dtl series DTL2A model 100 watt, digitally programmable serial-input, electronic loads mdc_DTL2A.bo1 page 1 of 5 www.murata-ps.com www.murata-ps.com technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 features applications figure 1. simpli ed schematic ) 3 / , ! 4 % $ $ # $ # # / . 6 % 2 4 % 2
" ) 4 $ ! $ ! 4 ! , ! 4 # ( ! - 0 , ) & ) % 2 ! . $ # 5 2 2 % . 4 3 % . 3 / 2 , / ! $ , / ! $ n , / ! $ n , / ! $ # / . 4 2 / , 3 4 2 / " % # 3 # , / # + # , + ) . 0 5 4 " 5 & & % 2 3 / 0 4 / ) 3 / , ! 4 / 2 3 3 % 2 ) ! , $ ! 4 ! ) . 0 5 4 3 $ ) , ! 4 # ( $ ! 4 ! , $ ' 2 / 5 . $ 6 3 5 0 0 , 9 5 . $ % 2 6 / , 4 ! ' % $ % 4 % # 4 ) / . 0 / 7 % 2 $ % 6 ) # % 5 . $ % 2 4 % 3 4 & ! 5 , 4 datel?s new DTL2A is an optically isolated, digitally programmable, serial-input, electronic load. it is essentially a digitally controlled current source that can sink currents from 0 to 20 amps, at loading voltages from 2.5 to 50 volts, up to a maximum power of 100 watts. the DTL2A is packaged in a thermally ef? cient, 2" x 2" x 0.5" metal package that incorporates an aluminum baseplate with through-hole spacers for easy pcb mounting and/or external heat-sink attachment. the DTL2A accepts a serialized, 12-bit, cmos/ttl-compatible, digital input word easily generated by any standard digital i/o card. the DTL2A buffers and then opti- cally isolates (500vdc) the digital input data before storing it in a register and present- ing it to an on-board, 12-bit, digital-to-analog (d/a) converter. the d/a output drives a near-ideal (10m minimum output impedance), voltage-controlled current source. one lsb (least signi? cant bit) of the d/a converter corresponds to a 5ma increment (0.025% of 20a) in load current. the DTL2A features a max. 5ma offset error and a max. 0.1% gain error. it has an impressive full-scale step response time of 100sec and can be operated dynamically at update rates up to 20khz. powered by a single +5v supply, the DTL2A draws a mere 150ma (maximum). while operating in the constant-current mode up to 20 amps (100w max. power), the output compliance voltage of the DTL2A is 2.5 to 50 volts. should the output/load voltage drop below the 2.5v minimum required for proper biasing, an internal monitoring circuit activates the DTL2A's output fault line. see datel?s DTL2A-lc for compliance voltages as low as 0.6v. DTL2A?s 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 an extremely reliable, cost-effective solution that enables you to quickly con? gure impressively accurate systems. 12-bit, optically isolated (500vdc), cmos/ttl-compatible serial input 0-20 amp output in 5ma increments 10m minimum output impedance output voltage to 50 volts output power to 100 watts ?ma offset error; ?.1% gain error 100?ec full-scale step response update rates to 20khz operate in parallel for higher power miniature, 2" x 2" metal package static/dynamic power-supply burn-in power-supply test and characterization battery capacity testing current-source testing capacitor discharge testing real-time load simulation
dtl series DTL2A model 100 watt, digitally programmable serial-input, electronic loads mdc_DTL2A.bo1 page 2 of 5 technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 www.murata-ps.com performance speci cations and ordering guide ? part number structure mechanical specifications compliance resolution logic current resolution voltage power package model (bits) compatibility (amps) (ma) ? (volts) ? (watts) (case, pinout) DTL2A 12 cmos/ttl ? 0-20 5 2.5-50 0-100 c24, p31 input output dtl 2 datel electronic load voltage range: 2 = 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) pin function p31 pin function p31 1 fault 7 control strobe (cs) 2 ground 8 ?load 3 +5 volt supply 9 ?load 4 latch data (ld) 10 +load 5 serial data in (sdi) 11 +load 6 clock (clk) i/o connections contact datel for heat sink information. output power/load (watts) baseplate temperature ( c) 100 90 80 70 60 50 40 30 20 10 010 203040506070809010 0 the horizontal axis of the above chart references the temperature of the DTL2A?s alumi- num 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 DTL2A can reliably dissipate a continuous 10 watts. case c24 ? typical at t a = +25c with nominal +5v supply voltage unless noted. ? the smallest increment/decrement in output current is de? ned by one lsb (least signi? cant bit) of the 12-bit digital input word. one lsb is equal to full scale (fs) divided by 4096 which corresponds to 0.0244% of 20a or 4.88ma. ? 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. ? see performance/functional speci? cations for details.
