34 ics 1-1-3 dc/dc converter ics paramter reference voltage te mperature coefficient of reference voltage efficiency oscillation frequency line regulation load regulation overcurrent protection starting current low level voltage ss pin *1 outflow current at low voltage quiescent circuit current features ?surface-mount package (to263-5) ?output current: 5.5 a ?high efficiency: 83% (at typ, vo = 5 v) ?requires only 5 discrete components (si- 8008hd) ?built-in reference oscillator (150 khz) ?built-in drooping-type overcurrent and thermal protection circuits ?built-in soft start circuit (output on/off available) ?low current consumption during off applications ?dvd recorder, fpd-tv ?onboard local power supplies ?oa equipment absolute maximum ratings recommended operating conditions *1: the minimum value of the input voltage range is 4.5 v or vo+3 v, whichever is higher. parameter 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-8008hd v o+3 *1 to 40 0.8 to 24 0 to 5.5 ?0 to +100 ?0 to +85 symbol v adj conditions ( ? v adj / ? t) conditions conditions fo conditions ? v oline conditions ? v oload conditions i s conditions v ssl i ssl conditions i q conditions i q(off) conditions electrical characteristics unit v mv/ c % khz mv mv a v a ma a (r1=4.2k ? , r2=0.8k ? when ta=25 c and vo=5v) *1: pin 5 is the ss pin. soft start at power on can be performed with a capacitor connected to this pin. the output can also be turned on/off with this pin. the output is stopped by setting the voltage of this pin to vssl or lower. ss-pin voltage can be changed with an open-collector drive circuit of a transistor. when using both the soft-start and on/off functions together, the discharge current from c3 flows into the on/ off control transistor. therefore, limit the current securely to protect the transistor if c3 capacitance is large. the ss pin is pulled up (3.7 v typ.) to the power supply in the ic, so applying the external voltage is prohibited. if this pin is not used, leave it open. *1: limited by thermal protection circuit *2: this product has built-in thermal protection circuits that may activate when the junction temperature exceeds 130 c. the recommended design for the junction temperature during ic operation is below 125 c. unit v w c c c/w c/w ratings 43 3 +150 ?0 to +150 3 33.3 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) conditions when mounted on glass-epoxy board measuring 40 40 mm (copper laminate area: 100% ) when mounted on glass-epoxy board measuring 40 40 mm (copper laminate area: 100% ) when mounted on glass-epoxy board measuring 40 40 mm (copper laminate area: 100% ) conditions v in v o+3v ratings si-8008hd min. typ. max. 0.784 0.800 0.816 v in =15v, io=1a 0.1 v in =15v, io=1a, tc=0 to 100 c 83 v in =15v, io=3a 150 v in =15v, io=3a 60 80 v in =10 to 30v, io=3a 20 50 v in =15v, io=0.2 to 5.5a 5.6 6.5 7.5 v in =15v 0.5 10 30 v ssl =0v 6 v in =15v, io=0a 200 400 v in =15v, v ss =0v si-8008hd si-8008hd ss 5ss 5ss c3 c3 5 v o. on/off soft start soft start +vo. on/off si-8008hd surface-mount, separate excitation step-down switching mode SI-8000HD series
35 ics block diagram t ypical connection diagram reference data c 1 : 1500 f c 2 : 1000 f c 3 : 0.1 f (only when using soft-start function) c 4 : 4.7 f (gmr32er71h475ka88l (murata manufacturing) recommended) l 1 : 100 h d i : fmb-g16l (sanken) in c 1 c 4 c 3 di l 1 r 1 r 2 c 2 v in gnd ss gnd si-8008hd sw adj 12 4 3 5 + + v out gnd external dimensions (to263-5) (unit : mm) pin assignment 1 in 2 sw 3 gnd 4 adj 5 ss plastic mold package type flammability: ul 94v-0 product mass: approx. 1.48 g 15.30 0.3 (6.8) 9.2 0.2 4.9 0.2 (1.75) (2 r0.45) (1.7 0.25 ) (1.7 0.25 ) 0.8 0.1 10.0 0.2 (4.4) (8.0) (0.40) 2.54 0.3 (4.6) 9.2 0.2 1.2 0.2 4.9 0.2 (0.75) 2.0 0.1 15.3 0.3 9.9 0.2 case temperature measurement point (15 ) (0.5) 2-r0.3 10.0 0.02 3-r0.3 (r0.3) (r0.3) 0.88 0.10 1.5 dp: 0.2 (1.7 0.25 ) 12345 (1.7 0.25 ) 0.8 0.1 4.5 0.2 1.3 0.10 0.15 2.4 0.2 +0.10 ?.05 (3 ) (3 ) (3 ) (3 ) (3 ) 0 to 6 4 3 gnd 2 in ss sw adj 1 5 preg. ocp reset osc + comp. error amp. latch & drive tsd on/off soft start + + si-8008hd v ref the acceptable loss of the package is 3 w for the SI-8000HD series, so some ranges are not available, depending on the relation between the input voltage and output current. 55 50 45 40 35 30 0 200 400 600 800 1000 copper laminate area (mm 2 ) 1200 1400 1600 1800 when using glass-epoxy board measuring 40 40 mm thermal resistance (junction to ambient air temperature) j-a ( c/w) SI-8000HD series
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