 of 24 the ad5040 input shift register is 16 bits wide; see figure 42 . pd1 and pd0 are control bits that control the operating mode of the partnormal mode or any one of two power-down modes (see power-down modes section for more detail). the next 14 bits are the data bits. these are transferred to the dac register on the 16th falling edge of sclk. sync interrupt in a normal write sequence for the ad5060, the sync line is kept low for at least 24 falling edges of sclk, and the dac is updated on the 24th falling edge. however, if sync is brought high before the 24th falling edge, the write sequence is interrupted. the shift register is reset and the write sequence is considered invalid. neither an update of the dac register contents nor a change in the operating mode occurs; see . in a normal write sequence for the ad5040, the figure 43 sync line is kept low for at least 16 falling edges of sclk, and the dac is updated on the 16th falling edge. however, if sync is brought high before the 16th falling edge, the write sequence is interrupted. the shift register is reset and the write sequence is considered invalid. neither an update of the dac register contents nor a change in the operating mode occurs. power-on reset the ad5040 and ad5060 both contain a power-on reset circuit that controls the output voltage during power-up. the dac register is filled with the zero-scale code or midscale code and the output voltage is set to zero scale or midscale (see the ordering guide for more details on the reset model). it remains there until a valid write sequence is made to the dac. this is useful in applications where it is important to know the output state of the dac while it is in the process of powering up. software reset the ad5060 device can be put into software reset by setting all bits in the dac register to 1; this includes writing 1s to bit d23 and bit d16, which is not the normal mode of operation. for the ad5040 this includes writing 1s to bit d15 and bit d14, which is also not the normal mode of operation. note that the sync interrupt command cannot be performed if a software reset command is started in the ad5040 or ad5060. 04767-074 data bits db13 (msb) db0 (lsb) d13pd0pd1 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 normal operation 100k to gnd 3-state power-down modes 0 0 1 0 1 0 figure 42. ad5040 input register content 04767-031 db23 db23 db0 db0 invalid write sequence: sync high before 24 th falling edge valid write sequence, output updates on the 24 th falling edge sync sclk din figure 43. ad5060 sync interrupt facility
ad5040/ad5060 rev. a | page 17 of 24 power-down modes the ad5060 features four operating modes, and the ad5040 features three operating modes. these modes are software pro- grammable by setting two bits in the control register (bit db17 and bit db16 in the ad5060 and bit db15 and bit db14 in the ad5040). table 6 and table 7 show how the state of the bits corresponds to the operating mode of the two devices. table 6. operating modes for the ad5060 db17 db16 operating mode 0 0 normal operation power-down modes: 0 1 3-state 1 0 100 k to gnd 1 1 1 k to gnd table 7. operating modes for the ad5040 db15 db14 operating mode 0 0 normal operation power-down modes: 0 1 3-state 1 0 100 k to gnd 1 1 see software reset section in both the ad5060 and the ad5040, when the two most significant bits are set to 0, the part has normal power consumption. however, for the three power-down modes of the ad5060 and the two power down modes of the ad5040, the supply current falls to less than 1a at 5 v (65 na at 3 v). not only does the supply current fall, but the output stage is also internally switched from the output of the amplifier to a resistor network of known values. this is advantageous because the output impedance of the part is known while the part is in power-down mode. the output is connected internally to gnd through a 1 k resistor (ad5060 only) or a 100 k resistor, or it is left open-circuited (three-stated). the output stage is illustrated in figure 44 . power-down circuitry ad5040/ ad5060 dac 04767-029 v out resistor network output buffer figure 44. output stage during power-down the bias generator, the dac core, and other associated linear circuitry are all shut down when power-down mode is activated. however, the contents of the dac register are unaffected when in power-down. the time to exit