MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 1 dc to dc converter controller ? description ? features ? applications the MC34063 is a monolithic switching regulator control circuit containing the primary functions required for dc-dc converters. this devices consists of internal temperature compensated reference, voltage comparator, controlled duty cycle oscillator with active current limit circuit, driver and high current output switch. the device is specifically designed to be incorporated in step-down,step-up and voltage-inverting applications with a minimum number of external components. ? operation from 3.0v to 40v ? low standby current. ? current limiting ? output switch current to 1.2a ? output voltage adjustable ? operation frequency up to 180khz (c t =100pf) ? precision 2% reference ? battery chargers ? adsl modems ? nics/switches/hubs ? negative voltage power supplies ? block diagram ? pin description et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 2 ? ordering information part number operating temperature range package packing MC34063ki sop-8 tape & reel MC34063ji -40 o c ~ +85 o c dip-8 tube ? absolute maximum ratings (note1) symbol parameter value unit v cc power supply voltage 40 v v ir comparator input voltage range -0.3 ~ +40 v v c(switch) switch collector voltage 40 v v e(switch) switch emitter voltage (v pin1 =40v) 40 v v ce(switch) switch collector to emitter voltage 40 v v c(driver) driver collector voltage 40 v i c(driver) driver collector current (note2) 100 ma i sw switch current 1.2 a t j operating junction temperature range +150 o c t a operating ambient temperature range -40 ~ +85 o c t stg storage temperature range -65 ~ +150 o c esd 2000 v notes: 1 stresses greater than those listed under .absolute maximum ratings. may cause permanent damage to the device. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under .recommended operating conditions. is not implied. exposure to .absolute maximum rating s. for extended periods may affect device reliability. 2 maximum package power dissipation limits must be observed. ? thermal characteristics symbol parameter package typical value unit sop-8 160 ja thermal resistance from junction to ambient in free air. (measured with the component mounted on a high effective thermal conductivity test board in free air.) dip-8 100 o c/w et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 3 ? electrical characteristics (t a =25 c, v cc =5.0v, unless otherwise noted . ) symbol parameter test condition min. typ. max. unit oscillator f osc frequency v pin5 =0v, c t =1.0nf 30 38 45 khz i chg charge current v cc =5.0v to 40v 30 38 45 ua i dischg discharge current v cc =5.0v to 40v 180 240 290 ua i dischg /i chg discharge to charge current ratio pin 7 to v cc 5.2 6.5 7.5 - v ipk(sence) current limit sense voltage i cha =i discha 250 300 350 mv output switch (note3) v ce(sat) saturation voltage, darlington connection i sw =1.0a, pins 1,8 connected - 1.0 1.3 v v ce(sat) saturation voltage, (note4) i sw =1.0a, r pin8 =82 to v cc , forced =20 - 0.45 0.8 v h fe dc current gain i sw =1.0a, v ce =5.0v 50 75 - - i c(off) collector off-state current v ce =40v - 0.01 100 ua comparator t a =25 c 1.225 1.275 v th threshold voltage t a =-40 c to +85 c 1.21 1.25 1.29 v reg line threshold voltage line regulator v cc =3.0v to 40v - 1.4 5.0 mv i ib input bias current v in =0v - -20 -400 na total device i cc supply current v cc =5.0v to 40v, c t =1.0nf, pin 7=v cc v pin 5 >v th , pin2=gnd remaining pins open - - 4.0 ma notes: 3. low duty cycle pulse techniques are used during te st to maintain junction temperature as close ambient temperature as possible. 4.if the output switch is driven into hard saturation (non-darlington configuration) at low switch currents ( 300ma) and high driver currents ( 30ma), it may take up to 2.0 s for it to come out of saturation. this condition will shorten the off time at frequencies 30 khz, and is magnified at high temperatures. this condition does not occur with a darlington configuration, since the output switch cannot saturate. if a non-darlington configuration is used, the following output drive condition is recommended: forced of output switch: 10 * the 100 resistor in the emitter of the driver device requires about 7 ma before the output switch conducts. i c(output) i c(driver)- 7.0ma* et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 4 ? typical characteristics et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 5 ? typical application circuits et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 6 ? typical application circuits (continued) et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 7 ? typical application circuits (continued) et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 8 ? design formula table v sat : saturation voltage of the output switch. v f : forward voltage drop of the output rectifier. the following power supply characteristics must be chosen. v in : nominal input voltage. v out : desired output voltage. i out : desired output current. f min : minimum desired output switch frequency at the selected values of v in an i o . v ripple(pp) : desired peak-to-peak output ripple voltage. in practice, the calculated capacitor value will need to be increased due to its equivalent series resistance and board layout. the ripple voltage should be kept to a low value since it will directly affect the line and load regulation. et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 9 ? package information sop-8 et-
MC34063 www.estek.com.cn copyright @ estek electronics co., ltd version 0.3 27 sep 2011 10 ? package information dip-8 et-
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