one technology way, p.o. box 9106, norwood, ma 02062-9106, u.s.a. tel: 617/329-4700 fax: 617/326-8703 functional block diagrams soic (so-8) metal can (h-02a) ? +v 1 2 3 4 8 7 6 5 ad589 top view +v ? bottom view rev. b 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 which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of analog devices. a two-terminal ic 1.2 v reference ad589 features superior replacement for other 1.2 v references wide operating range: 50 m a to 5 ma low power: 60 m w total p d at 50 m a low temperature coefficient: 10 ppm/ 8 c max, 0 8 c to +70 8 c (ad589m) 25 ppm/ 8 c max, C55 8 c to +125 8 c (ad589u) two-terminal zener operation low output impedance: 0.6 v no frequency compensation required low cost mil-std-883 compliant versions available product description the ad589 is a two-terminal, low cost, temperature compen- sated bandgap voltage reference which provides a fixed 1.23 v output voltage for input currents between 50 m a and 5.0 ma. the high stability of the ad589 is primarily dependent upon the matching and thermal tracking of the on-chip components. analog devices precision bipolar processing and thin-film technology combine to provide excellent performance at low cost. additionally, the active circuit produces an output impedance ten times lower than typical low-tc zener diodes. this feature allows operation with no external components required to maintain full accuracy under changing load conditions. the ad589 is available in seven versions. the ad589j, k, l and m grades are specified for 0 c to +70 c operation, while the s, t, and u grades are rated for the full C55 c to +125 c temperature range. all grades are available in a metal can (h-02a) package. the ad589j is also available in an 8-pin soic package. product highlights 1. the ad589 is a two-terminal device which delivers a constant reference voltage for a wide range of input current. 2. output impedance of 0.6 w and temperature coefficients as low as 10 ppm/ c insure stable output voltage over a wide range of operating conditions. 3. the ad589 can be operated as a positive or negative reference. floating operation is also possible. 4. the ad589 will operate with total current as low as 50 m a (60 m w total power dissipation), ideal for battery powered instrument applications. 5. the ad589 is an exact replacement for other 1.2 v ref- erences, offering superior temperature performance and reduced sensitivity to capacitive loading. 6. the ad589 is available in versions compliant with mil- std-883. refer to the analog devices military products databook or current ad589/883b data sheet for detailed specifications.
ad589Cspecifications C2C (typical @ i in = 500 m a and t a = +25 8 c unless otherwise noted) ad589 chip dimensions and pad layout 0.040 (1.016) 0.060 (1.524) the ad589 is available in chip form with fully tested and guaranteed specifications. consult factory for available grades and pricing. model ad589jh/jr ad589kh ad589lh ad589mh min typ max min typ max min typ max min typ max unit output voltage, t a = +25 c 1.200 1.235 1.250 1.200 1.235 1.250 1.200 1.235 1.250 1.200 1.235 1.250 v output voltage change vs. current (50 m aC5 ma) 5 5 5 5 mv dynamic output impedance 0.6 2 0.6 2 0.6 2 0.6 2 w rms noise voltage 10 hz < f < 10 khz 5 5 5 5 m v temperature coefficient 1 100 50 25 10 ppm/ c turn-on settling time to 0.1% 25 25 25 25 m s operating current 2 0.05 5 0.05 5 0.05 5 0.05 5ma operating temperature 0 +70 0 +70 0 +70 0 +70 c package option 3 metal can (h-02a) ad589jh ad589kh ad589lh ad589mh soic (r-8) ad589jr model ad589sh AD589TH ad589uh min typ max min typ max min typ max unit output voltage, t a = +25 c 1.200 1.235 1.250 1.200 1.235 1.250 1.200 1.235 1.250 v output voltage change vs. current (50 m aC5 ma) 5 5 5 mv dynamic output impedance 0.6 2 0.6 2 0.6 2 w rms noise voltage 10 hz < f < 10 khz 5 5 5 m v temperature coefficient 1 100 50 25 ppm/ c turn-on settling time to 0.1% 25 25 25 m s operating current 2 0.05 5 0.05 5 0.05 5ma operating temperature C55 +125 C55 +125 C25 +125 c package option 3 metal can (h-02a) ad589sh AD589TH ad589uh soic (so-8) ad589jr notes 1 see the following page for explanation of temperature coefficient measurement method. 2 optimum performance is obtained at currents below 500 m a. for current operation below 200 m a, stray shunt capacitances should be limited to 20 pf or increased to 1 m f. if strays can not be avoided, operation at 500 m a and a shunt capacitor of at least 1000 pf are recommended. 3 h = hermetic metal can; so = soic. specifications shown in boldface are tested on all production units at final electrical test. specifications subject to change without notice. absolute maximum ratings current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 ma reverse current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 ma power dissipation 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 mw storage temperature . . . . . . . . . . . . . . . . . . . C65 c to +175 c operating junction temperature range . . . . C55 c to +150 c lead temperature (soldering, 10 sec) . . . . . . . . . . . . . +300 c note 1 absolute maximum power dissipation is limited by maximum current through the device. maximum rating at elevated temperatures must be computed assuming t j 150 c, and q ja = 400 = c/w. rev. b
