30 ics 1-1-3 dc/dc converter ics parameter reference voltage te mperature coefficient of reference voltage efficiency oscillation frequency line regulation load regulation overcurrent protection starting current quiescent circuit current ss pin outflow current at low voltage high level voltage en pin low level voltage inflow current at low low voltage error amplifier voltage gain error amplifier transformer conductance current sense amplifier impedance maximum on duty minimum on time features ?compact surface-mount package (hsop8) ?introduction of current mode control method ?output current: 3.5 a ?high efficiency: 90% (vo = 5 v) ?built-in reference oscillator (500 khz) ?a ceramic capacitor can be used for output ?built-in drooping-type overcurrent and thermal protection circuits ?built-in soft start circuit ?built-in on/off function (active hi) ?low current consumption during off applications ?dvd recorder, fpd-tv ?onboard local power supplies ?oa equipment unit v w c c c/w c/w symbol v in p d t j t stg j-c j-a parameter input voltage power dissipation *1 junction temperature *2 storage temperature thermal resistance(junction to case) thermal resistance(junction to ambient air) absolute maximum ratings conditions when mounted on glass-epoxy board, 30 30 mm (copper laminate area: 25 25 mm) when mounted on glass-epoxy board, 30 30 mm (copper laminate area: 25 25 mm) recommended operating conditions *1: the minimum value of the input voltage range is 4.75 v or vo +3 v, whichever is higher. parameter dc input voltage range output voltage range output current range operating junction temperature range operating temperature range symbol v in v o i o t jop t op unit v v a c c ratings si-8005q v o+3 *1 to 28 0.5 to 24 0 to 3.5 ?0 to +125 ?0 to +85 *1: limited by thermal protection circuit *2: note that the detection temperature for thermal protection is about 140 c. ratings 30 1.35 ?0 to +150 ?0 to +150 40 74 symbol v adj conditions ? v adj / ? t conditions conditions g p conditions ? v oline conditions ? v oload conditions i s conditions iq conditions iq (off) conditions i ssl conditions vc /en conditions vc /el conditions i c/eh conditions aea gea 1/gcs dmax dmin electrical characteristics unit v mv/ c % khz mv mv a ma a a v v a v/v a/v v/a % nsec. (r1=4.2k ? , r2=0.8k ? when ta = 25 c and vo=5v) *: pin 8 is the ss pin. soft start at power on can be performed with a capacitor connected to this pin. the ss pin is pulled up to the power supply in the ic, so applying the external voltage is prohibited. conditions rating 4 * 2 min. typ. max. 0.485 0.500 0.515 v in =12v, io=1a 0.05 v in =12v, io=1a, ta=?0 to +85 c 90 v in =12v, io=1a 450 500 550 v in =16v, io=1a 30 60 v in =8 to 28v, io=1a 30 60 v in =12v, io=0.1 to 3.5a 3.6 6.0 v in =12v 18 v in =12v, io=0a, v en =open 20 v in =12v, io=0a, v en =0v 5 v in =16v, v ssl =0v 2.8 v in =12v 2.2 v in =12v 5 v en =0v 1000 800 0.35 92 100 si-8008q ss 8 c8 soft start surface mount, current mode cntrol step-down switching mode SI-8000Q series
31 ics SI-8000Q series external dimensions (hsop8) (unit : mm) block diagram t ypical connection diagram 4.40 1.50 0.695 typ 5.20 a 1.27 0.40 0.4 0.05 0.05 0.15 0.08 0.08 pin 1 mark enlarged view of a 6.20 2.90 2.70 pin assignment 1 bs 2 in 3 sw 4 gnd 5 fb 6 comp 7 en 8 ss plastic mold package type flammability: ul 94v-0 product mass: approx. 0.1 g osc p.reg vref 0.5v 5v_ldo on off 7 en 6 comp 4 gnd 8 ss 1 bs 3 sw 5 fb 2 in uvlo ovp tsd amp 0.5v 5v_ldo drive pwm logic boot reg current sense ocp amp gnd c1 c5 8 7 6 c3 d1 r2 gnd c2 i adj r1 l1 v o c4 r3 c6 open 2 in en ss comp gnd 4 fb SI-8000Q sw bs 1 3 5 v in v fb c1:10 f/50v (murata:grm55db31h106ka87) c2:22 f/16v (murata:grm32er71a226ke20) c3:560pf *1 (murata:grm18 type) c4:10nf (murata: grm18 type) c5:10nf (murata: grm18 type) l1:10 h d1: spb-g56s (sanken) sjpb-l4 (sanken) r1:46k ? (vo=5v) r2:5.1k ? r3:24k ? *1 *1: when vo=5v
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