pin function pin function 1 bit 1 (msb) 24 +15v supply 2 bit 2 23 ground 3 bit 3 22 ?15v supply 4 bit 4 21 reference out 5 bit 5 20 bipolar offset 6 bit 6 19 10v range 7 bit 7 18 output 8 bit 8 17 20v range 9 bit 9 * 16 reference in 10 bit 10 * 15 ground 11 bit 11 * 14 ground 12 bit 12 (lsb) * 13 ground innovation and ex c ell e n c e ? ? features ? ? ? ? ? 8, 10 and 12-bit resolutions ? ? ? ? ? settling times to 25ns ? ? ? ? ? 20ppm/c max. gain tempco ? ? ? ? ? unipolar or bipolar operation ? ? ? ? ? current output ? ? ? ? ? internal feedback resistors ? ? ? ? ? high-reliability mil-std-883 models dac-hf series ultra-fast, 8/10/12-bit digital-to-analog converters figure 1. functional block diagram * see note in figure 1 input/output connections, dac-hf12b general description the dac-hf series of hybrid dac?s are ultra high-speed, current output devices. they incorporate state-of-the-art performance in a miniature package, achieving maximum output settling times of 25ns for the 8 and 10-bit models and 50ns for the 12-bit model. they can be used to drive a resistor load directly for up to 1v output or a fast operational ampifier (such as datel?s am-500) for higher voltage outputs with sub-microsecond settling times. a tapped feedback resistor and a bipolar offset resistor are included internally to give five programmable output voltage ranges with an external operational amplifier. the dac-hf design combines proven hybrid construction techniques with advanced circuit design to realize high-speed current switching. the design incorporates fast pnp current switches driving a low-impedance r-2r thin-film ladder network. the nichrome thin-film resistor network is deposited by electron beam evaporation on a low- capacitance substrate to assure high-speed performance. the resistors are then functionally trimmed by laser for optimum linearity. reference control circuit 23 ?15v supply 22 +15v supply 24 15 14 13 grounds 16 2k 2k 4k 18 19 17 20 bipolar offset bit 12 * 11 * 10 * 9 * 8 7 6 5 4 3 2 1 msb fast pnp current switches for dac-hf10b, pins 11 & 12 are no connection for dac-hf8b , pins 9 , 10 , 11 & 12 are no connection * 21 reference out (?10.05v0.05v) ?10v reference thin-film r-2r ladder network digital inputs lsb pin 20v range 10v range output reference in 12 11 10 9 8 7 6 5 4 3 2 1
dac-hf series ? ? description 8b 10b 12b inputs resolution, bits 8 10 12 coding, unipolar output straight binary coding, bipolar output offset binary input logic level, bit on ("1") +2.0v to +5.5v at +40 a input logic level, bit off ("0") 0v to +0.8v at ?2.6ma performance nonlinearity error, max. 0.012% t min to t max 0.024% differential nonlinearity error, max. 0.012% t min to t max 0.024% monotonicity guaranteed over oper. temp. range gain tempco, max. 20ppm/c offset tempco, bipolar, max. 10ppm/c of fsr ? zero tempco, max. 1.5ppm/c of fsr ? settling time, ns max. ? 25 25 50 power supply sensitivity 0.01%/% supply outputs output current range, unipolar 0 to +5ma output current range, bipolar 2.5ma output compliance voltage 1.2v output voltage ranges ? 0 to ?5v 0 to ?10v 2.5v 5v 10v output resistance 400 ohms 10% output capacitance 15pf output leakage current, all bits off 15na power requirements supply voltages 15v 0.5v positive quiescent current, max. 40ma 45ma 50ma negative quiescent current, max. 17ma 17ma 17ma physical environmental operating temperature range, case 0c to +70c (bmc) ?55c to +125c (bmm, 883) storage temperature range ?65c to +150c package type 24-pin ceramic ddip weight 0.22 ounces (6.3 grams) technical notes 1. proper operation of the dac-hf series converters is dependent on good board layout and connection practices. bypass supplies as shown in the connection diagrams. mount bypass capacitors close to the converter, directly to the supply pins where possible. 