power-down is typically 2.5 s for v dd = 5 v, and 5 s for v dd = 3 v; see figure 29 . microprocessor interfacing ad5040/ad5060 to adsp-2101/adsp-2103 interface figure 45 shows a serial interface between the ad5040/ad5060 and the adsp-2101/adsp-2103. the adsp-2101/adsp-2103 should be set up to operate in the sport transmit alternate framing mode. the adsp-2101/adsp-2103 sport is pro- grammed through the sport control register and should be configured for internal clock operation, active low framing, and 16-bit word length. transmission is initiated by writing a word to the tx register after the sport has been enabled. ad5040/ ad5060 1 1 additional pins omitted for clarity tfs dt sclk sync din sclk 04767-030 adsp-2101/ adsp-2103 1 figure 45. ad5040/ad5060 to adsp-2101/adsp-2103 interface ad5040/ad5060 to 68hc11/68l11 interface figure 46 shows a serial interface between the ad5040/ ad5060 and the 68hc11/68l11 microcontroller. sck of the 68hc11/68l11 drives the sclk pin of the ad5040/ad5060, while the mosi output drives the serial data line of the dac. the sync signal is derived from a port line (pc7). the setup conditions for correct operation of this interface require that the 68hc11/68l11 be configured so that its cpol bit is 0 and its cpha bit is 1. when data is being transmitted to the dac, the sync line is taken low (pc7). when the 68hc11/68l11 is configured where its cpol bit is 0 and its cpha bit is 1, data appearing on the mosi output is valid on the falling edge of sck. serial data from the 68hc11/68l11 is transmitted in 8-bit bytes with only 8 falling clock edges occurring in the transmit cycle. data is transmitted msb first. in order to load data to the ad5040/ad5060, pc7 is left low after the first eight bits are transferred, and a second serial write operation is performed to the dac. pc7 is taken high at the end of this procedure. ad5040/ ad5060 1 1 additional pins omitted for clarity pc7 sck mosi sync sclk din 04767-032 68hc11/ 68l11 1 figure 46. ad5040/ad5060 to 68hc11/68l11 interface
ad5040/ad5060 rev. a | page 18 of 24 ad5040/ad5060 to microwire interface ad5040/ad5060 to blackfin? adsp-bf53x interface figure 49 shows an interface between the ad5040/ad5060 and any microwire-compatible device. serial data is shifted out on the falling edge of the serial clock and is clocked into the ad5040/ad5060 on the rising edge of the sk. figure 47 shows a serial interface between the ad5040/ ad5060 and the blackfin adsp-53x microprocessor. the adsp-bf53x processor family incorporates two dual-channel synchronous serial ports, sport1 and sport0, for serial and multiprocessor communications. using sport0 to connect to the ad5040/ad5060, the setup for the interface is: dt0pri drives the sdin pin of the ad5040/ad5060, while tsclk0 drives the sclk of the part; the sync is driven from tfs0. microwire 1 1 additional pins omitted for clarity cs sk so sync sclk din 04767-035 ad5040/ ad5060 1 adsp-bf53x 1 1 additional pins omitted for clarity dt0pri tsclk0 tfs0 din sclk sync 04767-033 ad5040/ ad5060 1 figure 49. ad5040/ad5060 to microwire interface figure 47. ad5040/ad5060 to blackfin? adsp-bf53x interface ad5040/ad5060 to 80c51/80l51 interface figure 48 shows a serial interface between the ad5060/ ad5040 and the 80c51/80l51 microcontroller. the setup for the interface is: txd of the 80c51/80l51 drives sclk of the ad5040/ad5060 while rxd drives the serial data line of the part. the sync signal is again derived from a bit- programmable pin on the port. in this case, port line p3.3 is used. when data is to be transmitted to the ad5040, p3.3 is taken low. the 80c51/80l51 transmits data only in 8-bit bytes; thus only 8 falling clock edges occur in the transmit cycle. to load data to the dac, p3.3 is left low after the first eight bits are transmitted, and a second write cycle is initiated to transmit the second byte of data. p3.3 is taken high following the completion of this cycle. the 80c51/80l51 outputs the serial data in a format which has the lsb first. the ad5040/ad5060 require data to be received with the msb as the first bit. the 80c51/80l51 transmit routine should take this into account. 80c51/80l51 1 1 additional pins omitted for clarity p3.3 txd rxd sync sclk din 04767-034 ad5040/ ad5060 1 figure 48. ad5040/ad5060 to 80c51/80l51 interface
