date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation spx2941 solved by tm 1a low dropout voltage regulator description features adjustable output down to 1.25v low quiescent current guaranteed 1.5a peak output current low dropout voltage of 280mv @ 1a extremely tight load and line regulation extremely fast transient response reverse-battery protection internal thermal and current limit protection zero current shutdown standard to-220 and to-263 packages figure 1. adjustable output linear regulator the spx2941 is a 1a, accurate voltage regulator with a low drop out voltage of 280mv(typ.) at 1a. these regulators are specifically designed for low voltage applications that require a low dropout voltage and a fast transient response. they are fully fault protected against over-current, reverse battery, and positive and negative voltage transients. the spx2941 is offered in 5-pin to-220 & to-263 packages. for a 3a version, refer to the spx29300 data sheet. spx2941 v out v in gnd adj 4 2 3 5 1 r1 r2 10 + f 6.8 + f + + en typical applications circuit now available in lead free packaging applications powering vga & sound card lcd monitors usb power supply power pc supplies smps post-regulator high efficiency linear power supplies battery charger portable instrumentation constant current regulators adjustable power supplies 1 2 3 4 5 spx2941 5 pin to-263 v in gnd v out adjust enable adjustable output, fast response
2 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation absolute maximum ratings lead temperature (soldering, 5 seconds) ................260 c storage temperature range........................-65 c to +150 c parameter conditions min. typ. max unit reference voltage adjustable version only 1.228 1.240 1.252 v 1.215 1.265 adjust pin bias current 40 80 v 120 reference voltage (n ote 4) 20 ppm/ c temperature coefficient adjust pin bias current 0.1 na/ c temperature coefficient line regulation i out =10ma, (v out +1v) ) v in ) 16v 0.2 1.0 % load regulation v in =v out +1v, 10ma ) i out ) i full 0.3 1.5 % dropout voltage (note1) i out =100ma 70 200 mv (except 1.8v version) i out =1a 280 550 ground current (note3) i out =750ma, v in =v out +1v 12 25 ma i out =1a 18 ground pin current at v in =0.1v less than specified v out , 1.2 ma dropout i out =10ma current limit v out =0v (note2) 1.5 2.2 a output noise voltage 10hz to 100khz, i out =100ma, c l =10 + f 400 + v rms c l =33 + f 260 input logic voltage low (off) v in <10v 0.8 v high (on) 2.4 enable input pin current v en =16v 100 600 + a 750 v en =0.8v 1 + a 2 regulator output current (n ote 5) 10 + a in shutdown 500 thermal resistance to-220 junction to case, at tab 3 c/w junction to ambient 29.3 to-263 junction to case, at tab 3 c/w junction to ambient 31.2 v in =v out + 1v, i out =10ma, c in =6.8 + f, c out =10 + f, t a = 25 c, unless otherwis specified. the boldface applies over the junction temperature range. adjustable versions are set at +5.0v. operating junction temperature range......-40 c to +125 c input supply voltage (n ote 6) .... .....................................16v electrical characteristics n ote 1: dropout voltage is defined as the input to output differential at which the output voltage drops to 99% of its nominal value. n ote 2: v in =v out(nominal) +1v; for example, v in =4.3v for a 3.3v regulator. employ pulse-testing procedures to minimize temperature rise. n ote 3: ground pin current is the regulator quiescent current. the total current drawn from the source is the sum of the load and ground currents. n ote 4: thermal regulation is defined as the change in the output voltage at a time t after a change in power dissipation is applied, excluding load or line regulation effects. n ote 5: v en ) 0.8v and v in ) 16v, v out = 0. n ote 6: maximum positive supply voltage of 20v must be of limited duration ( <100ms) and duty cycle (<1%). the maximum continuous supply voltage is 16v. n ote 7: v ref ) v out ) (v in -1), 2.5v ) v in ) 16v, 10 ma ) i c ) i fl , t j < t jmax . figure 2. spx2941 block diagram block diagram reference thermal shutdown en in out adj gnd o.v i limit 28v r1* r2* 1.240v + -