dtl series DTL2A model 100 watt, digitally programmable serial-input, electronic loads mdc_DTL2A.bo1 page 3 of 5 technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 www.murata-ps.com digital inputs/outputs logic compatibility (pins 1, 4-7) cmos/ttl input logic levels: logic "1" +2 volts, minimum logic "0" +0.8 volts, maximum input logic loading: logic "1" (i ih @ v ih = 5 volts) 20a, maximum logic "0" (i il @ v il = 0 volts) ?0.6ma, maximum output logic levels: logic "1" (@ 150a) +3.5 volts, minimum logic "0" (@ 1.6ma) +0.4 volts, maximum timing see timing diagram output current: range 0-20 amps resolution ? 0.024%fs (4.88ma) accuracy ? 1%, maximum voltage range ? 2.5-50 volts power range 0-100 watts impedance 10m , minimum offset error ? 5ma, maximum gain error 0.1%, maximum isolation voltage: digital inputs/output to load 500vdc, minimum any pin to case 500vdc, minimum isolation resistance 100m , minimum dynamic performance output slew rate 10a/sec, minimum output settling time ? 100sec digital input update rate to 20khz power requirements power supply range (+v cc , pin 3) +4.75-5.25 volts (+5v nominal) power supply current 110ma typ., 150ma max. environmental operating temperature ? ?40 to +100c (case) storage temperature ?40 to +125c (ambient) 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 (connected to pin 2) 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) ? the smallest increment/decrement in output current is de? ned by one lsb (least signi? cant bit) of the 12-bit digital input word. one lsb is equal to full scale (fs) divided by 4096 which corresponds to 0.0244% of 20a or 4.88ma. ? 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 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. ? offset error is de? ned as the current sunk/sourced by the DTL2A?s output, under any output voltage conditions, when the digital input word is all "0's." ? full scale step (20 amps) settling to within 5ma of its ? nal value. ? see temperature derating. ? applies over all speci? ed ranges/combinations of load voltage/current, operating temperature, and v cc . power supply voltage (+v cc , pin 3) ?0.5 to +5.5 volts digital input voltag e (pins 4-7) ?0.5 to +5.5 volts output reverse-polarity protection no protection output overvoltage protection no protection output undervoltage protection yes (see fault line) case temperature +105c storage temperature (ambient) ?40 to +125c 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. overview the DTL2A is a digitally programmable, cmos/ttl-compatible, serial-input current sink. it?s output/load current range is 0 to 20 amps (in 4.88ma increments), 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 digital i/o coding is straight binary (see table below). a digital input of all "0?s" forces a load current of 0 amps. a digital input of all "1?s" forces a load current of 19.995 amps. in a typical power-supply test or burn-in application, the output pins of the device under test (dut) are connected to the DTL2A?s +load (pins 10 and 11) and ?load (pins 8 and 9) outputs. the DTL2A?s operation is controlled by its four digital input lines (serial data in, clock, latch data and control strobe). technical notes msb lsb DTL2A 1111 1111 1111 19.995 1100 0000 0000 15.000 1000 0000 0000 10.000 0111 1111 1111 9.995 0100 0000 0000 5.000 0010 0000 0000 2.500 0000 0000 0001 0.005 0000 0000 0000 0.000 serial input data word load current (amps) mapping of the serial-input data to load current performance/functional speci cations typical @ t a = +25c with nominal +5v supply voltage, unless noted.