ad5040/ad5060 rev. a | page 19 of 24 applications choosing a reference for the ad5040/ ad5060 to achieve the optimum performance from the ad5040/ ad5060, carefully choose a precision voltage reference. the ad5040/ad5060 have just one reference input, v ref . the voltage on the reference input is used to supply the positive input to the dac. therefore, any error in the reference is reflected in the dac. there are four possible sources of error to consider when choosing a voltage reference for high accuracy applications: initial accuracy, ppm drift, long-term drift, and output voltage noise. initial accuracy on the output voltage of the dac leads to a full-scale error in the dac. to minimize these errors, a reference with high initial accuracy is preferred. also, choosing a reference with an output trim adjustment, such as an adr43x device, allows a system designer to trim out system errors by setting a reference voltage to a voltage other than the nominal. the trim adjustment can also be used at temperature to trim out any errors. because the supply current required by the ad5040/ad5060 is extremely low, the parts are ideal for low supply applications. the adr395 voltage reference is recommended. this requires less than 100 a of quiescent current and can, therefore, drive multiple dacs in one system, if required. it also provides very good noise performance at 8 v p-p in the 0.1 hz to 10 hz range. sync sclk din 7v 5v v out = 0v to 5v adr395 04767-036 3-wire serial interface ad5040/ ad5060 figure 50. adr395 as reference to ad5060/ad5040 long-term drift is a measure of how much the reference drifts over time. a reference with a tight long-term drift specification ensures that the overall solution remains relatively stable during its entire lifetime. the temperature coefficient of a reference output voltage affects inl, dnl, and tue. a reference with a tight temperature coefficient specification should be chosen to reduce the temperature dependence of the dac output voltage on ambient conditions. in high accuracy applications, which have a relatively low noise budget, reference output voltage noise needs to be considered. it is important to choose a reference with as low an output noise voltage as practical for the system noise resolution required. precision voltage references, such as the adr435, produce low output noise in the 0.1 hz to 10 hz region. table 8 shows examples of recommended precision references for use as a supply to the ad5040/ad5060. table 8. precision references for the ad5040/ad5060 part no. initial accuracy (mv max) temp. drift (ppm/c max) 0.1 hz to 10 hz noise (v p-p typ) adr435 2 3 (so-8) 8 adr425 2 3 (so-8) 3.4 adr02 3 3 (so-8) 10 adr02 3 3 (sc70) 10 adr395 5 9 (tsot-23) 8 bipolar operation using the ad5040/ ad5060 the ad5040/ad5060 have been designed for single-supply operation, but a bipolar output range is also possible using the circuit in figure 51 . the circuit shown yields an output voltage range of 5 v. rail-to-rail operation at the amplifier output is achievable using an ad8675/ad820/ad8032 or an op196/ op295. the output voltage for any input code can be calculated as ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? + ? ? ? ? ? ? = 1r 2r v 1r 2r1rd vv dd dd o 65536 where d represents the input code in decimal (0 to 65536, ad5060). with v ref = 5 v, r1 = r2 = 10 k: v5 65536 10 ? ? ? ? ? ? ? = d v o using the ad5060, this is an output voltage range of 5 v with 0x0000 corresponding to a ?5 v output and 0xffff corresponding to a +5 v output . +5v 10 f 04767-037 r1 = 10k v out v ref 0.1 f 3-wire serial interface ad820/ op295 + ? ?5v +5v r2 = 10k 5v ad5040/ ad5060 figure 51. bipolar operation with the ad5040/ad5060
ad5040/ad5060 rev. a | page 20 of 24 using the ad5040/ad5060 with a galvanically isolated interface chip in process control applications in industrial environments, it is often necessary to use a galvanically isolated interface to protect and isolate the controlling circuitry from any hazardous common-mode voltages that can occur in the area where the dac is functioning. i coupler? provides isolation in excess of 2.5 kv. because the ad5040/ad5060 use a 3-wire serial logic interface, the adum130x family provides an ideal digital solution for the dac interface. the adum130x isolators provide three independent isolation channels in a variety of channel configurations and data rates. they operate across the full range from 2.7 v to 5.5 v, providing compatibility with lower voltage systems as well as enabling a voltage translation functionality across the isolation barrier. figure 52 shows a typical galvanically isolated configuration using the ad5040/ad5060. the power supply to the part also needs to be isolated; this is accomplished by using a transformer. on the dac side of the transformer, a 5 v regulator provides the 5 v supply required for the ad5040/ad5060. 