innovation and ex c ell e n c e ? ? figure 1. simpli ed schematic new datel, inc., mans? eld, ma 02048 (usa) tel: (508)339-3000, (800)233-2765 fax: (508)339-6356 email: sales@datel.co m internet: www.datel.com +load +load fault ?load ?load buffer amplifier +5 volt supply +5 volt return control voltage in (+) control voltage in (?) isolation amplifier isolated dc/dc converter isolated dc/dc converter amplifier current driver error detection + ? the DTL22A is an isolated (500vdc), near-ideal (z in = z out 10m ? ), analog/ voltage-controlled current sink. its 0-20a output/load current is straightforwardly "programmed" by applying a 0-10v input. the control signal can be generated by circuits as simple as the wiper of a trimpot or as sophisticated as programmable logic controllers (plc?s) or analog-output computer i/o boards (d/a boards). the DTL22A supports any combination of i out = 0-20 amps and v out = 2.5-50 volts. its thermally ef? cient, metal package, when properly heat sunk, can dissipate output/load power up to 100 watts. the easy-to-use DTL22A is an excellent building block for low-cost, fully ? exible, power-supply (ac/dc or dc/dc) or power-component (mosfet?s, diodes, etc.) test and burn-in applications. it is accurate (5ma offset error, 1% overall accuracy), fast (200sec full-scale step response), and capable of impressive resolution. if it is controlled with a 12-bit, 0-10v d/a converter, for example, one lsb (least signi? cant bit) of the d/a corresponds to a 5ma change in the DTL22A?s output/load current. the DTL22A is packaged in a small (2" x 2" x 0.5"), thermally ef? cient metal package incorporating an aluminum baseplate with threaded inserts. it is powered by a single +5v supply and draws a mere 150ma. the DTL22A has an output compliance voltage of 2.5-50 volts. should the output/load voltage drop below the 2.5v required for proper biasing, an internal monitoring circuit activates the DTL22A?s output fault line. see datel?s DTL22A-lc for compliance voltages as low as 0.6v. the DTL22A and other electronic loads, controller boards, and software from datel are outstanding building-block components for power-supply burn-in and test systems. they are extremely reliable, cost-effective solutions that enable you to quickly con? gure impressively accurate systems. features applications 0-10v input/control voltage 0-20a output/load current 2.5-50v output compliance voltage 0-100w output/load power 10m ? output impedance 500vdc isolation ?% accuracy under all conditions 200?ec full-scale step response 2" x 2", shielded metal package operate in parallel for higher power power-supply test and characterization static/dynamic power-supply burn-in power-resistor substitution real-time load simulation capacitor discharge testing dtl series DTL22A model voltage-controlled, 20 amp 100 watt, electronic loads
dtl series pin function p51 pin function p51 1 +5 volt supply 7 control voltage in (?) 2 +5 volt return 8 ?load 3 fault 9 ?load 4 no pin 10 +load 5 control voltage in (+) 11 +load 6 no pin performance speci cations and ordering guide ? part number structure mechanical specifications input output dtl 22 datel electronic load voltage range: 22 = 2.5 to 50v a a-series high reliability temperature derating 11 8 9 10 1 2 4 3 5 6 7 metal case aluminum baseplate 2.00 (50.80) 2.00 (50.80) 0.20 min (5.08) 1.20 (30.48) 6 eq. sp. @ 0.200 (5.08) 1.800 (45.72) 1.640 (41.66) 1.640 (41.66) 0.50 (12.70) 0.060 0.002 dia. (1.524 0.051) 0.040 0.002 dia. (1.016 0.051) #4-40 clear thru (typ. 4 pl) bottom view 0.10 (2.54) 0.08 (2.03) 0.22 (5.59) 0.40 (10.16) i/o connections contact datel for heat sink information. the horizontal axis of the above chart references the temperature of the DTL22A?s aluminum baseplate. the device can continually dissipate up to 100 watts if the baseplate is maintained at or below +50c. at +25c ambient temperature, with no heat sink or supplemental air ? ow, the DTL22A can reliably dissipate a continuous 10 watts. 2 case c24 control compliance voltage impedance current resolution voltage power package model (volts) (minimum) (amps) (ma) ? (volts) ? (watts) (case, pinout) DTL22A 0 to +10 10m ? 0-20 5 2.5-50 0-100 c24, p51 ? typical at t a = +25c with nominal +5v supply voltage, unless noted. ? listed resolution (5ma) is for a typical application in which the DTL22A is controlled by a voltage generated by a 12-bit d/a converter with a 0-10v output range. one lsb (least signi? cant bit) of the d/a corresponds to 0.0244% (1/4096) of full scale (20 amps), which equals approximately 5ma. ? for proper operation, the unit's output/load voltage must remain within this range. voltages greater than the listed maximum can damage the device. voltages less than the minimum provide insuf? cient bias for the output stage and will result in unpredictable or no operation. see output compliance voltage and the fault line for details. output power/load (watts) baseplate temperature ( c) 100 90 80 70 60 50 40 30 20 10 010 2030405060708090100 100 watt, voltage-controlled electronic load