2. use of a ground plane is particularly important in high- speed d/a converters as it reduces high-frequency noise and aids in decoupling the digital inputs from the analog output. avoid ground loop problems by connecting all grounds on the board to the ground plane. the remainder of the ground plane should include as much of the circuit board as possible. 3. when the converter is configured for voltage output with an external operational amplifier, keep the leads from the converter to the output amplifier as short as possible. 4. the high-speed current switching technique used in the dac-hf series inherently reduces the amplitude and duration of large transient spikes at the output (?glitches?). the most severe glitches occur at half-scale, the major carry transition from 011 ? 1 to 100 ? 0 or vice versa. at this time, a skewing of the input codes can create a transition state code of 111 ? 1. the duration of the ?transition state code? is dependent on the degree of skewing, but its effect is dependent on the speed of the dac (an ultra-fast dac will respond to these brief spurious inputs to a greater degree than a slow dac). minimize the effects of input skewing by using a high- speed input register to match input switching times. the input register recommended for use with the dac-hf is easily implemented with two texas instruments sn74s174 hex d-type flip-flops. this register will reduce glitches to a very low level and ensure fast output settling times. 5. test the dac-hf using a low-capacitance test probe (such as a 10x probe). take care to assure the shortest possible connection between probe ground and circuit ground. long probe ground leads may pick up environmental e.m.i. causing artifacts on the scope display, i.e., signals that do not originate at the unit under test. 6. passive components used with the dac-hf may be as indicated here: 0.1 f and 1 f bypass capacitors should be ceramic type and tantalum type respectively; the 400 output load is a 0.1%, 10ppm/c, metal-film type; adjustment potentiometers are ceremet types; other resistors may be 10% carbon composition types. 7. output voltage compliance is 1.2v to preserve the linearity of the converter. in the bipolar mode, the dac-hf can be operated with no load to give an output voltage of 1.0v. in the unipolar mode, the load resistance must be less than 600 to give less than +1.2v output. the specified output currents of 0 to +5ma and 2.5ma are measured into a short circuit or an operational amplifier summing junction. absolute maximum ratings, all models functional specifications (typical at +25c and 15v supplies unless otherwise noted.) positive supply, pin 24 +18v negative supply, pin 22 ?18v digital input voltage, pins 1?12 +15v lead temperature (soldering, 10s) 300 c footnotes ? with external operational amplifier. ? fsr is full scale range, or the difference between minimum and maximum output values. ? full-scale current change to 1lsb with 400 load.
dac-hf series ? ? calibration procedure unipolar output current 1. connect the converter as shown in figure 2. 2. set all inputs low and adjust the zero adjust potentiometer for a reading of 0v at the output. 3. set all inputs high and adjust the gain adjust potentiometer for a reading of ?f.s. + 1lsb (see table 1). bipolar output current 1. connect the converter as shown in figure 3. 2. set all inputs low and adjust the offset adjust and load potentiometer for an output reading of +f.s. (see table 2). 3. set all inputs high and adjust the gain adjust potentiom- eter for an output reading of ?f.s. + 1lsb (see table 2). 1f + + bit 1 output i +15v bit 12 12 1 24 23 22 20 21 16 15 14 13 19 17 18 out 0.1f ?15v 1f 0.1f 100 offset adjust 100 gain adjust load (444 nominal) (for 0 to 0.5v fs) 200 370 figure 3. bipolar current output connections 2k feedback (10v range) bipolar offset 23 20 21 19 4k = 0.1% 18 400 , 10% ref out (?10v = 2%) 4k feedback (20v range) output ground 2k 2k 5ma 17 figure 4. equivalent output circuit analog output 0 to ?10v f.s. 0 to ?5v f.s. 0 to 1v f.s. input coding straight binary unipolar scale ?f.s. + 1lsb 1111 1111 1111 +0.9998v ?4.9988v ?9.9976v ?3/4f.s. 1100 0000 0000 +0.7500v ?3.7500v ?7.5000v ?1/2f.s. 1000 0000 0000 +0.5000v ?2.5000v ?5.0000v ?1/4f.s. 0100 0000 0000 +2.5000v ?1.2500v ?2.5000v ?1lsb 0000 0000 0001 +0.0002v ?0.0012v ?0.0024v 0 0000 0000 0000 0.0000v 0.0000v 0.0000v table 2. 