1 m e m o r y 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 7846A ?2003 maxwell technologies all rights reserved. 05.29.03 rev 5 f eatures : ?r ad -p ak ? technology-hardened against natural space radiation 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? 7846A 16-bit dac converter microcir- cuit features a greater than 100 krad (si) total dose tolerance, depending upon space mission. the 7846A has v ref+ and v ref- reference inputs and an on-chip output amplifier which gives the option of unipolar or bipolar output. the 7846A 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 archi- tecture ensures 16-bit monotonicity. excellent integral linearity results from tight matching between the input offset voltages of the two buffer amplifiers. in addition to the excellent accu- racy specifications, the 7846A also offers a comprehensive microprocessor 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 shielding in the microcircuit pack- age. it eliminates the need for box shielding while providing the required radiation shielding for a lifetime in orbit or space mission. in a geo orbit, r ad -p ak provides greater than 100 krad (si) radiation dose tolerance. 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 7846A
m e m o r y 2 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 t able 1. 7846A 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 circuitry. 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 -5v. the device is specified for both conditions. 9v ss negative supply for the analog circuitry. 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 circuitry. 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.
m e m o r y 3 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 t able 2. 7846A a bsolute m aximum r atings 1 1. stresses above those listed under ?absolute maximum ratings? may cause permanent damage to the device. this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational se c- tions of this specification is not implied. exposure to absolute maximum rating conditions 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 dgnd -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 dissipation 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 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.
m e m o r y 4 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 t able 4. 7846A e lectrical s pecifications 1 (vdd=+15v 5%; vss=-15v 5%; v cc = +5 v 5%, t a = -55 to +125c) p arameter t est c onditions /c omments s ubgroups t a =-55 c to +125 c u nit resolution 16 bits unipolar output relative accuracy @ 25 c - t min to t max differential nonlinearity 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=153 v guaranteed monotonic v out load= 10m ? 1 2, 3 1 1 2,3 1 2,3 1 1 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 nonlinearity 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=305 v guaranteed monotonic v out load=10m ? v out load=10m ? 1 2, 3 1 1 2, 3 1 2, 3 1 2, 3 1 1 1 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 1 capacitive load 3 output resistance short circuit current 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) c in (input capacitance) 2 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 2 i sink = 1.6ma i source = 400 a db0-db15 = 0 to v cc 1, 2, 3 0.4 4.0 10 10 v max v min a max pf max
m e m o r y 5 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 power requirements 4 v dd v ss v cc i dd i ss i cc power supply sensitivity 5 power dissipation v out unloaded v out unloaded v out unloaded 1, 2, 3 +11.4/+15.75 -11.4/-15.75 +4.75/+5.25 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. maximum load is 1000pf. 4. 7846Arp is functional with power supplies of 12v. see typical performance curves. 5. sensitivity to gain error, offset error and bipolar zero error to v dd , v ss variations. 6. guaranteed by design t able 5. 7846A ac p erformance c haracteristics 1 (vdd=+15v 5%; vss=-15v 5%; 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 density (1khz-100khz) measured at v out . dac loaded with 0111011?11. v ref+ =v ref- =0v. 50 50 nv/(hz) ? typ t able 4. 7846A e lectrical s pecifications 1 (vdd=+15v 5%; vss=-15v 5%; v cc = +5 v 5%, t a = -55 to +125c) p arameter t est c onditions /c omments s ubgroups t a =-55 c to +125 c u nit
m e m o r y 6 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 t able 6. 7846A 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 control 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 figure 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
m e m o r y 7 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 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 valid 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 cs data clr ldac 0v 5 v 0v 5 v 0v 5v 5v 0 v 5v 0v
m e m o r y 8 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5
m e m o r y 9 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 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
m e m o r y 10 all data sheets are subject to change without notice ?2003 maxwell technologies all rights reserved. 16-bit digital to analog converter 7846A 05.29.03 rev 5 important notice: these data sheets are created using the chip manufacturers published specifications. maxwell technologies verifies functionality by testing key parameters either by 100% testing, sample testing 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 use of this information. maxwell technologies? products are not authorized for use as critical components in life 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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