date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation ref erence ther ma l shutdo wn en in out adj gnd o. v i limit 28v r1* r2* 1.240v + - part number .................... accuracy ... output voltage ...................... package spx2941t5 ............................ 3% ........................ adj ............................. 5 lead to-263 spx2941t5/tr ...................... 3% ........................ adj ............................. 5 lead to-263 spx2941u5 ........................... 3% ........................ adj ............................. 5 lead to-220 package pinouts ordering information to-263-5 package (t5) top view 4 5 321 to-220-5 package (u5) top view 1 2 3 4 5 v in gnd v out 1) 3) 4) 5) 2) enable adjust spx2941 available in lead free packaging.to order add "-l" suffix to part number. example: spx2941t5/tr = standard; spx2941t5-l/tr = lead free /tr = tape and reel pack quantity is 500 for to-263-5. note: tab is internally connected to gnd block diagram figure 2. spx2941 block diagram
4 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation typical performance characteristics figure 3. line regulation for 3.3v device figure 4. load regulation for 3.3v device figure 7. ground current vs load current in dropout figure 8. dropout voltage vs load current for 3.3v device figure 5. ground current vs load current for 3.3v device figure 6. ground current vs input current 3.320 3.315 3.310 3.305 3.300 3.295 3.290 3.285 3.280 4 6 8 10 12 14 16 v in (v) v out (v) 3.3v device il = 10ma cl = 10 + f 3.310 3.305 3.300 3.295 3.290 3.285 3.280 il (a) v out (v) 0.00 0.25 0.50 0.75 1.00 1.25 1.50 3.3v device v in = 4.3v cl = 10 + f 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0.0 il (a) ignd (ma) 0.00 0.25 0.50 0.75 1.00 1.25 1.50 3.3v device v in = 4.3v cl = 10 + f 300 280 260 240 220 200 180 4 6 8 10 12 14 16 v in (v) ignd ( + a) 3.3v device il = 10ma cl = 10 + f 100 90 80 70 60 50 40 30 20 10 0 il (a) ignd (ma) 0.00 0.25 0.50 0.75 1.00 1.25 1.50 3.3v device v in = 3.2v cl = 10 + f 600 500 400 300 200 100 0 il (a) v dropout (mv) 0.00 0.25 0.50 0.75 1.00 1.25 1.50 3.3v device cl = 10 + f
date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation figure 9. ground current vs temperature at i load =10ma figure 10. output voltage vs temperature at i load =10ma figure 11. ground current vs temperature at i load =500ma figure 12. ground current vs temperature in dropout at i load =750ma figure 13. ground current vs temperature at i load =1.5a figure 14. ground current vs temperature in dropout at i load =1.5a 280 270 260 250 240 230 220 210 200 190 180 -40 -20 0 20 40 60 80 temperature ( c) ignd ( + a) 3.3v device v in = 4.3v il = 10ma cl = 10 + f 120 100 3.320 3.310 3.300 3.290 3.280 3.270 3.260 3.250 3.240 3.230 3.220 -40 -20 0 20 40 60 80 temperature ( c) v out (v) 3.3v device v in = 4.3v il = 10ma cl = 10 + f 120 100 7.00 6.80 6.60 6.40 6.20 6.00 5.80 5.60 5.40 5.20 5.00 -40 -20 0 20 40 60 80 temperature ( c) ignd (ma) 3.3v device v in = 4.3v il = 500ma cl = 10 + f 120 100 30 29 28 27 26 25 24 23 22 21 20 -40 -20 0 20 40 60 80 temperature ( c) ignd (ma) 3.3v device v in = 3.2v il = 750ma cl = 10 + f 120 100 52.0 50.0 48.0 46.0 44.0 42.0 40.0 38.0 36.0 -40 -20 0 20 40 60 80 temperature ( c) ignd (ma) 3.3v device v in = 4.3v il = 1.5a cl = 10 + f 120 100 100 95 90 85 80 75 70 -40 -20 0 20 40 60 80 temperature ( c) ignd (ma) 3.3v device v in = 3.2v il = 1.5a cl = 10 + f 120 100 typical performance characteristics
