1 IK3301 rev. 01 description IK3301 is to be used as power supply control ic for the system that is based on ccd image sensor. ik33 01 supplies all the voltages that are needed to operat e ccd image sensor, 15v, 5v and ?8v, with excellent ly controlled ripple voltage. the typical power effici ency of this device is 80% at a standard load curre nt. due to the high power efficiency, the heat dissipation is suppressed, which can be fatal to the image qual ity of ccd sensor. excellent voltage ripple and suppressed heat dissipation will be very beneficial for the c cd system that needs high image quality. features ? built-in 3-channel voltage output option : 15v / 5 .0v / -8v, 12v / 3.3v / -8v ? pwm method ? high power efficiency (80%) ? low heat dissipation ? 9~18v wide operating voltage ? very low ripple voltage noise (less than 20mv) ? high driving current (300ma@vout 3.3v or 5.0v) ? small package size :16pin mlp (qfn) ? simple and low cost external circuit ? built-in protection circuit for external damage application ? b/w ccd camera system ? color ccd camera system ? other ccd image sensor power supply triple dc to dc converter control ic for ccd image sensor
2 IK3301 rev. 01 general description figure 1 shows the simplified block diagram of ik33 01. the device consists of two highly efficient dc- dc converters, a negative charge pump, clock generator to supply clock signals to each circuit and refere nce voltage generator. the 15v supply voltage is generated by up voltage c onverter, which utilizes one external inductor, one external capacitor and two external diodes. the int ernal comparator continuously monitors the output voltage and adjusts it to 15v by controlling pwm (p ulse width modulation) circuit. the 5v supply volta ge is generated by down voltage converter, which utilizes one external inductor, one pfet switch, one externa l capacitor and one external diode. the internal comp arator continuously monitors the output voltage and adjusts it to 5v by controlling pwm circuit. the ?8 v supply voltage is generated by negative charge pu mp. this circuit needs two diodes, two external capacit ors, and one external inductor. the user can adjust the output voltages by changing the feedback resistor r atio for all three output voltages. the reference voltage is generated from internal ba nd-gap reference circuit and almost constant to the temperature and the power supply voltage. as a resu lt, 15v, 5v, and -8v voltage outputs are also const ant to temperature and power supply voltage. block diagram figure 1. block diagram
3 IK3301 rev. 01 pin description for IK3301 (16-qfn) figure 2. package pin-out diagram pin description pwm output for -8v output o vo8 16 power ground for -8v generation (common ground point at the pcb) g pg8 15 power supply for -8v output (common supply at the pcb) p pvcc2 14 nside pwm output for 15v output o vo15 13 power ground for 15v generation (common ground point at the pcb) g pg15 12 pside pwm output for 15v output o vo15p 11 power block power supply for 5v output (common supply at the pcb) p pvcc3 10 pwm output for 5v output o vo5 9 power ground for 5v generation (common ground point a t the pcb) g pg5 8 peak current sense i i pk 7 feedback input3 i v fb3 6 bandgap reference voltage output o bg 5 analog signal block ground (common ground point at the pcb) g v ss 4 analog signal block power supply (common supply at the p cb) p v dd 3 feedback input1 i v fb1 2 feedback input2 i v fb2 1 description i/o, p/g pin name pin no
4 IK3301 rev. 01 absolute maximum ratings and recommand operating con ditions -65 c to +150 c storage temperature range (t s ) -40 c to 85 c operating temperature(t a ) -0.5v to +25.0v voltage on any pin with gnd = 0v (v i ) 9v to 18v power supply voltage vdd, pvcc2, pvcc3 -0.5v to +25.0v power supply voltage vdd, pvcc2, pvcc3 recommand operating conditions absolute maximum ratings electrical characteristics (v dd = 9v~15v, -40 c < t a < 85 c, except as specified) v 12.5 12.0 11.5 12v output voltage vo12 v 3.4 3.3 3.17 3.3v output voltage vo33 v -8.3 -8.0 -7.7 -8v output voltage vo8 v 15.5 15.0 14.5 15v output voltage vo15 v 5.2 5.0 4.8 5v output voltage vo5 ma -- -- 10 v dd, pv cc2, pv cc3 =12.0v output current of -8v output ioutn8 ma -- -- 15 v dd, pv cc2, pv cc3 =12.0v output current of 15v output iout15 ma -- -- 300 v dd, pv cc2, pv cc3 =12.0v output current of 5v output iout5 ma 20 10 -- v dd, pv cc2, pv cc3 =12.0v power supply current i dd units max typ min conditions parameter symbol
