l272 january 1995 dual power operational amplifiers . output current to 1 a . operates at low voltages . single or split supply . large common-mode and differen- tial mode range . ground compatible inputs . low saturation voltage . thermal shutdown description the l272 is a monolithic integrated circuits in pow- erdip, minidip and so packages intended for use as power operational amplifiers in a wide range of ap- plications including servo amplifiers and power sup- plies, compacts disc, vcr, etc. the high gain and high output power capability pro- vide superior performance whatever an operational amplifier/power booster combination is required. powerdip (8 + 8) minidip ordering numbers : l272 (powerdip) L272M (minidip) l272d (so16 narrow) pin connections (top view) so16 (narrow) l272d L272M 1/10
block diagrams schematic diagram (one only) l272 L272M l272d l272 2/10
absolute maximum ratings symbol parameter value unit v s supply voltage 28 v v i input voltage v s v i differential input voltage v s i o dc output current 1 a i p peak output current (non repetitive) 1.5 a p tot power dissipation at: t amb = 80 c (l272), t amb = 50 c (L272M), t case = 90 c (l272d) t case = 75 c (l272) 1.2 5 w w t op operating temperature range (l272d) C 40 to 85 c t stg , t j storage and junction temperature C 40 to 150 c electrical characteristics (v s = 24v, t amb = 25 o c unless otherwise specified) symbol parameter test conditions min. typ. max. unit v s supply voltage 4 28 v i s quiescent drain current v o = v s 2 v s = 24v v s = 12v 8 7.5 12 11 ma ma i b input bias current 0.3 2.5 m a v os input offset voltage 15 60 mv i os input offset current 50 250 na sr slew rate 1v/ m s b gain-bandwidth product 350 khz r i input resistance 500 k w g v o. l. voltage gain f = 100hz f = 1khz 60 70 50 db db e n input noise voltage b = 20khz 10 m v i n input noise current b = 20khz 200 pa crr common mode rejection f = 1khz 60 75 db svr supply voltage rejection f = 100hz, r g = 10k w , v r = 0.5v v s = 24v v s = 12v v s = 6v 54 70 62 56 db v o output voltage swing i p = 0.1a i p = 0.5a 21 23 22.5 v v c s channel separation f = 1 khz; r l =10 w , g v = 30db v s = 24v v s = 6v 60 60 db d distortion f = 1khz, g v = 3 db, v s = 24v, r l = 0.5 % t sd thermal shutdown junction temperature 145 c thermal data symbol parameter powerdip so16 minidip unit r th j-case thermal resistance junction-pins max. 15 C * 70 o c/w r th j-amb thermal resistance junction-ambient max. 70 C 100 o c/w r th j-alumina thermal resistance junction-alumina max. C ** 50 C o c/w * thermal resistance junction-pin 4 ** thermal resistance junctions-pins with the chip soldered on the middle of an alumina supporting substrate measuring 15x 20mm; 0.65mm thickness and infinite heatsink. l272 3/10
figure 1 : quiescent current versus supply voltage figure 2 : quiescent drain current versus temperature figure 3 : open loop voltage gain figure 4 : output voltage swing versus load current figure 5 : output voltage swing versus load current figure 6 : supply voltage rejection versus frequency l272 4/10
figure 7 : channel separation versus frequency figure 8 : common mode rejection versus frequency application suggestion note in order to avoid possible instability occuring into fi- nal stage the usual suggestions for the linear power stages are useful, as for instance : - layout accuracy ; - a 100nf capacitor corrected between supply pins and ground ; - boucherot cell (0.1 to 0.2 m f + 1 w series) between outputs and ground or across the load. figure 9 : bidirectional dc motor control with m p compatible inputs figure 10 : servocontrol for compact-disc figure 11 : capstan motor control in video recorders l272 5/10
figure 12 : motor current control circuit. note : the input voltage level is compatible with l291 (5-bit d/a converter). figure 13 : bidirectional speed control of dc motors. 2r3 r1 for circuit stability ensure that r x > where r m = internal resistance of motor. r m v s 2r r1 the voltage available at the terminals of the motor is v m = 2 (v i ) + ? r o ? i m where ? r o ? = 2r x and i m is the motor current. l272 6/10
powerdip 16 package mechanical data dim. mm inch min. typ. max. min. typ. max. a1 0.51 0.020 b 0.85 1.40 0.033 0.055 b 0.50 0.020 b1 0.38 0.50 0.015 0.020 d 20.0 0.787 e 8.80 0.346 e 2.54 0.100 e3 17.78 0.700 f 7.10 0.280 i 5.10 0.201 l 3.30 0.130 z 1.27 0.050 l272 7/10
minidip package mechanical data dim. mm inch min. typ. max. min. typ. max. a 3.32 0.131 a1 0.51 0.020 b 1.15 1.65 0.045 0.065 b 0.356 0.55 0.014 0.022 b1 0.204 0.304 0.008 0.012 d 10.92 0.430 e 7.95 9.75 0.313 0.384 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 f 6.6 0.260 i 5.08 0.200 l 3.18 3.81 0.125 0.150 z 1.52 0.060 l272 8/10
so16 narrow package mechanical data dim. mm inch min. typ. max. min. typ. max. a 1.75 0.069 a1 0.1 0.25 0.004 0.009 a2 1.6 0.063 b 0.35 0.46 0.014 0.018 b1 0.19 0.25 0.007 0.010 c 0.5 0.020 c1 45 (typ.) d 9.8 10 0.386 0.394 e 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 8.89 0.350 f 3.8 4.0 0.150 0.157 l 0.4 1.27 0.150 0.050 m 0.62 0.024 s8 (max.) l272 9/10
information furnished is believed to be accurate and reliable. however, sgs-thomson microelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of t hird part ies which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of sgs-thomson microelectronics. specifica- tions mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information pre- viously supplied. sgs-thomson microelectronics products are not authorized for use as critical comp onents in life support dev ices or systems without express written approval of sgs-thomson microelectronics. ? 1995 sgs-thomson microelectronics - all rights reserved sgs-thomson microelectronics group of companies australia - brazil - france - germany - hong kong - italy - japan - korea - malay sia - malta - morocco - the netherlands - s ingapore - spain - sweden - switzerland - taiwan - thaliand - united kingdom - u.s.a. l272 10/10
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