1 memory all data sheets are subject to change without notice (619) 503-3300 - fax: (619) 503-3301- www.maxwell.com 16-bit digital to analog converter 7846 ?2002 maxwell technologies all rights reserved. 02.19.02 rev 4 f eatures : ?r ad -p ak ? technology-hardened agains t natural space radi- ation ? total dose hardness: - > 100 krad (si), depending upon space mission ? excellent single event effects - sel th > 114 mev/mg/cm 2 - seu < 8 mev/mg/cm 2 ? package: -28 pin r ad -p ak flat pack ? microprocessor compatible with readback capability ? 16-bit monotonicity over temperature ? 2 lsbs integral linearity error ? unipolar or bipolar output ? multiplying capability ? low power (100 mw typical) d escription : maxwell technologies? 7846 16-bit dac converter microcircuit features a greater than 100 krad (si) total dose tolerance, depending upon space mission. the 7846 has v ref+ and v ref- reference inputs and an on-chip output amplifier which gives the option of unipolar or bipolar output. the 7846 uses a segmented architecture. the 4 msbs in the dac latch select one of the segments in a 16-resistor string. both taps of the segment are buffered by amplifiers and fed to a 12-bit dac, which provides a further 12 bits of resolution. this architecture ensures 16-bit monotonicity. excell ent integral linearity results from tight matching between the input offset voltages of the two buffer amplifiers. in addition to the excellent accuracy specifications, the 7846 also offers a comprehensive micro- processor interface. there are 16 data i/o pins, plus control lines (cs , r/w , ldac and clr ). r/w and cs have readback function which allows writing to and reading from the i/o latch. maxwell technologies' patented r ad -p ak ? packaging technol- ogy incorporates radiation shie lding in the microcircuit pack- age. it eliminates the need for box shielding while providing the required radiation shielding fo r a lifetime in orbit or space mission. in a geo orbit, r ad -p ak provides greater than 100 krad (si) radiation dose toleranc e. this product is available with screening up to class s. 16 segment switch matrix control logic a2 a1 a3 i/o latch dac latch 12-bit dac - + - + - + r r 6 5 23 22 25 24 20 3 10 9 8 7 21 4 v dd v cc v ref+ v ref- v ss db15 db0 dgnd clr ldac r/w cs v out r in 12 12 4 r r r logic diagram
memory 2 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 t able 1. 7846 p inout d escription p in s ymbol d escription 1-3 db2-db0 data i/o pins. db0 is lsb. 4v dd positive supply for analog circui try. this is +15v nominal. 5v out dac output voltage pin. 6r in input to summing resistor of dac output amplifier. this is used to select output voltage ranges. 7v ref+ v ref+ input. the dac is specified for v ref+ = +5v. 8v ref- v ref- input. for unipolar operation connect v ref- to 0v and for bipolar operation connect it to -5 v. the device is specified for both conditions. 9v ss negative supply for the analog circui try. this is -15v nominal. 10-19 db15-db6 data i/o pins. db15 is msb. 20 dgnd ground pin for digital circuitry. 21 v cc positive supply for digital circ uitry. this is +5v nominal. 22 r/w r/w input. this can be used to load data to the dac or to read back the dac latch contents. 23 cs chip select input. this selects the device. 24 clr clear input. the dac can be cleared to 000...000 or 100...000. 25 ldac asynchronous load input to dac. 26-28 db5-db3 data i/o pins.
