1/11 february 2003 n output voltage range: 1.2 to 37v n output current in excess of 500 ma n line regulation typ. 0.01% n load regulation typ. 0.1% n thermal overload protection n short circuit protection n output transition safe area compensation n floating operation for high voltage applications description the lm217m/lm317m are monolithic integrated circuits in to-220 and dpak packages intended for use as positive adjustable voltage regulators. they are designed to supply until 500 ma of load current with an output voltage adjustable over a 1.2 to 37v range. the nominal output voltage is selected by means of only a resistive divider, making the device exceptionally easy to use and eliminating the stocking of many fixed regulators. lm217m lm317m medium current 1.2 to 37v adjustable voltage regulator schematic diagram to-220 dpak
lm217m/lm317m 2/11 absolute maximum ratings (*) re-boot is not guaranteed for t j 3 85c. thermal data connection diagram (top view) ordering codes (*) available in tape & reel with the suffix "-tr". test circuit symbol parameter2 value unit v i- v o input-output differential voltage 40 v p d power dissipation internally limited t opr operating junction temperature range (*) for lm217m -40 to 125 c for lm317m 0 to 125 t stg storage temperature range -55 to 150 c symbol parameter sot-82 sot-194 dpak to-220 unit r thj-case thermal resistance junction-case max 83c/w r thj-amb thermal resistance junction-ambient max 100 50 c/w type to-220 dpak (*) lm217m lm217mt LM217MDT lm317m lm317mt lm317mdt to-220 dpak
lm217m/lm317m 3/11 electrical characteristics of lm217m (refer to the test circuits, t j = - 40 to 125c, v i -v o =5v,i o = 100 ma, p d 7.5 w, unless otherwise specified). (*) cadj is connected between adjust pin and ground. electrical characteristics of lm317m (refer to the test circuits, t j = 0 to 125c, v i -v o =5v,i o = 100 ma, p d 7.5 w, unless otherwise specified). (*) cadj is connected between adjust pin and ground. symbol parameter test conditions min. typ. max. unit d v o line regulation v i -v o =3to40v t j = 25c 0.01 0.02 %/v 0.02 0.05 d v o load regulation v o 5v i o =10to500ma t j = 25c 5 15 mv 20 50 v o 3 5v i o =10to500ma t j = 25c 0.1 0.3 %/v o 0.3 1 i adj adjustment pin current 50 100 a d i adj adjustment pin current v i -v o =3to40v i o = 10 to 500 ma 0.2 5 a v ref reference voltage v i -v o =3to40v i o = 10 to 500 ma 1.2 1.25 1.3 v d v o /v o output voltage temperature stability 0.7 % i o(min) minimum load current v i -v o =40v 3.5 5 ma i o(max) maximum output current v i -v o 15 v 500 1000 ma v i -v o =40v, p d lm217m/lm317m 4/11 figure 1 : current limit figure 2 : minimum operating current figure 3 : basic adjustable regulator figure 4 : thermal resistance & maximum power dissipation vs p.c.b. copper length for dpak p dmax calculated for t a =50c.
lm217m/lm317m 5/11 application information the lm217m/lm317m provide an internal reference voltage of 1.25v between the output and adjustment terminals. these devices are used to set a constant current flow across an external resistor divider (see fig. 3), giving an output voltage v o of: v o =v ref (1 + r 2 /r 1 )+ i adj r 2 the devices were designed to minimize the term i adj (100a max) and to maintain it very constant in line and load changes. usually, the error term i adj r 2 can be neglected. to obtain the previous requirement, all the regulator quiescent current is returned to the output terminal, imposing a minimum load current condition. if the load is insufficient, the output voltage will rise. since the lm217m/lm317m devices are floating regulators and "see" only the input-to-output differential voltage, supplies of very high voltage with respect to ground can be regulated as long as the maximum input-to-output differential is not exceeded. furthermore, programmable regulators are easily obtained and, by connecting a fixed resistor between the adjustment and output, the devices can be used as a precision current regulator. in order to optimize the load regulation, the current set resistor r 1 (see fig. 3) should be tied as close as possible to the regulator, while the ground terminal of r 2 should be near the ground of the load to provide remote ground sensing. external capacitors (fig.5) normally no capacitors are needed unless the devices are situated far from the input filter capacitors; in which case an input bypass is needed. a 0.1f disc or 1f tantalum input bypass capacitor (c i ) is recommended to reduce the sensitivity to input line impedance. the adjustment terminal may be bypassed to ground to improve ripple rejection. this capacitor (cadj) prevents ripple from being amplified as the output voltage is increased. a 10f capacitor should improve ripple rejection of about 80db at 120hz in a 10v application. although the lm217m/lm317m devices are stable with no output capacitance like any feedback circuit, certain values of external capacitance can cause excessive ringing. an output capacitance (c o ) in the form of a 1f tantalum or 25f aluminium electrolytic capacitor on the output swamps this effect and insures stability. protection diodes (fig.5) when external capacitors are used with any ic regulator it is sometimes necessary to add protection diodes to prevent the capacitors from discharging through low current points into the regulator. figure 5 shows the lm217m/lm317m with the recommended protection diodes for output voltages in excess of 25v or high capacitance values (c 3 > 25f, c 2 > 10f). diode d1 prevents c 3 from discharging through the ic during an input short-circuit. the combination of diodes d1 and d2 prevents c 2 from discharging through the regulator during an input or output short-circuit. start-up block its not guaranteed the re-boot of the device when the junction temperature is over 85c.