0.1 f 10 f v dd gnd power 5v regulator 04767-038 adum1300 sclk v0a v1a sclk v out sync v0b v1b sdi din v0c v1c data ad5040/ ad5060 figure 52. ad5040/ad5060 with a galvanically isolated interface power supply bypassing and grounding when accuracy is important in a circuit, it is helpful to carefully consider the power supply and ground return layout on the board. the printed circuit board containing the ad5040/ ad5060 should have separate analog and digital sections, each having its own area of the board. if the ad5040/ad5060 are in a system where other devices require an agnd-to-dgnd connection, the connection should be made at one point only. this ground point should be as close as possible to the ad5040/ad5060. the power supply to the ad5040/ad5060 should be bypassed with 10 f and 0.1 f capacitors. the capacitors should be physically as close as possible to the device with the 0.1 f capacitor ideally right up against the device. the 10 f capacitors are the tantalum bead type. it is important that the 0.1 f capacitor has low effective series resistance (esr) and effective series inductance (esi), as do common ceramic types of capacitors. this 0.1 f capacitor provides a low impedance path to ground for high frequencies caused by transient currents due to internal logic switching. the power supply line itself should have as large a trace as possible to provide a low impedance path and reduce glitch effects on the supply line. clocks and other fast switching digital signals should be shielded from other parts of the board by a digital ground. avoid crossover of digital and analog signals, if possible. when traces cross on opposite sides of the board, ensure that they run at right angles to each other to reduce feedthrough effects on the board. the best board layout technique is the microstrip technique where the component side of the board is dedicated to the ground plane only, and the signal traces are placed on the solder side. however, this is not always possible with a two-layer board.
ad5040/ad5060 rev. a | page 21 of 24 outline dimensions compliant to jedec standards mo-178-ba 121608-a 8 4 0 seating plane 1.95 bsc 0.65 bsc 0.60 bsc 76 1234 5 3.00 2.90 2.80 3.00 2.80 2.60 1.70 1.60 1.50 1.30 1.15 0.90 0 .15 max 0 .05 min 1.45 max 0.95 min 0.22 max 0.08 min 0.38 max 0.22 min 0.60 0.45 0.30 pin 1 indicator 8 figure 53. 8-lead small outline transistor package [sot-23] (rj-8) dimensions shown in millimeters ordering guide model 1 temperature range maximum inl description package description package option branding ad5040brjz-500rl7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d4c ad5040brjz-reel7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d4c ad5060arjz-1500rl7 ?40c to +85c 2 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d3z AD5060ARJZ-1REEL7 ?40c to +85c 2 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d3z ad5060arjz-2reel7 ?40c to +85c 2 lsb 2.7 v to 5.5 v, reset to mid- scale 8 lead sot-23 rj-8 d41 ad5060arjz-2500rl7 ?40c to +85c 2 lsb 2.7 v to 5.5 v, reset to mid- scale 8 lead sot-23 rj-8 d41 ad5060brjz-1500rl7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d3w ad5060brjz-1reel7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d3w ad5060brjz-2reel7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to mid- scale 8 lead sot-23 rj-8 d3x ad5060brjz-2500rl7 ?40c to +85c 1 lsb 2.7 v to 5.5 v, reset to mid- scale 8 lead sot-23 rj-8 d3x ad5060yrjz-1500rl7 ?40c to +125c 1.5 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d6f ad5060yrjz-1reel7 ?40c to +125c 1.5 lsb 2.7 v to 5.5 v, reset to 0 v 8 lead sot-23 rj-8 d6f eval-ad5060ebz evaluation board 1 z = rohs compliant part.
ad5040/ad5060 rev. a | page 22 of 24 notes
ad5040/ad5060 rev. a | page 23 of 24 notes
ad5040/ad5060 rev. a | page 24 of 24 notes ? 2005-2010 analog devices, inc. all rights reserved. trademarks and registered trademarks are the prop erty of their respective owners. d04767-0-1/10(a)


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