features applications general description high psrr makes it useful in applications that require ac noise suppression on the input power supply. low dropout voltage: 180mv@ 300ma (3.3v) accuracy within 2% quiescent current: 65 a typ. high psrr: 67db@100hz excellent line/load regulation fast response current limiting short circuit protection low temperature coefficient space saving packages sot2 v= shutdown current: 0.5 a thermal shutdown 3-5 and sc70-5 pb-free package cordless phone cellular phone bluetooth earphone digital camera portable electronics wlan m 3 player the PAM3103 is a positive, adjustable linear regulator. it features low quiescent current (65 a typ.) and low dropout voltage, making it ideal for battery powered applications. the output voltage is adjustable from 1.2v through 5v. its space-saving sot23-5 and sc70-5 packages are attractive for portable and handheld applications. it has both thermal shutdown and a current limit features to prevent device failure under extreme operating conditions. it is stable with an output capacitor of 2.2 f or greater. o p typical application PAM3103 300ma adjustable high psrr cmos linear regulator block diagram 1 www.poweranalog.com vin vout gnd en adj thermal protection error amp overcurrent shutdown reference v v *r1r2/r2 oref = (+) 09/2008 rev 1.2 r2 r1 c c 100pf c 2.2 f o c 1f in in out PAM3103 1 2 3 4 5 vin vout en gnd adj , power analog microelectronics inc
pin configuration & marking information 2 absolute maximum ratings these are stress ratings only and functional operation is not implied exposure to absolute maximum ratings for prolonged time periods may affect device reliability all voltages are with respect to ground . . . input voltage 6.6v output current 300ma output pin voltage gnd-0.3 lead soldering temperature(5sec) 300c storage temperature 65 to 150 ............................................... ......................................... ................ to v +0.3v ............ ....................- c c in recommended operating conditions max. supply voltage (for max. duration of 30 minutes)................................................6.4v ..................- c c .....................- c c junction temperature 40 to 125 ambient temperature 40 to 85 thermal information pin number name function 1 vin input 2 gnd ground 3 en chip enable (active high) 4 adj adjustable pin 5 vout output 123 54 acvyw top view sot23-5 ac: product code of pam3101 v: voltage code y: year w: week 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com 1 2 3 4 5 top view sc70-5 acvyw parameter symbol package maximum unit sot23-5 130 thermal resistance (junction to case) jc sc70-5 tbd c/w sot23-5 250 thermal resistance (junction to ambient) ja sc70-5 300 c/w sot23-5 400 internal power dissipation p d sc70-5 300 mw PAM3103 300ma adjustable high psrr cmos linear regulator
electrical characteristic t25 v ain == == 4v, v =3v, c 1 f, c 2.2 f, unless otherwise noted. oin o ? c, 3 09/2008 rev 1.2 parameter symbol test conditions min typ max units input voltage v in note 1 5.5 v output voltage v o 1.2 5 v reference voltage v ref 1.235 v output voltage accuracy v o i o =1ma -2 2 % output current i o 300 note 2 ma short circuit current i sc vo=0v 150 ma 2.5v vo < 3.3v 370 450 dropout voltage v drop i o =300ma vo 3.3v 180 230 mv ground current i gnd i o =1ma to 300ma 70 90 a quiescent current i q i o =0ma 65 90 a line regulation lnr i o =1ma, v in =3vto 5v -0.4 0.2 0.4 %/v load regulation ldr i o =1ma to 300ma -1 0.2 1 % temperature coefficient tc 40 ppm/ o c over temperature shutdown ots i o =1ma 150 o c over temperature hysteresis oth i o =1ma 30 o c f=100hz 67 db f=1khz 65 db power supply ripple rejection psrr io=100ma, vo=1.2v f=10khz 42 db output noise vn f =10hz to 100khz 50 vrms en input high threshold v ih v in =2.5v to 5v 1.5 v en input low threshold v il v in =2.5v to 5v 0.3 v shutdown current i sd v en =0v 0.01 1 a note1: the minimum input voltage ( ) of the PAM3103 is determined by output voltage and dropout voltage. : v=v+v note 2: output current is limited by p , maximum i =p /( -v ). v the minimum input voltage is defined as v in(min) in(max) in(min) o drop dodo , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
typical performance characteristics t 25 v =1.2v, c 1 f, c 2.2 f, unless otherwise noted. aoino === ? c, 4 1. output voltage vs input voltage 0.8 0.85 0.9 0.95 1 1.05 1.1 1.15 1.2 1.25 23456 input voltage(v) output voltage (v) i o =1ma i o =150ma i o =300ma 2. output voltage vs output current 1.175 1.18 1.185 1.19 1.195 1.2 1.205 0 50 100 150 200 250 300 output current(ma) output voltage(v) v in =4v v in =3v v in =5v 3. output voltage vs temperature 1.16 1.165 1.17 1.175 1.18 1.185 1.19 1.195 1.2 050100150 temperature( ) output voltage(v) i o =300ma i o =30ma 4. quiescent current vs input voltage 0 10 20 30 40 50 60 70 80 23456 quiescent current (a) input voltage(v) 5. ground current vs temperature 68 70 72 74 76 78 80 82 0 30 60 90 120 150 temperature( ) ground current (a) 6. ground current vs input voltage 0 20 40 60 80 100 120 23456 input voltage(v) ground current (a) i o =300ma i o =150ma i o =1ma 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
typical performance characteristics (continued) 5 7. load regulation transient response i =1ma to 100ma o i =1ma to 300ma o i =100ma to 300ma o 8. line regulation transient response 9. power supply ripple rejection vo ac coupling io dc coupling vo ac coupling io dc coupling vo ac coupling io dc coupling vo ac coupling v dc coupling in -80 +0 -70 -60 -50 -40 -30 -20 -10 d b 10 100k 20 50 100 200 500 1k 2k 5k 10k 20k 50k hz i =100ma o i=1ma o 09/2008 rev 1.2 io=1ma,v =3v to 5v in v =3v,vpp=1v in , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