understanding the specificationsCad589 voltage variation vs. temperature some confusion exists in the area of defining and specifying reference voltage error over temperature. historically, references have been characterized using a maximum deviation per degree centigrade; i.e., 10 ppm/ c. however, because of nonlinearities in temperature characteristics, which originated in standard zener references (such as s type characteristics) most manufacturers have begun to use a maximum limit error band approach to specify devices. this technique involves measure- ment of the output at 3, 5 or more different temperatures to guarantee that the output voltage will fall within the given error band. the temperature characteristics of the ad589 consis- tently follows the curve shown in figure 1. three-point measurement guarantees the error band over the specified temperature range. the temperature coefficients specified on the previous page represent the slopes of the diagonals of the error band from +25 c to t min and +25 c to t max . 1.2370 1.2345 +125 1.2360 1.2350 ?5 1.2355 ?0 1.2365 +100 +75 +50 +25 0 temperature ?? output voltage ?v figure 1. typical ad589 temperature characteristics 1000 100 0 10 100 1m 100k 10k 1k 10 frequency ?hz noise spectral density ?nv/ hz figure 2. noise spectral density dynamic performance many low power instrument manufacturers are becoming increasingly concerned with the turn-on characteristics of the components being used in their systems. fast turn-on compo- nents often enable the end user to keep power off when not needed, and yet respond quickly when the power is turned on for operation. figure 3 displays the turn-on characteristics of the ad589. this characteristic is generated from cold-start opera- tion and represents the true turn-on waveform after an extended period with the supplies off. the figure shows both the coarse and fine transient characteristics of the device; the total settling time to within 1 millivolt is about 25 m s, and there is no long thermal tail appearing after that point. 10 90 100 0% 200mv 10 s 10mv figure 3. output settling characteristics r1 r5 r6 r2 r7 c1 q2 r4 q1 r3 q3 q4 ? +v q5 q8 q7 q9 figure 4. schematic diagram rev.b C3C
ad589 rev. b C4C application information the ad589 functions as a two-terminal shunt-type regulator. it provides a constant 1.23 v output for a wide range of input current from 50 m a to 5 ma. figure 5 shows the simplest configuration for an output voltage of 1.2 v or less. note that no frequency compensation is required. if additional filtering is desired for ultralow noise applications, minimum recommended capacitance is 1000 pf. 6.8k w 10k w ad589 v out +5v figure 5. basic configuration for 1.2 v or less the ad589 can also be used as a building block to generate other values of reference voltage. figure 6 shows a circuit which produces a buffered 10 v output. total supply current for this circuit is approximately 2 ma. ad589 +15v 7 6 8 1 4 3 2 0.01? ad108a 15k w 1k w 1k w 8.2k w 10v figure 6. single supply buffered 10 v reference the low power operation of the ad589 makes it ideal for use in battery operated portable equipment. it is especially useful as a reference for cmos analog-to-digital converters. figure 7 shows the ad589 used in conjunction with two popular integrating type cmos a/d converters. ad589 5.6k w 6.8k w 2k w +5v +v 7109 ref+ ref ref out a. with 7109 12-bit binary a/d printed in u.s.a. c547cC2C7/88 ad589 6.2k w 10k w 1k w +5v +v 7107 ref hi ref lo common b. with 7107 panel meter a/d figure 7. ad589 used as reference for cmos a/d converters the ad589 also is useful as a reference for cmos multiplying dacs such as the ad7533. these dacs require a negative reference voltage in order to provide a positive output range. figure 8 shows the ad589 used to supply an equivalent C1.0 v reference to an ad7533. ad589 2 1 16 r fb out1 out2 ref gnd v dd +15v r2 5k w 14 15 3 r1 39k w ?5v v out = 0 to 1.00v msb lsb 23456789 bit 1 bit 10 ad7533 series ad542l figure 8. ad589 as reference for 10-bit cmos dac outline dimensions and pin designations dimensions shown in inches and (mm). 0.10 (2.54) 45 0.500 (12.7) min dia 0.195 (4.95) 0.178 (4.52) 0.028 (0.71) 0.048 (1.22) 0.036 (0.91) 0.046 (1.17) dia 0.209 (5.31) 0.230 (5.84) 0.150 (3.81) 0.125 (3.17) 0.015 (0.38) 0.019 (0.48)
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