lm217m/lm317m 6/11 figure 5 : voltage regulator with protection diodes figure 6 : slow turn-on 15v regulator figure 7 : current regulator 1.25v ??? r 1 v ref i o = ??? + i adj ? r 1
lm217m/lm317m 7/11 figure 8 : 5v electronic shut-down regulator figure 9 : digitally selected outputs (r 2 = sets maximum v o )
lm217m/lm317m 8/11 dim. mm. inch min. typ max. min. typ. max. a 4.40 4.60 0.173 0.181 c 1.23 1.32 0.048 0.051 d 2.40 2.72 0.094 0.107 d1 1.27 0.050 e 0.49 0.70 0.019 0.027 f 0.61 0.88 0.024 0.034 f1 1.14 1.70 0.044 0.067 f2 1.14 1.70 0.044 0.067 g 4.95 5.15 0.194 0.203 g1 2.4 2.7 0.094 0.106 h2 10.0 10.40 0.393 0.409 l2 16.4 0.645 l4 13.0 14.0 0.511 0.551 l5 2.65 2.95 0.104 0.116 l6 15.25 15.75 0.600 0.620 l7 6.2 6.6 0.244 0.260 l9 3.5 3.93 0.137 0.154 dia. 3.75 3.85 0.147 0.151 to-220 mechanical dat a p011c
lm217m/lm317m 9/11 dim. mm. inch min. typ max. min. typ. max. a 2.2 2.4 0.086 0.094 a1 0.9 1.1 0.035 0.043 a2 0.03 0.23 0.001 0.009 b 0.64 0.9 0.025 0.035 b2 5.2 5.4 0.204 0.212 c 0.45 0.6 0.017 0.023 c2 0.48 0.6 0.019 0.023 d 6 6.2 0.236 0.244 e 6.4 6.6 0.252 0.260 g 4.4 4.6 0.173 0.181 h 9.35 10.1 0.368 0.397 l2 0.8 0.031 l4 0.6 1 0.023 0.039 dpak mechani cal data 0068772-b
lm217m/lm317m 10/11 dim. mm. inch min. typ max. min. typ. max. a 180 7.086 c 12.8 13.0 13.2 0.504 0.512 0.519 d 20.2 0.795 n 60 2.362 t 14.4 0.567 ao 6.80 6.90 7.00 0.268 0.272 0.2.76 bo 10.40 10.50 10.60 0.409 0.413 0.417 ko 2.55 2.65 2.75 0.100 0.104 0.105 po 3.9 4.0 4.1 0.153 0.157 0.161 p 7.9 8.0 8.1 0.311 0.315 0.319 tape & reel dpak-ppak mechanical data
lm217m/lm317m 11/11 information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result f rom its use. no license is granted by implication or otherwise under any patent or patent rights of stmicroelectronics. specificati ons mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectronics. ? the st logo is a registered trademark of stmicroelectronics ? 2003 stmicroelectronics - printed in italy - all rights reserved stmicroelectronics group of companies australia - brazil - canada - china - finland - france - germany - hong kong - india - israel - italy - japan - malaysia - malt a - morocco singapore - spain - sweden - switzerland - united kingdom - united states. ? http://www.st.com
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