bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com 150 ma cmos low dropout ldo b4150 on/off & bypass pin connection ordering information -40 c to +125 c package part no. sot-25 b4150ck5 -x.x x.x = fixed output voltages from 2.0v to 6.0v description the b4150 series are a group of positive output voltage, five-pin regulators, which provide a high current even when the input/output voltage differential is small. low power consumption and high accuracy is achieved though cmos and programmable fuse technologies. output voltage: 2.0v to 6.0v in 0.1v increments. the b4150 consists of a high-precision voltage reference, an error correction circuit, and a current limited output driver. key features include a shutdown pin that reduces supply current to 0.5 a max and a 470pf bypass input to ground reduces noise present on the internal reference, which in turn significantly reduce output noise. if output noise is not concern, this input maybe left unconnected. larger capacitor values cap be used, but results in longer time period to rated output voltage when power initially applied. the on/off pin enables the output to be turned off, resulting in reduced power consumption. provided in sot-25 (150mw) packages minimizes the usage of b oard real state. features ? maximum output cu rrent:????... 150 ma. ? highly accurate: output voltage?... +/- 1.4%. ? shutdown supply current??????0.1 a ? ground current of less than?????. 2 a ? cmos low power consumption. 0.165v at 150ma 0.110v at 100ma ? low output noise: 30vrms ? high ripple rejection: 70db(10khz) ? shut down mode for power savings ? reference bypass for ultra low noise ? improve pin-to-pin tc1185/xc6204/s-814 ? pin-to-pin low power to bipolar ldo?s mic5205 / lp2985/lt1761 applications ? battery powered equipment ? notebook pc, palmtops, pda ? portable cameras and video recorders ? reference voltage sources ? cellular / gsm / pcs phones sot-25 (k5) top view on/off v in gnd 3 2 1 4 5 v out bypass bay linear inspire the linear power battrey 1 f v in gnd shdn v out bypass shutdown control (to cmos logic or tie to v in if unused) 470pf reference bypass cap (optional) 1 f b4150 battrey 1 f v in gnd shdn v out bypass shutdown control (to cmos logic or tie to v in if unused) 470pf reference bypass cap (optional) 1 f b4150
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 absolute maximum ratings parameter symbol ratings units input voltage v in 6.5 v output current i out 150 ma ce output voltage v out v ss -0.3 to v in 0.3 v continual total power dissipation sot-25 sot-89 pd 150 300 mw operating ambient temperature t opr -30 to 80 c storage temperature t stg -40 to 125 c electrical characteristics (t a = 25 c, v in = v out + 0.5v; unless otherwise noted) parameter conditions min typ max unit i o = 1ma -1.4% - +1.4% output voltage accuracy i o = 0 to 150ma -2% - +2% v line regulation ? v out / ? v in -v out i o = 100ma, (v out + 0.1v) bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 product description the b4150 is precision fixed output voltage regulator. unlike bipolar regulators, the b4150 supply current does not increase with load current. in addition, v out remains stable and within regulator at very low load currents (an important consideration in rtc and cmos ram battery back-up application). figure 1 shows a typical application circuit. the regulator is enabled any time the shutdown input is at or above v ih. and shutdown (disabled) when shdn is at or below v il . shdn maybe controlled by a cmos logic gate, or i/o port of a micro controller. if the shdn input is not. required, it should be connected directly to the supply. while in shutdown, supply current decreases to 0.05 a (typical) and v out falls to zero volts. bypass input a 470pf capacitor connected from the bypass input to ground reduces noise present on the internal reference, which in turn significantly reduces output noise. if output noise is not a concern, this input maybe left unconnected. larger capacitor values maybe used, but it results in a longer time period to rated output voltage power is initially applied. output capacitor a 1 f (min) capacitor from v out to ground is required. then output capacitor should have an effective series resistance of 5 ? or less. a 1 a capacitor should be connected from v in to gnd if there is more than 10 inches of wire between the regulator and the ac filter capacitor, or if a battery is used as the power source. aluminum electrolytic or tantalum capacitor types can be used. (since many alumi num electrolytic capacitors