DTL22A model input control voltage 0-10 volts impedance 10m ? , minimum output transfer function i out (amps) = 2v in (volts) current: range 0-20 amps resolution ? 0.025%fs (5ma) offset error ? 5ma, maximum gain error 0.25%, maximum absolute accuracy ? 1%, maximum voltage ? 2.5-50 volts power ? 0-100 watts impedance 10m ? , minimum isolation voltage: analog input to load 500vdc, minimum +5v power to input or load 500vdc, minimum any pin to case 500vdc, minimum isolation resistance 100m ? , minimum fault logic levels: logic "1" (@ 150a) +3.5 volts, minimum logic "0" (@ 1.6ma) +0.4 volts, maximum dynamic performance output slew rate 0.4a/sec, minimum output settling time ? 200sec dynamic loading: ? 10ma to 20a 5khz 0 to 20a 1khz power requirements power supply range (+v cc , pin 1) +4.75-5.25 volts (+5v nominal) power supply current 110ma typ., 150ma max. environmental operating temperature ? ?25 to +85c storage temperature ?40 to +85c humidity (non-condensing) to 95% altitude above sea level 10,000 feet physical dimensions 2" x 2" x 0.5" (51 x 51 x 12.7mm) shielding 6-sided case material tin-plated steel shell with aluminum baseplate pin material brass, solder coated mounting holes through-hole spacers, #4-40 clearance weight 1.9 ounces (54 grams) ? listed resolution (5ma) is for a typical application in which the DTL22A is controlled by a voltage generated by a 12-bit d/a converter with a 0-10v output range. one lsb (least signi? cant bit) of the d/a corresponds to 0.0244% (1/4096) of full scale (20 amps), which equals approximately 5ma. ? offset error is de? ned as the current sunk/sourced by the DTL22A?s output, under any output-voltage conditions, when the applied control voltage is 0 volts. ? applies over all ranges/combinations of speci? ed output current, load voltage, output power, operating temperature and v cc . ? for proper operation, the DTL22A's output voltage must remain within the range listed. voltages greater than the listed maximum can damage the device. voltages less than the listed minimum provide insuf? cient bias for the output stage and will result in unpredictable or no operation. see ouput compliance voltage and the fault line for details. ? the DTL22A can achieve its maximum output/load power only when its baseplate temperature is properly maintained. see temperature derating. ? speci? ed for the full-scale step from 10ma to 20 amps settling to 1% (200ma) of ? nal value. a minimal loading of 10ma is recommended to achieve the fastest dynamic response. ? baseplate temperature. see note 5 and temperature derating. supply voltage (+v cc , pin 1) ?0.5 to +5.5 volts input voltage (pin 5 ) ?0.5 to 15 volts output reverse-polarity protection no protection output overvoltage protection no protection output undervoltage protection yes (see fault line) case temperature +85c storage temperature (ambient) ?40 to +85c lead temperature (soldering, 10 sec.) +300c absolute maximum ratings these are stress ratings. exposure of devices to any of these conditions may adversely affect long-term reliability. proper operation under conditions other than those listed in the performance/functional speci? cations table is not implied. technical notes 3 overview the DTL22A is an analog programmable (0 to +10v control) current sink. it?s output/load current range is 0 to 20 amps over a compliance voltage range of 2.5 to 50 volts and an output/load power range of 0 to 100 watts. the device?s transfer function is as follows: iout (amps) = 2v in (volts) examples: control v in = 1 volt, i out = 2 amps control v in = 10 volts, i out = 20 amps in a typical power-supply test or burn-in application, the "positive" output and "return" pins of the device under test (dut) are connected to the DTL22A?s +load (pins 10 and 11) and ?load (pins 8 and 9) outputs. 100 watt, voltage-controlled electronic load performance/functional speci cations typical @ t a = +25c with nominal +5v supply voltage, unless noted.
