YB mA, Low Power, High PSRR LDO Regulator

Transcription

1 scription Th is a sris of ultra-low-nois, high PSRR, and low quiscnt currnt low dropout (O) linar rgulators with 2.0% output voltag accuracy. Th rgulators achiv a low 300m dropout at 300m load currnt of 3.6V output and ar availabl in voltags ranging from 1.2V to 3.6V with 0.1 V pr stp (custom voltag is considrat at rqust). Th rgulators ar optimizd to work with low-sr and low cost cramic capacitors, rducing th amount of board spac critical in portabl dvics. Th rquirs only 1.0μF output capacitor for stability with any load and consums lss than 1μ in shutdown mod. Built-in thrmal shutdown and short-circuit currnt limit offr scur protction against fault opration. rgulators also includ an auto-discharg function. Th rgulators ar availabl in SOT-23 / SOT-25 / SOT-89 packags. Faturs High ccuracy Output Voltag : + 2% Wid Output Voltag Rang : 1.2~3.6V Ultra-ow-Nois ow-rop-out Typical Output urrnt : 300 m ow Quiscnt urrnt: ~10μ 300mV ropout at 300m 3.6V Output Stabl with 1.0μF ramic apacitor Only Nd Input and Output apacitors Thrmal Protction Shutdown uto discharg function Grn Packag (RoHS) vailabl pplications P, Notbook, P omputrs S, llular phons PMI ards, P amras USB Basd Portabl vics GSM/GPRS/3G RF Transcivr Wirlss Ns Blutooth Portabl Radios Battry-Powrd vics Typical pplication ircuitry Input in=1uf ON OFF VIN VOUT N GN Output out=1uf Input in=1uf VIN VOUT GN Output out=1uf Figur 1-1 : SOT-25 application circuit Figur 1-2 : SOT-23 application circuit Rv

2 Pin onfiguration VIN 3 VOUT 5 N 4 SOT-89 SOT-89R SOT-23 SOT GN VIN VOUT VOUT GN VIN 1 2 GN VOUT 1 2 VIN GN 3 N Figur 2 : pin configuration Pin scription Tabl 1 Pin Nam VIN GN N N VOUT Pin Function Unrgulatd Input Supply. Bypass with a capacitor to GN Ground pin Pull high to nabl th rgulator No connction is rquird Rgulatd Output Voltag Rv

3 Ordring Information X Output Voltag 120 : 1.2V 130 : 1.3V : 360 : 3.6V X : fixd Packag Typ ST23 : SOT-23 ST25 : SOT-25 ST89 : SOT-89 ST8R : SOT-89R *Ordr xampl : ST89X250 for of 2.5V output and SOT-89 packag *Shipping Quantity : SOT-23 : 3000 units tap & rl SOT-25 : 3000 units tap & rl SOT-89 : 1000 units tap & rl SOT-89R : 1000 units tap & rl *Only grn packag Marking Information bsolut Maximum Ratings (Not 1) Supply Voltag V to 6.0V Output Voltag V to (V IN +0.3V) Output Short-ircuit uration... Infinit Junction Tmpratur Rang Storag Tmpratur Rang to +150 ad Tmpratur S Suscptibility (HBM) 2KV S Suscptibility (MM) V Rcommndd Oprating onditions (Not 2) Input Supply Voltag...2V to 5.5V Oprating Tmpratur to +85 Thrmal Information (Not 3) Thrmal Rsistanc (SOT-23/25, θj).280 /W Thrmal Rsistanc (SOT-89, θj) /W Intrnal Powr issipation (SOT-23/25, P) 0.4W Intrnal Powr issipation (SOT-89, P)0.55W Not: 1. xcding ths ratings may damag th dvic. 2. Th dvic is not guarantd to function outsid of its oprating conditions. 3. θ J is masurd in fr air at T = 25 on a low ffctiv thrmal conductivity board. Rv

4 lctrical haractristics Tabl 2 T = 25, V IN = ( V OUT + 1 V ), IN = OU T = 1.0μF, V N = V IN, unlss othrwis t d Function Paramtr onditions Min Typ Max Units Input Voltag Rang V Output Voltag, VOUT Prdfind V Output Voltag ccuracy I OUT = 10m, VOUT >= 1.3V % I OUT = 10m, VOUT = 1.2V % Output urrnt imit Short-circuit output 500 m Vout = 3.6V, Iout = 300 m 300 Vout = 3.3V, Iout = 300 m 350 ropout Voltag (Not 1) Vout = 2.8V, Iout = 300 m 430 mv Vout = 1.8V, Iout = 300 m 600 Vout = 1.2V, Iout = 300 m 900 Ground urrnt Iground = Iin - Iout 10 μ in Rgulation Vin = (Vout+1V) to 5.5V, Iout =10m %/V oad Rgulation Iout = 1m to 300 m %/m Shutdown Supply urrnt N = Vin=0V 1 μ Rippl Rjction (PSRR) (Not 2) 50 db Start Up lay (Not 3) Rload=100ohm 200 μs Shutdown lay Rload=10K ohm, VOUT=1.5V 1 ms Rload=10K ohm, VOUT=1.2V 1 ms N ogic ow vl Vin = 2.0V to 5.5V 0.4 V N ogic High vl Vin = 2.0V to 5.5V 1.2 Vin V N Input Bias urrnt Vin = N = 3V 1.5 μ Thrmal Shutdown Shutdown Tmpratur 160 Thrmal Hystrsis 20 Not 1: Th dropout voltag varis dpnding on output voltag slction. ropout is dfind as VIN VOUT whn VOUT is 100mV blow nominal VOUT whr Vin=Vout + 1V for nominal VOUT. Not 2: PSRR is tstd at Vin=3.8+1Vppac, Vout=2.8V, I_load=1m. Not 3: Tim ndd for VOUT to rach 90% of final valu. Rv