freeze at approximately- 30 c, solid tantalums are recommended for applications operating below ?25 c.) when operating from sources other than batteries, supply-noise rejection and transient response can be improved by increas ing the value of the input and output capacitors and employing passive filtering techniques. thermal considerations thermal shutdown integrated thermal protection circuitry shuts the regulator off when die temperature exceeds 160 c. the regulator remaining off until the die temperature drops to approximately 150 c. power dissipation the amount of power the regulator dissipates is primarily a function of input and output voltage, and output current. the following equation is used to calculate worst case power dissipation: p d =(v inmax -v outmin )i loadmax where: p d = worst case actual power dissipation v inmax = maximum voltage on v in v outmin =minimum regulator output voltage i loadmax = maximum output (load) current the maximum allowable power dissipation is function of the maximum ambient temperature (t amax ). the maximum allowable die temperature (125 c) and the thermal resistance from junction-to-air ( ja ). the 5- pin sot-23a package has a ja of approximately 220 c/watt when mounted on a single layer fr4 dielectric copper clad pc board. p dmax =(t jmax -t amax )/ ja where all terms are previously defined this can be caused in conjunction with other equation to ensure regulator thermal operation is within limit. for example: given: v inmax =3.0v+10% v outmin =2.7v-2.5% i loadmax =40 ma t jmax =125 c t amax =55 c find: 1. actual power dissipation 2. maximum allowable dissipation actual power dissipation: p d =(v inmax -v outmin )i loadmax =[(3.0 x 1.1)-(2.7 x 0.975)]40 x 10 -3 =26.7mw maximum allowable power dissipation: p dmax =(t jmax -t amax ) =(125-55)/220 =318mw these equations can be used to calculate maximum current and/or input voltage limits.
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 test circuits
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 output voltage vs. output current output voltage vs. input voltage b4150-2.5 b4150-3.0 b4150-2.5
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 dropout voltage vs. output current input transient response b4150-3.0 b4150-2.5 b4150-3.0
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 load transients response turn on response time ripple rejection output noise b4150-3.0 b4150-3.0 b4150-3.0 b4150-3.0
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com b4150 sot-25 packaging outline l a1 c a2 a d b (5 places) h e e1 e millimeters symbol 0 0.90 0.30 0.80 ref 2.70 0.10 1.40 1.70 0.95 bsc. min 0.2 2.50 min. max min. max. a a1 a2 b c d e e e1 h l 0 .035 .012 .0315 ref .106 .004 .055 .066 .037 bsc. min .0078 .098 0.10 1.30 0.50 3.10 0.35 1.80 2.10 3.00 .004 .051 .019 .122 .0137 .071 .082 .118 inches note: 1. refer to applicable 2. controlling dimention : millimeter 3. package surface finishing to be smoot h finish.
bay linear, inc 2418 armstrong street, livermore, ca 94550 tel: (925) 606-5950, fa x: (925) 940-9556 www.baylinear.com advance information - these data sheets contain descriptions of products that are in development. the specifications are based on the engineering ca lculations, computer simulations and/ or initial prototype evaluation. preliminary information - these data sheets contain minimum and maxi mum specifications that are based on the initial device characterizations. these lim its are subject to change upon the completion of the full characterization over the specif ied temperature and supply voltage ranges. the application circuit examples are only to explain the repres entative applications of the de vices and are not intended to gua rantee any circuit design or permit any industrial property ri ght to other rights to execute. bay linear takes no responsibility for any problems related to any industrial property right resulting from the use of the contents shown in the da ta book. typical parameters can and do vary in different applications. customer?s technical experts must validate all operating parameters including ? typical? for each customer applic ation. life support and nuclear policy bay linear products are not authorized fo r and should not be used within life suppor t systems which are intended for surgical implants into the body to support or sustain life, in aircraft, space equipment, submarine, or nuclear facility applications wi thout the specific written consent of bay linear president.
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