memory 3 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 t able 2. 7846 a bsolute m aximum r atings 1 1. stresses above those listed under ?absolute maximum ratings? ma y cause permanent damage to the device. this is a stress rating only and functional oper ation of the device at these or any other c onditions above those indicated in the operational se c- tions of this specification is not impl ied. exposure to absolute maximum rating c onditions for extended periods of time may affect device reliability. only one absolute maximum rating may be applied at any one time. p arameter m in m ax u nit v dd to dgnd -0.3 +17 v v cc to dgndpcvc -0.3 v dd +0.3 or 7 (whichever is lower) v v ss to dgnd -17 +0.3 v v ref+ to dgnd -25 +25 v v ref- to dgnd -25 +25 v v out to dgnd 2 2. v out may be shorted to dgnd, v dd , v ss and v cc provided that the power dissipat ion of the package is not exceeded. -25 +25 v r in to dgnd -25 +25 v digital input voltage to dgnd -0.3 v cc +0.3 v digital output voltage to dgnd -0.3 v cc +0.3 v power dissipation (any package) to +75 c derates above +75 c 1000 10 mw mw/ c thermal inpedance jc 2.78 c operating temperature range -55 +125 c storage temperature range -65 +150 c t able 3. d elta l imits p arameter v ariation i dd 10% of value specified in table 4. i ee 10% of value specified in table 4. i cc 10% of value specified in table 4.
memory 4 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 t able 4. 7846 e lectrical s pecifications 1 (v cc = +5 v 5%, t a = -55 to +125c) p arameter t est c onditions /c omments s ubgroup t a =-55 c to +125 c u nit resolution 16 bits unipolar output relative accuracy @ 25 c - t min to t max differential nonl inearity error gain error @ 25 c - t min to t max offset error @ 25 c - t min to t max gain tc 2 offset tc 2 v ref- =0v, v out =0v to +10v 1lsb=153v guaranteed monotonic v out load= 10m ? 1 2, 3 1 2, 3 1 2, 3 16 16 1 12 24 12 24 2 2 lsb typ lsb max lsb max lsb typ lsb max lsb typ lsb max ppm fsr/c typ ppm fsr/c typ bipolar output relative accuracy @ 25 c - t min to t max differential nonl inearity error gain error @ 25 c - t min to t max offset error @ 25 c - t min to t max bipolar zero error @ 25 c - t min to t max gain tc 2 offset tc 2 bipolar zero tc 2 v ref- =-5v, v out =-10v to +10v 1lsb=305v guaranteed monotonic v out load=10m ? v out load=10m ? 1 2, 3 1 2, 3 1 2, 3 1 2, 3 6 8 1 6 16 6 16 6 16 2 2 2 lsb typ lsb max lsb max lsb typ lsb max lsb typ lsb max lsb typ lsb max ppm fsr/ c typ ppm fsr/ c typ ppm fsr/ c typ reference input input resistance v ref+ range v ref- range resistance from v ref- to v ref+ typically 30k ? 1, 2, 3 20 40 v ss + 6 to v dd - 6 v ss + 6 to v dd - 6 k ? min k ? max v v output characteristics output voltage swing resistive load 6 capacitive load 6 output resistance 6 short circuit current 6 to 0v to 0v to 0v or any power supply 1, 2, 3 v ss + 4 to v dd - 3 3 1000 0.3 25 v max k ? min pf max ? typ ma typ digital inputs v ih (input high voltage) v il (input low voltage) i in (input current) 6 c in (input capacitance) 6 1, 2, 3 2.4 0.8 10 10 v min v max a max pf max digital outputs v ol (output low voltage) v oh (output high voltage) floating state leakage current floating state output capacitance 6 i sink = 1.6ma i source = 400a db0-db15 = 0 to v cc 1, 2, 3 0.4 4.0 10 10 v max v min a max pf max
memory 5 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 power requirements 3 v dd v ss v cc i dd i ss i cc power supply sensitivity 4 power dissipation +11.4/+15.75 -11.4/-15.75 +4.75/+5.25 v out unloaded v out unloaded v out unloaded 1, 2, 3 1, 2, 3 1, 2, 3 5 5 1 2 100 v min/v max v min/v max v min/v max ma max ma max ma max lsb/v max mw typ 1. minimum load is 3k ? . 2. sample tested to ensure compliance. 3. 7846rp is functional with power supplies of 12v. see typical performance curves. 4. sensitivity to gain error, offset error and bipolar zero error to v dd , v ss variations. 6. guaranteed by design t able 5. 