i] a~~~~~ [ features true rlns measurement db measurements bipolar dc measurements tfigh accuracy/wide frequency response full floating input isolation... parallel bcd 'data outputs five input ranges 3% digits large 0.5" (13mm) led displays line powered in,dustry standard case design afpllcations ,accurate true rms measurement of complex ac or ac+dc waveforms decibel oisplay of ac or ac+dc inputs for use in test equipment, power controllers, process control equipment and analytical and scientific instruments general description the ad2033 is a 3 ~ digit, led display, line-powered digital panel meter (dpm) that measures dc and ac inpu t signals. the ad2033 measures either the true rms value of ac+dc signals or the db value of the ac+dc inpu ts. the input of the ad203 3 is dc coupled and therefore accepts ac and/or dc inputs. the input can be ac coupled if it is desired to measure an ac signal riding on a constant dc voltage, as in measuring the ripple of a dc power supply. truermsmeasurements unlike most ac meters which display rms but measure the rectified average of ac input signals, the ad2033 uses im- plicit compu ting techniques to derive the actual rms value of the ac signals. thus, the accuracy of the ad2033 does not depend on input waveforms. pulse trains, triangular pulses and scr chopped sinewaves, even with high crest factors (ratio of peak to rms) and pure sinewaves, are all measured with high accuracy and no recalibration over a wide frequency range. db measurements db measurements can be made with respect to internal or external references (including standard imw /600s1 used in audio measurements). in either case, internal or external, the measurements are made with regard to a voltage level from +5mv to +5v. with internal reference, the voltage can be adjusted via a built-in reference adjust pot. db measurements can also be made against an arbitrary external true rms / db m.ultirange,~meter. .'ad2033 , i reference, either constant or slow varying. the external reference is applied to a pin on the top rear connector, and may be divided down from a higher reference voltage. five input ranges the ad2033 provides five separate inputs: 199.9mv; 1.999v; 19.99v; 199.9v and 600v rms full scale (fs). 1000v rms fs input is available upon special request. when reading is db, these input ranges are extended to 500mv, 5v, soy, soov and 62sv rms. factory calibration provides excellent accuracies on all five ranges, but the standardunit is optimized for the 1.999v rms fs range. optimized calibration for the other ranges is also available. the floating opto-isolated analog input withstands common mode voltages up to 300v rms, even with digital outputs and control lines connected. this not only facilitates making measurements in various electrical environments, but is essential in making current measure- ments which are rarely referenced directly to ground. second generation dpm design the use of mos/lsi (metal oxide semiconductor/large scale integration) integrated circuits in the ad2033 reduces the number of components, cuts power consumption and greatly increases reliability. 1m -~ -~-- obsolete
. bi;scurrent': 1na on all ranges except 200mv (lona) . overvoltage protection: 62sv rms sustained on all ranges except 200mv fs (l20v rms) . common mode voltage: 300v rms max at 60hz . common mode rejection at 60hz: f$. input a b c d e cmr 100db 80db 7sdb 60db 40db . temperature range: operating 0 to +so"c; storage -2soc to +8soc . settling time to rated accuracy: 2 seconds . provisions for external capacitor to extend low frequency response (reference applications section) . warm-up time: 20 minutes to rated accuracy conversion rate displav blanking (ttlldtl compatible. 1 ttl load) - logic "0" or gro\lnding blanks entire display except for decimal points; logic "i" or open circuit for normal operation. display blanking has no eff~ct on output data. display is valid immediately upon removal of blank- ing input. converter hold (cmos/ttlldtl compatible, i lpttl load) - logic "0" or grounding causes dpm to ccase conversions and display data from last conversion; logic "i" or open circuit for normal operation. after "converter hold" is removed, one or two conversions arc needed before reading and bcd data arc valid. decimal points (not ttl compatilili:.) - logic "0" or grounding illumi- nates desired decimal point. external drive circuitry must sink 25ma peak at a 2s% duty cyele, when decimal point is illuminated. data hold (ttlldtl compatible, i ttl load) - logic "0" or ground- ing inhibits updating of latched parallel output data; logic "i" or open circuit allows data to be updated after each dpm conversion. this input has no effect on the normal conversion of the di'm and its display. data outputs isolated parallel bcd ou~- 3 bcd digits, overrange, overload and data ready outputs (ttl compatible, 4 ttl loads). bcd data outputs are latched, positive true logic. overload output is logic "0" for inputs greater than full scale range. logic" 1 " when other data out- puts are valid. polarity output (ttl compatible, 4 ttl loads latched) indicates positive polarity when high (logic "i"). digital outputs are fully isolated from input circuitry; all logic levels are referenced to digital ground. bipolar dc measurements . full scale input: :!: 1.999v dc (see ad2022 data sheet for complete information) power input . ac line so-400hz . power consumption: 6.8 watts at 60hz calibration adjustments . input offset . zero width . gain . internal (db) reference adjust . recommended calibration interval: 6 months size . 