datel makes no representation that the use of its products in the circuits described herein, or the use of other technical info rmation 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. speci cations are subject to change without notice. the datel logo is a registered datel, inc. trademark. datel (uk) ltd. tadley, england tel: (01256)-880444 datel s.a.r.l. montigny le bretonneux, france tel: 01-34-60-01-01 datel gmbh mnchen, germany tel: 89-544334-0 datel kk tokyo, japan tel: 3-3779-1031, osaka tel: 6-6354-2025 datel, inc. 11 cabot boulevard, mans eld, ma 02048-1151 tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 internet: www.datel.com email: sales@datel.com ds-0497 5/01 iso 9001 registered innovation and ex c ell e n c e ? ? output compliance voltage and the fault line for proper operation, the DTL22A?s output/load voltage must always be between 2.5 and 50 volts. the device cannot be used to directly load extremely low-voltage (such as 1.5v or 1.8v) power components or to simulate a true short circuit (0 volts). voltages greater than 50v can damage the device. voltages <2.5v will result in insuf cient biasing of the output current source and consequently unpredictable or no operation. accordingly, we have installed an internal output/load-voltage monitoring circuit. if the output/load voltage drops below 2.5v and the DTL22A?s output is at risk of becoming disabled, the fault line activates. the fault line is an active-low function with an open-collector output (internal 10k pull-up resistor to +5v). under normal conditions, its output is high (logic "1"). under fault conditions (v out < 2.5v), its output drops to a logic "0." there is no output/load-voltage monitoring circuit for voltages greater than 50v, and operation above 50v can damage the device. an "offset supply" can be inserted between the DTL22A?s ?load output (pins 8 and 9) and the power device under test (dut) to "translate" the DTL22A?s 47.5v output/load voltage range. the offset supply must have adequate current capabilities and be connected with the polarities indicated in figure 2 below. under no circumstances should the voltage across the DTL22A?s output be allowed to experience a polarity reversal. if a 5v/20a offset supply is inserted as shown, the range of dut voltages will be ?2.5 to +45 volts. such a con guration can be used for true short-circuit testing. a mechanical relay can be used to short the outputs of the dut while the offset supply ensures the DTL22A always sees at least 5 volts across its outputs. thermal considerations the DTL22A can reliably handle 100w loads if its aluminum baseplate tem- perature is maintained at or below +50c. with no heat sinking or auxiliary cooling, the device can only handle loads up to 10 watts. please refer to the temperature derating curve for additional information. datel?s electronic load applications engineers can assist you in developing heat-sink solutions for your higher-power DTL22A applications. contact us for details about our dtl-hs100d12 heat sinks. figure 2. an "offset supply" enables true short-circuit testing 4 constant-resistance application the DTL22A operates as a constant-current electronic load in its typical con guration. a constant-resistance mode of operation can be achieved as follows: the DTL22A has a high-impedance, isolated analog input that permits the inputs to be connected directly across the load. the DTL22A sinks 20 amps for a 10 volt full-scale input or i = 2 v in . if you make v in = v load , (the voltage across the load), then r = v load /i = v load / (2 v load ) = 0.5 ohms. consequently, the load looks like a 0.5 ohm resistor. furthermore, if you make v in = k v load by connecting a potentiometer or resistive divider across the load, then r = v load / (2 k v load ) = 0.5/k. adjusting the potentiometer effectively gives you an adjustable power resis- tor. at k = 0.5, r = 1 ohm; at k = 0.25, r = 2 ohms, etc. the only limitations you must observe are the maximum load voltage (50v) and the maximum100 watt power dissipation. a multiplying digtal-to-analog converter or a digital potentiometer can also be used to effectively make a program- mable resistance. technical notes +load DTL22A ?load 9 8 11 10 5v ? ? + + dut short circuit relay dtl series 100 watt, analog-controlled electronic load
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