dtl series DTL2A model 100 watt, digitally programmable serial-input, electronic loads mdc_DTL2A.bo1 page 4 of 5 technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 www.murata-ps.com serial data following initialization, the 12-bit digital word representing the desired output current is applied to the sdi pin. the serial data should appear starting with the most signi? cant bit (msb, bit 1, d11) and ending with the least signi? cant bit (lsb, bit 12, d0). with each data bit present and stable on the sdi line, the clk must be toggled through a low-to-high transition to register that bit. twelve rising clock edges, at rates up to 500khz, are required to clock all 12 digital bits into the DTL2A?s input register. latching data and presenting it to the d/a after loading the lsb, the serial data word is latched by bringing the control strobe (pin 7) high and then toggling the latch data pin (pin 4) through a high-low-high sequence. approximately 100sec later, the output current will settle to its ? nal desired value. software: c language the following steps describe a typical timing sequence when using the DTL2A?s 4 digital inputs and a programming language such as c. using 4 bits of a typical 8-bit port, assign bit_0 to the control strobe (cs, pin 7), bit_1 to latch data (ld, pin 4), bit_2 to serial data in (sdi, pin 5), and bit_3 to the clock (clk, pin 6). 1. initialize with control strobe, latch data, and clock high: bit_0 = 1, bit_1 = 1, bit_2 = x (don?t care), bit_3 = 1 2. bring the control strobe low. bit_0 = 0 3. apply the msb (d11) of the serial data word to serial data in. bit_2 = 0 or 1 4. toggle the clock high-low-high. bit_3 = 1 to 0 to 1 5. apply d10 of the serial data word to serial data in. bit_2 = 0 or 1 6. toggle the clock high-low-high. bit_3 = 1 to 0 to 1 7. repeat the process for remaining data bits d9 through d0. 8. drive the control strobe high. bit_0 = 1 9. toggle the latch data input high-low-high. bit_1 = 1 to 0 to 1. output compliance voltage and the fault line for proper operation, the DTL2A?s output/load voltage must always be between 2.5 and 50 volts. the device cannot be used to directly load low- voltage, e.g. 1.8v or 2.5v, 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 DTL2A?s output is at risk of becoming disabled, the fault line activates. the fault line is an optically isolated, active-low function with an open- collector output (internal 10k pull-up resistor to +5v). under normal condi- tions, 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 DTL2A?s ?load output (pins 8 and 9) and the power device under test (dut) to "translate" the DTL2A?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 DTL2A?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 DTL2A always sees at least 5 volts across its outputs. thermal considerations the DTL2A can reliably handle 100w loads if its case temperature 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 applica- tions engineers can assist you in developing heat-sink solutions for your higher-power DTL2A applications. please contact us for details. initialization preparing the DTL2A to accept new digital data is accomplished by applying logic "1's" to control strobe (cs, pin 7), latch data (ld, pin 4) and clock (clk, pin 6) with all signals present and stable for a minimum of 1sec. during this interval, it does not matter whether or not data is present on the serial data in (sdi, pin 5) line. +load DTL2A ?load 11 10 9 8 5v ? ? + + dut short circuit relay figure 2. an "offset supply" enables true short-circuit testing
dtl series DTL2A model 100 watt, digitally programmable serial-input, electronic loads mdc_DTL2A.bo1 page 5 of 5 murata power solutions, 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 her ein do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. speci cations are subject to cha nge without notice. ? 2009 murata power solutions, inc. usa: mans eld (ma), tel: (508) 339-3000, email: sales@murata-ps.com canada: toronto, tel: (866) 740-1232, email: toronto@murata-ps.com uk: milton keynes, tel: +44 (0)1908 615232, email: mk@murata-ps.com france: montigny le bretonneux, tel: +33 (0)1 34 60 01 01, email: france@murata-ps.com germany: m?nchen, tel: +49 (0)89-544334-0, email: munich@murata-ps.com japan: tokyo, tel: 3-3779-1031, email: sales_tokyo@murata-ps.com osaka, tel: 6-6354-2025, email: sales_osaka@murata-ps.com china: shanghai, tel: +86 215 027 3678, email: shanghai@murata-ps.com guangzhou, tel: +86 208 221 8066, email: guangzhou@murata-ps.com singapore: parkway centre, tel: +65 6348 9096, email: singapore@murata-ps.com murata power solutions, inc. 11 cabot boulevard, mans eld, ma 02048-1151 u.s.a. tel: (508) 339-3000 (800) 233-2765 fax: (508) 339-6356 www.murata-ps.com email: sales@murata-ps.com iso 9001 and 14001 registered technical enquiries email: sales@murata-ps.com, tel: +1 508 339 3000 www.murata-ps.com 03/20/09 figure 3. DTL2A timing diagram clk ? ? 500 khz t in 1 ? ? sec t cl = t ch 1 ? ? sec t css 1 ? ? sec t csh 1 ? ? sec t ld1 2 ? ? sec t ld2 2 ? ? sec t ldw 2 ? ? sec t ds 0.5 ? ? sec t dh 0.5 ? ? sec timing min. typ. max. units sdi t dh t ds t css t in t cl t ch t csh t ld2 t ld1 t ldw d11 d10 d9 d8 d7 d6 d5 d4 d2 d3 d1 d0 clk cs ld
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