5 Typical haractristics t T =25, V IN =(V OUT +1V), IN = OUT =1.0μF, V N =V IN, unlss othrwis notd. Output urnt VS ropout voltag Input voltag VS Quiscnt currnt ropout Voltag (mv) Iout= 300m V V V Output currnt (m) Quiscnt currnt (u) Iout= V V input voltag (V) Output voltag VS Tmpratur Output voltag VS Output currnt Output Voltag (V) Iout= 300m 3.3V 1.8V Ouput voltag (V) V 1.8V Tmpratur (dgr) Output currnt (m) Startup dlay tim Shutdown dlay tim Rout = 10Ω Vout = 3.3V N Rout = 10Ω Vout = 3.3V N Vout Vout Rv

6 Input transint rspons oad transint rspons Vout VIN 4V Iout=100m Vout =3.3V 6V Iout Vout 10m 250m VIN=4.3V Vout =3.3V Powr supply rjction ratio Powr supply rjction ratio Vin=3.8V + 1V P-P, out=1.0μf Vout=2.8V Iout=1m Vin=3.8V + 1V P-P, out=1.0μf Vout=2.8V Iout=10m Rv

7 Functional Block iagram VIN N Vrf VOUT Thrmal shutdown Short ircuit Protction Functional scription GN Figur 3 : Function diagram Th is an ultra-low-nois, low-quiscnt currnt, low-dropout linar rgulator. It is supplid in a SOT-23 / SOT-25 / SOT-89 packag for diffrnt applications. can supply load currnt up to 300m (typical opration, not maximum) with good lin and load rgulation. Output voltags ar prst and ranging from 1.2V to 3.6V. s shown in th Functional Block iagram, th consists of a rfrnc and nois bypass circuit, rror amplifir, output driv transistor, intrnal fdback voltag dividr, thrmal snsor, and short circuit currnt limitr. Th intrnal rfrnc is connctd to th rror amplifir s invrting input. Th rror amplifir compars this rfrnc with th fdback voltag and amplifis th diffrnc. If th fdback voltag is lowr than th rfrnc voltag, th gat of th pass-transistor is pulld low. This allows mor currnt to pass to th output and incrass th output voltag. If th fdback voltag is too high, th gat of th pass transistor is pulld high, allowing lss currnt to pass to th output. Stability Th is a high prformanc O mphasizing stability with low output capacitanc. It is abl to maintain stability with an output capacitor as low as 1.0µF. Th output capacitor can also b incrasd to optimiz prformanc. Th will rmain stabl and in rgulation with no load, unlik many othr voltag rgulators. Rv

8 Intrnal P-hannl Pass Transistor Th faturs a low impdanc P-channl MOSFT pass transistor. This provids svral advantags ovr similar dsigns using a PNP pass transistor, including low oprating powr and longr battry lif. Th consums only 10µ of quiscnt currnt undr most conditions. Output Short-ircuit urrnt imit Th includs a currnt limitr, which monitors and controls th pass transistor s gat voltag, limiting th output currnt to about 500m, for xampl, in a short-circuit output situation. Shutdown Th also faturs a low-powr activ shutdown mod. It has a switch that turns off th dvic whn disabld. This allows th output capacitor and load to discharg and d-nrgiz th load. In th shutdown mod, th intrnal functional blocks, such as voltag rfrnc and th rror amplifir ar turnd off compltly, and th quiscnt currnt is lss than 1µ. pplication Information nabl/shutdown Th coms with an activ-high nabl pin that allows th rgulator to b nabld. Forcing th nabl pin low disabls th rgulator and puts it into th shutdown mod. This pin cannot b lft floating as it may caus an undtrmind stat. Input/Output apacitor It is rcommndd to us a 1.0µF capacitor in th input and a 1.0µF capacitor in th output. For high rgulation prformanc, largr input capacitor valus and lowr SRs provid bttr nois rjction and lin-transint rspons. Th output nois, load-transint rspons, stability, and powr-supply rjction can b improvd by using larg output capacitors. ow SR cramic capacitors provid optimal prformanc and sav spac. Thrmal Protction Shutdown Th thrmal protction shutdown function protcts th dvic from oprating in ovr tmpratur condition. Whn th junction tmpratur xcds +160, th thrmal snsor signals th shutdown logic, turning off th pass transistor and allowing th I to cool down. Th thrmal snsor turns th pass transistor on again aftr th I s junction tmpratur drops to Rv

9 SOT-25 Packag Information bx5 2 1 GUG PN t Symbol milimtrs Inchs MIN. MX. MIN. MX. 1 2 b t BS BS BS BS BS BS RF RF Rv

10 SOT-23 Packag Information b? GUG PN t Symbol milimtrs Inchs MIN. MX. MIN. MX. 1 2 b t BS BS BS BS BS BS RF RF Rv

11 SOT-89 Packag Information 1 bx2 b1 1 b2 Symbol milimtrs Inchs MIN. MX. MIN. MX. b b1 b BS..059 BS BS..118 BS Rv