rp400x series current mode pwm/vfm step-up dc/dc converter no.ek-193-091101 step-up dc/dc converter the rp400x series are cmos-based automatic switch pwm- or vfm-controlled step-up dc/dc converters. rp400x includes a soft start circuit. by simply using an inductor, a capacitor, a diode, and (resistors) as external components, a high-efficiency ste p-up dc/dc converter can be easily configured. due to current mode pwm control, the rp400x provides a fast response and high efficiency. ceramic output capacitors can be used. the output voltage can be selected from the internally fixed or the external ly adjustment. the rp400x has an anti-ringing switch that prevents inductor current from ringing in pwm discontinuous mode. rp400x switches automatically to vfm control in low output current, keeping high efficiency. in addition to sot-23-5 package, a 1.8mm 2.0mm square dfn(plp)1820-6 package is also available. features ? supply current (i dd1 )typ. 300 a (rp400x301, v in =v out =set v out 0.95) ? supply current (i dd2 )typ. 160 a (v in =5v, in non-switching) ? standby current (i standby ) max. 3 a (in standby, only a version) ? input voltage range (v in ) 0.9v to 5.5v ? start-up voltage (v start ) max. 0.9v ? output voltage range (v out )1.8v to 5.0 v (internally fixed) (xx1) externally adjustable (feedback voltage of 0.6v) (001) ? output voltage accuracy 2% ? oscillator frequency (f osc ) 700khz ? oscillator maximum duty cycle (maxduty) typ. 88% ? soft start time (t start ) typ. 0.7ms ? anti-ringing switch internal emi suppression ? packages dfn(plp)1820-6, sot-23-5 block diagrams rp400xxx1x rp400k001x (internally fixed output voltage type) (externally adjustable output voltage type) v in ce l x v out gnd chip enable control lo g ic pwm control buffer current sense vref startup circuit erroramp fosc vfm control osc v in ce l x v fb gnd chip enable control lo g ic pwm control buffer current sense vref startup circuit erroramp fosc v out vfm control osc selection guides typical applications package quantity per reel part no. dfn(plp)1820-6 5,000 pcs rp400k . xx . 1 . ? -tr sot-23-5 3,000 pcs rp400n . xx . 1 . ? -tr-f . xx . : specify the output voltage within the range 1.8v ( . 18 . ) to 5.0v ( . 50 . ) in 0.1v steps. for the externally adjustable output voltage type, ( . 00 . ). . ? : select from ( . a . ) with ce pin or ( . b . ) without ce pin. rp400xxx1a (internally fixed output voltage type) v in ce gnd v out l x "h"active c in 10 f c out 10 f out v in l10 h rp400x sd rp400x001a (externally adjustable output voltage type) v in ce gnd v out l x "h"active c in 10 f v out 1.8v to 5.0v v in l10 f v fb r2 r1 packages typica l characteristic dfn(plp)1820-6 sot-23-5 top view bottom view 6 5 4 1 2 3 4 5 6 3 2 1 ? 1 3 5 4 2 xx1a 001a xx1b 001b 1 v in v in v in v in 2 ce ce nc nc 3 gnd gnd gnd gnd 4 l x l x l x l x 5 nc v fb nc v fb 6 v out v out v out v out xx1a xx1b 1 ce nc 2 gnd gnd 3 v in v in 4 v out v out 5 l x l x rp400x001a efficiency vs. output current ? ) the tab is substrate level (gnd). applications ? mp3 players and pda ? digital cameras ? lcd bias power supply ? personal medical equipment ? wireless handset ? gps only a version only a version 40 100 90 50 70 60 80 0 400 200 600 800 output current i out (ma) efficiency (%) set v out =3.0v v in =2.5v v in =1.8v v in =1.5v v in =0.8v
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