preliminary datasheet LP3301 LP3301-datasheet dec.-2005 1 - 1 1.5mhz step-up dc/dc converter general description the LP3301 is a 1.5mhz pwm boost switching regulator designed for constant- voltage driver applications. the LP3301 implements a constant frequency 1.5mhz pwm control scheme. the high frequency pwm operation also saves board space by reducing external component sizes. to improve efficiency, the feedback voltage is set to 1.25v. highly integration and internal compensation network minimizes as 5 external component counts. optimized ope ration frequency can meet the requirement of small lc filters value and low operation current with high efficiency. ordering information LP3301 f:pb-free package type b5: sot-23-5 features high efficiency: 85% 1.5mhz fixed-frequency pwm operation 36v 500ma integrated switch shutdown supply current:<1ua available in sot23-5 package built-in over voltage protection of 29v minimize the external component rohs compliant and 100% lead (pb)-free pin configurations applications lcd bias supply oled driver gps/pda/mobile phone marking information please view website. typical application circuit 0.1uf 1uf 1uf 24v r2 10uh r1 vin 3 1 in5819 gnd 2 shdn 4 fb 3 vin 5 sw 1 LP3301 4.7uf LP3301 boost circuit for lcd bias LP3301 boost circuit vout=(r1/r2+1)x1.25 v 0.1uf 4.7uf vout=(r1/r2+1)x1.25 v 182k 10k on/off 10uf 1 3 2 bat54 +15v 100k 10uh 1.1m vin 1uf 47k 3 1 bat54/sot -15v 100pf gnd 2 shdn 4 fb 3 vin 5 sw 1 LP3301
preliminary datasheet LP3301 LP3301-datasheet dec.-2005 2 - 2 functional pin description sot-23-5 pin name pin function 1 sw switch pin. connect this pin to inductor and catch diode. minimize the track area to reduce emi. 2 gnd ground pin 3 fb feedback reference voltage pin. connect r1 and r2 resistor divider here. calculate the output voltage accordi ng to the formua:vout=1.25*(1+r1/r2). 4 shdn chip enable (active high). voltage sensing input to trigger the function of over voltage protection. note that this pin is high impedance. there should be a pull low 100k resistor connected to gnd when the control signal is floating. 5 vin supply input voltage pin. bypass 1uf capacitor to gnd to reduce the input noise. function block diagram
preliminary datasheet LP3301 LP3301-datasheet dec.-2005 3 - 3 absolute maximum ratings supply input voltage-------------------------------------------------------------------------------------------------- ? 0.3v to 16v lx input voltag e ------------------------------------------------------------------------------------------------------- ? 0.3v to 38v shdn input voltage --------------------------------------------------------------------------------------------- ? 0.3v to 16v ovp volt age------------------------------------------------------------------------------------------------------------ ? 0.3v to 29v the other pins --------------------------------------------------------------------------------------------------------- ? 0.3v to 5v power dissipation, p d @ t a = 25c sot-23-5 ---------------------------------------------------------------------------------------------------------------------- -0.455w lead temperature (sol dering, 10 sec. ) ----------------------------------------------------------------------------- 260c operation tempera ture range -------------------------------------------------------------------------------------- ? 40c to 80c junction temperature range ----------------------------------------------------------------------------------------0c to 125c storage temper ature range ---------------------------------------------------------------------------------------- ? 65c to 150c operation junction tempera ture range --------------------------------------------------------------------------0 c to 125c electrical characteristics parameter symbol test condition min typ max units system supply input operation voltage range v dd 2.6 16 v under voltage lock out v dd -- 2.2 v supply current i dd fb=0v, switch on 2 3.5 ma shut down current i dd v shdn= 0v ,v fb =0v 0.1 1 ua line regulation v in : 3.0~4.3v 3 % oscillator operation frequency f osc 1.1 1.5 1.9 mhz maximum duty cycle 85 90 % reference voltage feedback voltage (note 4) LP3301 1170 1250 1330 mv mosfet on resistance of mosfet r ds(on) -- 0.6 protection ovp threshold v ovp 29 v ovp sink current 5 a switching current limit 500 ma shut down voltage v en -- 0.4 v enable voltage v en 1.5 v soft star time 550 us
preliminary datasheet LP3301 LP3301-datasheet dec.-2005 4 - 4 typical performance characteristics
preliminary datasheet LP3301 LP3301-datasheet dec.-2005 5 - 5
preliminary datasheet LP3301 LP3301-datasheet dec.-2005 6 - 6 packing information
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