technical data 2011, february, rev. 0 1 c onstant v oltage and c onstant c urrent c ontroller for a daptors and b atte ry c hargers description ik3052a is a highly integrated solution for smps applications requiring constant voltage and constant current mode. ik3052a integrates one voltage ref erence, two operational amplifiers (with ored outputs ? common collectors), and a current sensing circuit. the voltage reference combined with one operational amplifier makes it an ideal voltage controller, and the other low voltage reference combined with the other operational amplifier makes it an ideal current limiter for output low side current sensing. the current threshold is fixed and precise. the only external components are: ? a resistor bridge to be connected to the output of the power supply (adapt er, battery charger) to set the voltage regulation by dividing the desired output voltage to match the internal voltage reference value. ? a sense resistor having a value and allowable dissipation power which need to be chosen according to the internal volta ge threshold. ? optional compensation components (r and c). ik3052a , is ideal for smallest package available, is ideal for space shrinked applications such as adapters and battery chargers. features ? constant voltage and constant current control ? low v oltage operation ? precision internal component count ? current sink output stage ? easy compensation ? low ac mains voltage rejection pin connection (top view) pin definitions and functions sot23 - 6 pin out n ame pin# type function vcc 6 power supply positive power supply line gnd 2 power supply ground line. 0v reference for all voltages vctrl 1 analog input input pin of the voltage control loop ictrl 4 analog input input pin of the current control loop o ut 3 current sink output output pin. sinking current only vsense 5 analog input input pin of the current control loop ik3052a orderi ng i nform ati on device operating temperature range package shipping ik3052a s2t t a = 0 to 85 c f or all packages plastic sot23 - 6 tape& reel
ik3052a 2011, february, rev. 0 1 absolute maximum ratings symbol parameter value unit vcc dc supply voltage 20 v vi input voltage - 0.3 to vcc v top operating fr ee air temperature range 0 to 85 o c tj maximum junction temperature 150 o c * stresses beyond 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 condi tions beyond those indicated under ?recommended operating conditions? is not implied. exposure to absolute - maximum - rated conditions for extended periods may affect device reliability. operation conditions symbol parameter value unit vcc dc supply conditions 2.5 to 1 8 v electrical characteristics tamb = 25 c and vcc = +5v (unless otherwise specified) s ymbol parameter test condition min typ max unit total current consumption icc total supply current ? not taking the output sinking current into account tamb 0 < tamb < 85c 1.1 1.2 2 ma voltage control loop gmv transconduction gain (vctrl). sink cu rrent only 1) tamb 0 < tamb < 85c 1 3.5 2.5 ma/mv vref voltage control loop reference 2) tamb 0 < tamb < 85c 1. 204 1.186 1.21 1.2 16 1.234 v iibv input bias current (vctrl) tamb 0 < tamb < 85c 50 100 na current control loop gmi transconduction gai n (ictrl). sink current only 3) tamb 0 < tamb < 85c 1.5 7 ma/mv vsense current control loop reference 4) iout = 2.5 ma tamb 0 < tamb < 85c 196 192 200 204 208 mv iibi current out of pin ictrl at - 200mv tamb 0 < tamb < 85c 25 50 a output stage vol low output voltage at 10 ma sinking current tamb 0 < tamb < 85c 200 mv ios output short circuit current. output to vcc. sink current only tamb 0 < tamb < 85c 27 35 50 ma 1. if the voltage on vctrl (the negative input of the am plifier) is higher than the positive amplifier input (vref=1.210v), and it is increased by 1mv, the sinking current at the output out will be increased by 3.5ma. 2. the internal voltage reference is set at 1.210v (bandgap reference). the voltage control l oop precision takes into account the cumulative effects of the internal voltage reference deviation as well as the input offset voltage of the trans - conductance operational amplifier. the internal voltage reference is fixed by bandgap, and trimmed to 0.5% accuracy at room temperature. 3. when the positive input at ictrl is lower than - 200mv, and the voltage is decreased by 1mv, the sinking current at the output out will be increased by 7ma. 4. the internal current sense threshold is set to - 200mv. the cur rent control loop precision takes into account the cumulative effects of the internal voltage reference deviation as well as the input offset voltage of the trans - conduction operational amplifier.
ik3052a 2011, february, rev. 0 1 t ypical application circuit typical adaptor or battery charger application using the device in the above application schematic, the device is used on the secondary side of a flyback adaptor (or battery charger) to provide an accurate control of voltage and current. the above feedback loop is made with an optocoupler. attention! for measurements of electrical characteristics of ik3052a and also in field application of the devices in composition of equipment, it is necessary to apply capacitance cout 0.47 pf on pin 3 (out).
ik3052a 2011, february, rev. 0 1 package dimension sot - 23- 6 symbol dimensions in millimeters dimensions in inches min max min max a 1.050 1.250 0.041 0.049 a1 0.000 0.100 0.000 0.004 a2 1.050 1.150 0.041 0.045 b 0.300 0.500 0.012 0.020 c 0.100 0.200 0.004 0.008 d 2.820 3.020 0.111 0.119 e 1.500 1.700 0.059 0.067 e1 2.650 2.950 0.104 0.116 e 0.950typ 0.037typ e1 1.800 2.000 0.071 0.079 l 0.600ref 0.024ref l1 0.300 0.600 0.012 0.02 4 0 8 0 8
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