7846 ac p erformance c haracteristics 1 (v cc = +5 v 5%, t a = -55 to +125c) 1. guaranteed by design. p arameter t est c onditions t a =25 c t a =t min to t max u nit output settling time to 0.006% fsr. v out loaded. v ref- =0v. 7 7 s max to 0.003% fsr. v out loaded. v ref- =-5v. 9 9 s max digital-to-analog glitch impulse dac alternately loaded with 10?0000 and 01?1111. v out unloaded. 400 400 nv-secs typ ac feed through v ref- =0v, v ref+ =1v rms, 10khz sine wave. dac loaded with all 0s. 0.5 0.5 mv pk-pk typ digital feed through dac alternately loaded with all 1s and all 0s. cs high. 10 10 nv-secs typ output noise voltage den- sity (1khz-100khz) measured at v out . dac loaded with 0111011?11. v ref+ =v ref- =0v. 50 50 nv/(hz) ? typ t able 4. 7846 e lectrical s pecifications 1 (v cc = +5 v 5%, t a = -55 to +125c) p arameter t est c onditions /c omments s ubgroup t a =-55 c to +125 c u nit
memory 6 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 t able 6. 7846 t iming c haracteristics 1,2,3,4 (v dd = +14.25v to 15.75v; v ss = -14.25v to -15.75v; v cc = 4.75 to 5.25v; unless otherwise specified ) 1. guaranteed by design. all input c ontrol signals are specified with t r = t f = 5ns (10% to 90% of +5v) and timed from a voltage level of 1.6v. 2. t 6 is measured with the load circuits of figure 1 and defined as the time required for an output to cross 0.8v or 2.4v. 3. t 7 is defined as the time required for an output to change 0.5v when loaded with the circuits of figur e 2. specifications subject to change without notice. 4. see figure 3 on page 7. p arameter t est c onditions /c omments l imit a t t a =-55 c to +125 c u nit t 1 r/w to cs setup time 50 ns min t 2 cs pulse width (write cycle) 190 ns min t 3 r/w to cs hold time 50 ns min t 4 data setup time 120 ns min t 5 data hold time 0 ns min t 6 data access time 320 ns max t 7 bus relinquish time 10 ns min 90 ns max t 8 clr setup time 20 ns min t 9 clr pulse width 150 ns min t 10 clr hold time 0 ns min t 11 ldac pulse width 100 ns min t 12 cs pulse width (read cycle) 330 ns min
memory 7 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 f igure 1. l oad c ircuits for a ccess t ime (t 6 ) f igure 2. l oad c ircuits for b us r elinquish t ime (t 7 ) f igure 3. 16- bit d igital to a nalog c onverter data vali d data vali d t 1 t 2 t 3 t 3 t 12 t 1 t 4 t 5 t 6 t 7 t 8 t 9 t 1 0 t 8 t 9 t 10 t 11 r ./w c s dat a clr lda c 0 v 5v 0v 5v 0v 5v 5v 0v 5v 0v
memory 8 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4
memory 9 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 f28-02 note: all dimensions in inches 28 p in r ad -p ak ? f lat p ackage s ymbol d imension m in n om m ax a 0.190 0.207 0.224 b 0.015 0.017 0.022 c 0.004 0.005 0.009 d -- 0.720 0.740 e 0.380 0.410 0.420 e1 -- -- 0.440 e2 0.180 0.250 -- e3 0.030 0.080 -- e 0.050 bsc l 0.360 0.370 0.380 q 0.062 0.073 0.081 s1 0.000 0.027 -- n28
memory 10 all data sheets are subject to change without notice ?2002 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846 02.19.02 rev 4 important notice: these data sheets are created using the chip manufacturer s published specifications. maxwell technologies verifies functionality by testing key parameters either by 100% testing, sample test ing or characterization. the specifications presented within these data sheets represent the latest and most accurate information available to date. however, these specifications are subject to change without notice and maxwell technologies assumes no responsibility for the us e of this information. maxwell technologies? products are not authorized for use as critical components in li fe support devices or systems without express written approval from maxwell technologies. any claim against maxwell technologies must be made within 90 days from the date of shipment from maxwell tech- nologies. maxwell technologies? liability shall be limited to replacement of defective parts.
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