12-bit bipolar output coding analog output input coding offset binary bipolar scale ?f.s. + 1lsb 1111 1111 1111 +0.4998v ?2.4988v ?4.9976v ?9.9951v ?1/2f.s. 1100 0000 0000 +0.1250v ?1.2500v ?2.5000v ?5.0000v ?1lsb 1000 0000 0001 +0.0002v ?0.0012v ?0.0024v ?0.0049v 0 1000 0000 0000 0.0000v 0.0000v 0.0000v 0.0000v +1/2f.s. 0100 0000 0000 ?0.1250v +1.2500v +2.5000v +5.0000v +f.s. ? 1lsb 0000 0000 0001 ?0.4998v +2.4988v +4.9976v +9.9951v +f.s. 0000 0000 0000 ?0.5000v +2.5000v +5.0000v +10.0000v 10v f.s. 5v f.s. 2.5v f.s. 0.5v f.s. table 3. programmable output range pin connections output voltage range feedback connections connect these pins together 0 to ?5v pin 19 pin 17 to pin 18 / pin 20 to pin 23 0 to ?10v pin 19 pin 20 to pin 23 2.5v pin 19 pin 17 to pin 18 / pin 20 to pin 18 5v pin 19 pin 20 to pin 18 10v pin 17 pin 20 to pin 18 in all programmable output ranges, pin 18 connects to external operational amplifier inverting input. table 1. 12-bit unipolar output coding figure 2. unipolar current output connections 1f + 100 2m + bit 1 output i +15v gain adjust bit 12 12 1 24 23 22 20 21 16 15 14 13 19 17 18 out 0.1f ?15v 1f 0.1f zero adjust 25k ?15v +15v 400 load (for 0 to +1v fs) 50nsec/div dac-hf with am-500, 5v ou tput full scale (10v) step 2v/div 50nsec/div 2v/div figure 5. voltage output waveforms
dac-hf series ? ? applications output typical settling step time to 1lsb 20v 2 s 10v 600ns 5v 400ns 0.200 max. (5.080) 0.235 max. (5.969) 0.600 0.010 (15.240) 0.80 max. (20.32) 0.100 typ. (2.540) 0.100 (2.540) 0.018 0.002 (0.457) 0.100 (2.540) 0.040 (1.016) 1.31 max. (33.27) 112 13 24 1.100 (27.940) 0 .190 max. (4.826) 0.010 (0.254) +0.002 ?0.001 seating plane 0.025 (0.635) dimension tolerances (unless otherwise indicated): 2 place decimal (.xx) 0.010 (0.254) 3 place decimal (.xxx) 0.005 (0.127) lead material: kovar alloy lead finish: 50 microinches (minimum) gold plating over 100 microinches (nominal) nickel plating output typical settling step time to 1lsb 20v 300ns 10v 200ns 5v 150ns figure 6. unipolar ultra-fast voltage output circuit figure 7. unipolar fast voltage output circuit mechanical dimensions inches (mm) ordering information
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8 9 operating model temp. range bits dac-hf8bmc 0 to +70c 8 dac-hf8bmm ?55 to +125c 8 dac-hf8/883 ? ?55 to +125c 8 dac-hf10bmc 0 to +70c 10 dac-hf10bmm ?55 to +125c 10 dac-hf10/883 ? ?55 to +125c 10 dac-hf12bmc 0 to +70c 12 dac-hf12bmm ?55 to +125c 12 dac-hf12/883 ? ?55 to +125c 12 usa: tucson (az), tel: (800) 547 2537, email: sales@cdtechno.com portland (or), tel: 971 206 2800, email: portland@cdtechno.com canada: toronto, tel: (905) 944 2850, email: toronto@cdtechno.com united kingdom: milton keynes, tel: +44 (0)1908 615232, email: mk@cdtechno.com france: montigny le bretonneux, tel: +33 (0)1 34 60 01 01, email: france@cdtechno.com germany: mnchen, tel: +49 (0)89-544334-0, email: ped.munich@cdtechno.com japan: tokyo, tel: 3-3779-1031, email: sales_tokyo@cdtechno.com osaka, tel: 6-6354-2025, email: sales_osaka@cdtechno.com website: www.cd4power.jp china: shanghai, tel: +86 215 027 3678, email: shanghai@cdtechno.com guangzhou, tel: +86 208 221 8066, email: guangzhou@cdtechno.com c&d technologies, inc. 11 cabot boulevard, mansfield, ma 02048-1151 u.s.a. tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 www.cd4power.com email: sales@cdtechno.com iso 9001 registered ds-0132c 6/2007 c&d technologies, inc. makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. the descriptions contained herein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. specifications are subject to change without notice.
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