3.92"w x 1.67"h x 4.48"d (100 x 42 x 114mm) . panel cutout: 3.924" x 1.682" (99.8 x 42.7mm) . ac power inputs (no cost option) (so-400hz) ad2033 - 1i7v ac i ad2033/e - 220v ac ad2033/f - 100v ac . :!:io% ad2033/h - 240v ac . display lens options' lens 7 - red with ad! logo lens 8 -- red without adi logo . ad2033 converter card connector pi 30 pin, 0.156" spacing card cdge connector, viking 2vki5011-2 optional order aci50 1 . ad2033 rms/db card connector 1'2 36 pin, 0.156" spacing card edge connecror, viking 2vki8d/i-2 optional: order ac2610 'overrange of 250% of full scale is available for analog only output (pin r) on all ranges except e. for e overlange capability is 4%. 'iooov is optional, contact factory. 3 bias current approximately doubles for each change in ambient temperature of +woc. 'lens 7 is supplied if no lens option is specified. specifications subject to change without notice. --~ obsolete
ranjc , . accuracy dc or 30hz to 13khz sinewave temperature coefficient: zero gain frequency response: (sinewave input) :tl% rdg :1:0.05% i's :1:1 digit (max error) 3db (max error) ~ 30hz to 10khz 30hz to 10khz 30hz to 100khz 30hz to 100khz 30hz to 10khz 30hz to 10khz 30hz to 5khz 30hz to 100khz 30hz to 100khz 30hz to 30khz table 1. ad2033 rms specifications applying the ad20h description of operation the timing and block diagrams are shown in figures 1 and 2 respectively. the input pin for all ranges except range a is pin k. range a input connects to pin e. the input signal is fed into a buffer amplifier. range selection is made by connecting the appropriate feedback resistor. the bias current compensate (pin b), for stabilization of bias current over extended temperatures, should be tied to ground on all conversion cycle i i r !-133m.-1--67ms--1 ~- 2m. (approx.) 1'1-. data ready data valid 1r- u figure 1. ad2033 timing diagram ranges except range b. the output of the buffer amplifier drives a true rids to dc converter that combines loga- rithmic and implicit computing techniques to achieve low overall error and a wide dynamic range, as in the equation: v \ = j 1 rot (v )2 dt rids t jo in for true rids readout, the above is used as the aid input. it also drives the log ratio circuitry which develops a db output relative to either internal or external referenc~ voltage- for do readout, the log ratio output feeds the aid input. the aid conversion is performed via a special technique ("charge balancing") that requires interaction between analog and digital processing. the analog processor provides buffering, integration, autozeroing and comparison functions. the digital processor contains control, counting, storage and data multiplexing functions. as can be seen from the block diagram, the two processors are opto and pulse transformer isolated. this isolation increases dpm tolerance to front end noise and high common mode voltage. the output of the digital processor drives the display via a seven segment decoder driver and is also available via the parallel bcd data storage. true rms measurements a typical setup for measuring 1.999v rids fs (range b) can be accomplished by linking feedback range select (pin a) to feedback (pin f). connect 1. 999v source between input (pin k) and ground (pins 1-6). then connect rids/dc fashion in setting up for all other ranges except when using r , feedback range select i i i i i i i i i ext. cap idptional} i i i i i i i i ici feedback i 0 range e {difeedback i iai j 0 range d feedback i 12 ranges mb l e i feedback ' i range c '-~ ' 0 input range a (~iinput ranges b,c,d.e 1k 101< 1m analog grd. ipins 1-61 iu) db reference in vref 117) db reference out i i- i - i::; i~ lis 1\; i~ i" i~ i~ ," i l i i i i i i _1~l~t~ !!'~!.~~ i i i i i j.. -,- i i , , iri vsog i 'ms-dc out i oivi i db output i i i i i (ib) aid input i5i'1xxx multiplexed display i - ) 'pi idiconv hold ~..n" i ,'m ?'"0 polarity update control figure 2. ad2033 block diagram 1m) iii 1'31 ij bcd data imul tiplexedi data hold 111 status 131 the 199. 9m v rms fs range where pin k must be grounded and the input must go to pin e. the bias current compen- sate (pin b) must be connected to ground on all ranges except the 1.999v rids fs. applying the ad2033 199.9mv rids 1.999v rids 19.99v rids 199.9v rids 600v rms :1:1.2% rdg :1:0.1% rdg :1:0.3% rdg :1:0.3% rdg :1:1.2% rdg :1:0.05% fs :1:0.05% fs . :1:0.05% fs :1:0.05% fs :1:0.05% fs :1:1 digit :1:1 digit :1:1 digit :1:1 digit :1:1 digit :l:20jj.v/c :l:60jj.v/c :to.6m v / c :t6mv/c :t60mv/c :t75ppm/oc :t75ppm/c :t75ppm/c . :t75ppm/c :t75ppm/oc obsolete