6 capacitor selection and regulator stability adj output voltage programming load transient considerations shutdown input operation internal p-channel pass transistor input-output (dropout) voltage current limit and short circuit protection similar to any low dropout regulator, the external capacitors used with the PAM3103 must be carefully selected for regulator stability and performance. please note that the distance between c and the input pin of the PAM3103 should not exceed 0.5 inch. ceramic capacitors are suitable for the PAM3103. capacitors with larger values and lower esr (equivalent series resistance) provide better psrr and line-transient response. the PAM3103 is designed specifically to work with low esr ceramic output capacitors in order to save space and improve performance. using an output ceramic capacitor whose value is > the output voltage of the PAM3103 adjustable regulator is programed by using an external resistor divider as shown in figure1. the output voltage is calculated as below: v =v (1+r1/r2) resistor r1 and r2 should be chosen for approximately 7 a divider current. lower value resistors can be used but offer no advantage and waste more power. higher value should be avoided as leakage current at adj pin increase the output voltage error. v/v -1 curve7of on page 5 shows two components of the output response: a dc shift from the output impedance due to the load current change and transient response. the dc shift is quite small due to excellent load regulation of the PAM3103. the transient spike, resulting from a step change in the load current from 1ma to 300ma, is 20mv. the esr of the output capacitor is critical to the transient spike. a larger capacitance along with smaller esr results in a smaller spike. the PAM3103 can be shut down by pulling the en input low, and turned on by tying the en input to vin or leaving the en input floating. the PAM3103 features a 0.75 device as a pass transistor. the p- mos pass transistor enables the PAM3103 to consume only 65 a of ground current during low dropout, light-load, or heavy-load operation. this feature increases the battery operation life time. a regulator's minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. the PAM3103 has a typical 300mv dropout voltage. in battery- powered systems, this will determine the useful end-of-life battery voltage. the PAM3103 features a current limit, which monitors and controls the gate voltage of the pass transistor. the output current can be limited to 400ma by regulating the gate voltage. the PAM3103 also has a built-in short circuit current limit. in oref oref 2.2f with esr>5m ensures stability. p-channel mosfet a capacitor c of more than 1f can be employed in the input pin, while there is no upper limit for the capacitance of c . the PAM3103 load-transient response in in c is unnecessary when r1 or r2 <20k . the recommended design procedure is to choose r2=169k to set the divider current at 7 a and then calculate r1 as below: r1=( )r2 c ? application information 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
7 thermal considerations thermal protection limits power dissipation in the PAM3103. when the junction temperature exceeds 150c, the otp (over temperature protection) starts the thermal shutdown and turns the pass transistor off. the pass transistor resumes operation after the junction temperature drops below 120c. for continuous operation, the junction temperature should be maintained below 125c. the power dissipation is defined as below: p = (v -v )*i +v *i the maximum power dissipation depends on the thermal resistance of ic package, pcb layout, the rate of surrounding airflow and temperature difference between junction and ambient. the maximum power dissipation can be calculated by the following formula: where t is the maximum allowable junction temperature 125c, t is the ambient temperature and is the thermal resistance from the junction to the ambient. for example, as is 250c/w for the sot-23 package based on the standard jedec 51-3 for a single-layer thermal test board, the maximum power dissipation at t =25c can be calculated by following formula: p = (125c-25c)/250=0.4w it is also useful to calculate the junction temperature of the PAM3103 under a set of specific conditions. suppose the input voltage v =3.3v, the output current i =300ma and the case temperature t =40c measured by a thermal couple during operation, the power dissipation is defined as: p =(3.3v-2.8v)*300ma+3.3v*70ua 150mw and the junction temperature t can be calculated as follows: t=t t = 40c+0.15w*250c/w =40c+37.5c =77.5cPAM3103 in this configuration. d in out o in gnd j(max) a ja a d(max) in o a d j ja a j j(max) j p = (t -t )/ +p * d(max) j(max) a ja ja dj 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
ordering information PAM3103 xxxxxx output voltage number of pins package type pin configuration 8 09/2008 rev 1.2 pin configuration package type number of pins output voltage atype 1. vin 2. gnd 3. en 4. adj 5. vout a: sot-23 u: sc70 b: 5 adj part number output voltage marking package type standard package PAM3103aabadj adj acayw sot23-5 3,000units/tape&reel PAM3103aubadj adj acayw sc70-5 3,000units/tape&reel , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
outline dimension 9 d e1 e e1 a1 a2 a lref. 0.25 l1 (ref.) c(ref.) sot23-5 millimeter ref. min nom max a 1.10max a1 0 0.05 0.10 a2 0.70 1.00 1.295 c 0.12ref. d 2.70 2.90 3.10 e 2.60 2.80 3.00 e1 1.40 1.60 1.80 l 0.45ref. l1 0.60ref. 0o 5o 10o b 0.30 0.40 0.50 e 0.95ref. e1 1.90ref. 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
outline dimension 10 sc70-5 09/2008 rev 1.2 , power analog microelectronics inc www.poweranalog.com PAM3103 300ma adjustable high psrr cmos linear regulator
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