6 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation figure 15. dropout voltage vs temperature at i load =750ma figure 16. dropout voltage vs temperature at i load =1.5a figure 17. enable current vs temperature for 3.3v devices figure 18. enable threshold vs temperature for 3.3v devices 350 330 310 290 270 250 230 210 190 170 150 -40 -20 0 20 40 60 80 temperature ( c) v dropout (mv) 120 100 3.3v device il = 750ma cl = 10 + f 500 480 460 440 420 400 380 360 340 320 -40 -20 0 20 40 60 80 temperature ( c) v dropout (mv) 120 100 3.3v device il = 1.5a cl = 10 + f 35 30 25 20 15 10 5 0 -40 -20 0 20 40 60 80 temperature ( c) i en ( + a) 120 100 3.3v device v in = 3.2v il = 750ma cl = 10 + f 2.00 1.90 1.80 1.70 1.60 1.50 1.40 1.30 1.20 1.10 1.00 -40 -20 0 20 40 60 80 temperature ( c) v th (v) 120 100 3.3v device v in = 3.2v il = 750ma cl = 10 + f typical performance characteristics
date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation the spx294 incorporates protec - tion against over-current faults, re - versed load insertion, over temper - ature operation, and positive and negative transient voltage. thermal considerations although the spx294 offers limit - ing circuitry for overload conditions, it is still necessary to insure that the maximum junction temperature is not exceeded in the application. heat will fow through the lowest re - sistance path, the junction-to-case path. the tab of the device is elec - trically connected to gnd. in order to insure the best thermal fow of the component, proper mounting is required. consult heatsink manu - facturer for thermal resistance and design of heatsink. power dissipation is calculated as fol - lows: pd = (v in -v out )?( i out ) maximum junction temperature range: tj = t a ( max ) + pd? ja (thermal resis - tance, junction-to-ambient) maximum junction temperature must not exceed 2c. capacitor requirements the output capacitor is needed to insure stability and minimize the output noise. the value of the ca - pacitor varies with the load. how - ever, a minimum value of 10f aluminum capacitor will guarantee stability over all load conditions. a tantalum capacitor is recommended if a faster load transient response is needed. if the power source has a high ac impedance, a 0.1f ce - ramic capacitor between input & ground is recommended. minimum load current to ensure a proper behavior of the regulator under light load, a mini - mum load of ma for spx294 is required. typical application circuit figure 19 shows a typical applica - tions circuit for an adjustable output regulator. the values of r and r2 set the output voltage value as fol - lows: v out = v ref ? [ + (r/r2)]. a minimum value of 10k is rec - ommended for r2 with a range be - tween 10k to 47k. application information spx2941 v out v in gnd adj 4 2 3 5 1 r1 r2 10 f 6. 8 f + + en figure 19. adjustable output linear regulator
8 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation p ackage: 5 pin to-263
9 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation p ackage: 5 pin to-220
0 date: sept 28-06 rev e spx294 a low dropout linear regulator ? 2006 sipex corporation part number .................... accuracy ... output voltage ...................... package spx2941t5 ............................ 3% ........................ adj ............................. 5 lead to-263 spx2941t5/tr ...................... 3% ........................ adj ............................. 5 lead to-263 spx2941u5 ........................... 3% ........................ adj ............................. 5 lead to-220 package pinouts ordering information to-263-5 package (t5) top view 4 5 321 to-220-5 package (u5) top view 1 2 3 4 5 v in gnd v out 1) 3) 4) 5) 2) enable adjust spx2941 available in lead free packaging.to order add "-l" suffix to part number. example: spx2941t5/tr = standard; spx2941t5-l/tr = lead free /tr = tape and reel pack quantity is 500 for to-263-5. note: tab is internally connected to gnd sipex corporation headquarters and sales offce 2 south hillview drive milpitas, ca 9 0 tel: (408) 94-00 fax: (408) 935-7600 sipex corporation reserves the right to make changes to any products described herein. sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. solved by tm
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