/"\~ ~iluwil iii r igun; :>, ud reaaou r ror a par(icular v sig can be varied by controlling vref' either via the internal refer- ence adjust or by control of an external reference (which can can be divided down from a higher voltage). 'o.sdb accuracy '1sdb accuracy vaef note' figure 3 is set up for absolute voltages on the 5v scale. 2odb correction per decade would be needed if vaef remains absolute on other ranges caution there is no input overload indication in d8 mode figure 3. db readout as a function of vsig and v ref adjustment of the db range can also be accomplished by selecting the proper v sig inpu t range and v ref' the 60db readout range can be offset anywhere within the total meter range of +60db to -60db. examples: 1. vsig = sov rms on the sov ems range with vref = sv. db readout = o.oodb and the full db readout range is o.oodb to -60db. 2. vsic:; = sov ems on the soov rms range with vref = o.sv. db readout = o.oodb and the full db readout range is +20db to -40db. to set up for a full scale of soomv input range, link feed- back range select (pin a) to feedback (pin f). connect source between 200mv input (pin e) and ground (pins 1-6). connect db reference in (pin u) to db reference out (pin 17) for use of internal reference and then link db out- put (pin v) to aid input (pin 18). to use external reference, connect source between db reference in (pin u) and analog ground (pins 1-6). since the input pin for this range is pin e, key the input pin (pin k) for all other ranges must be grounded and the bias current compensate must be linked to ground (pins 1-6) on all ranges except the 1.999v rms fs range. set up in similar fashion on other ranges. bipolar dc measurements by bypassing the nos/db front end, it is possible to use the ad2033 to measure and display a bipolar dc value on the 1.999v fs. the input pin for this measurement would be the aid input pin (pin 18 of p2). connect low side to ground (pins 1-6). a shunt capacitor (0.047/-lf) at the aid input is needed to limit input impedance. ac coupling input of ad20h for measurements of ac voltages superimposed upon de >c voltage, put the following dc blocking capacitors at dpm'm input: range 200mv all others capacitor (rated accuracy at 45hz) i/-lf 0.1/-lf measurement of very low frequencies. if the input signal to be measured has a frequency of dc to about 30hz, the ad2033 will "track" the input signal and vol. ii, 16-46 digital panel instruments extend the low trequency response ot the ad2033, cwo pins are provided at the connector of p2 to allow an external capacitor to be attached. table 2 will aid in choosing the proper value of averaging capacitance. table 2. external capacitor selection interfacin~ data outputs - parallel bcd the ad20b has data outputs in a full parallel bcd format. the output data is latched and is valid except for a 2ms period at the end of conversion, when the "data ready" output is high (see figure 1). as described above, the "data hold" input can be used to inhibit updating of the parallel dara outputs without affecting dpm conversions or the dpm display. extended true ems ac range measurements although the full scale display range of the ad2033 is 1999 counts, and the display flashes to indicate overrange beyond this point, measurements are actually made up to approxi- mately 3000 counts. since it is impossible to display "2" in the most significant digit of the ad2033, overrange from 2000 to 2999 counts produces a flashing display of the 3 least significant digits only (a reading of 2.300mv displays as "300" flashing). overrange beyond 2999 counts is indi- cated by a constant number flashing. thus, one can use the extra range measurements as a guide to reducing the input to the normal range. the parallel bcd outputs of the ad20b beyond 1999 counts go to logic "0" on all bcd lines, as does the overload output. ikey figure 4. ad2033 connector p1 key ... key figure 5. ad2033 connector p2 soov 50v 5v 0.5v l l l 625v il - soovi 50vi 5v sovl 5vl 0.5v! 0.05\1 o.oo5v z " 20v! 2vi 02vi 0.02v 5v 0.5v 0.05v o.oo5v averaging capacitor settling time tl? frequency value rated accuracy 25hz is/-lf 6 seconds 10hz 100/-lf 30 seconds pin function 1 data hold 2 3 data ready 4 polarity bcd 8 bcd 2 7 bcd80 8 bcd 20 9 bcd 800 10 11 bcd 400 12 bcd 200 13 display blank 14 overrange 15 ac line high pin function a n/c b n/c c overload 0 converter hold -t bcd 1 bcd 4 .h bcd 10 j bcd 40 k bcd 100 l dp3 xx.x m dp2 x.xx n digital ground p dp1 .xxx r shield (earth ground) s ie line low pin function 1 analog low 2 analog low 3 analog low 4 analog low r-i analog low analog low 7 8 9 10 11 12 13 14 16 16 17 db ref out (0 to .sv) 18 aid input tl.999v fs , pin function a range select (connect to c,d,e.f) b bias current compensate c range e feedback 0 range 0 feedback -f range c range a and b h j k input (except 200mv) l m n rml out t1.999v'fslex":'cap (+\ r s ext cap h to db rep in (optional) .u db ref in (+&mv .. vriv .. .svi v db out (2oomvidecade) obsolete
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