5 IK3301 rev. 01 electrical description the standard external components for standard load are shown in figure 4. 1. multi-output generation(-8v & 5v & 15v) IK3301 consists of cmos step-down, step-up, and vol tage-inverting switching regulator, which produces 5v, 15v, and -8v. this device contains an internal temperature compensated bandgap reference, comparator, duty cycle controlled oscillator with c ycle-cycle current limit circuit, and high current output switch with logic gates. three outputs of 5v , 15v, and -8v are adjustable through two external feedback resistors with 2% reference volta ge accuracy. the power efficiency depends on the value and the efficiency of external components , the load current and the target ripple voltage. the minimum efficiency of the 5v voltage generator is 80% with the reference circuit shown in figure 4. the maximum load current of 5v of the ref erence circuit is 300ma, the maximum ripple voltage is 20mv. to save external components, inter nal pch and nch power mos fet are used to generate -8v and 15v. the 5v pch power mos fet is used as external component because of high peak current and package power dissipation. 2. internal bg reference IK3301 generates three outputs which are determined by the internal bandgap reference voltage and the ratio of the feedback resistors. therefore, the out put voltages of 15v, 5v, and -8v are also insensitive of the temperature and power supply var iations. 3. internal oscillator IK3301 has an internal oscillator which charges and discharges the internal timing capacitor using cur rent sourcing and sinking between an upper and lower pre determined threshold voltage. the upper threshold voltage is 1.8v and the lower threshold v oltage is 0.8v. the charging current and discharging current ratio is one to six which will vary depending on running frequency. the oscillator frequency is around 500khz which is dete rmined by the chosen internal capacitor value and charging & discharging current and oscillator a mplitude. internal oscillator
6 IK3301 rev. 01 maximum output voltage of the charge pump figure 3. internal oscillator & maximum output volt age of the charge pump
7 IK3301 rev. 01 functional block diagrams and application circuits figure 4. functional block diagrams and application circuits sr o_ o_o_ o_ c cc c t tt t err_comp err_comp err_comp err_comp c cc c t tt t i ii i pk pkpk pk osc osc osc osc o_ o_o_ o_ c cc c t tt t v vv v bg bgbg bg v vv v bg bgbg bg v vv v fb1 fb1 fb1 fb1 bg bgbg bg ref ref ref ref s q r v vv v fb2 fb2 fb2 fb2 s q r o_ o_o_ o_ c cc c t tt t v vv v fb2 fb2 fb2 fb2 v fb1 i pk v bg v fb3 v dd v ss vo8 pg_5 13 1313 13 pg8 10 1010 10 9 99 9 8 88 8 7 77 7 6 66 6 5 55 5 v fb2 1 11 1 2 22 2 3 33 3 4 44 4 10uh a b a b a b vcc vo15p vo15 pg15 current current current current limit limit limit limit v vv v fb3 fb3 fb3 fb3 vo5 pvcc3 r5 r6 12uh 220uf vo_5v bg v r r r v vo + = 6 6 5 5 _ 56uf 46uh v vv v fb1 fb1 fb1 fb1 r1 r2 bat62/sie 11 1111 11 12 1212 12 v vv v bg bgbg bg v vv v fb2 fb2 fb2 fb2 vo_n_8v bat62/sie r3 r4 56uf bg v r r r v vo + = 4 4 3 8 _ 0.46uh q pvcc2 14 1414 14 15 1515 15 16 1616 16 vo_5v vo_15v bg v r r r v vo + = 2 2 1 15 _ fdfs2p103a v vv v dd dddd dd
8 IK3301 rev. 01 4. functional description in figure 4., during ramping up portion of the cycl e, the and gate input ?a? will be high. if the outpu t voltage of switching regulator is below than target voltage , the and gate input ?b? will be high. this condition will set the latch and cause the ?q? outpu t to be high enabling the driver and output switch to be on (for nfet switch case). when the os cillator reaches its upper threshold, ct will start to discharge and the and gate input will be l ow. the logic level is also connected to an inverter whose output produces a logic ?high? to the reset input of the latch. this condition will cause ?q? to go low, which disables the driver out o utput switch. the comparator output can set the latch only during the ramp-up of ct and can initiate a partial or fu ll on- cycle of output switch conduction. once the compara tor has set the latch, it cannot reset it. the latch will remain set until ct begins ramping down. thus the comparator can initiate the output switch conduction, but cannot stop it and the latch is always reset when ct begins remaining down. the comparator?s output will be ?high? when the outp ut voltage of the switching regulator is above target output voltage. the current limiting is achieved by monitoring the voltage drop across an external sense resistor plac ed in series with supply and the output switch. the volta ge drop developed across this resistor is mornitored by the ipk sense pin. when this voltage be comes grater than presetting offset voltage, the current limit circuit provides an additional cu rrent path to charge the timing capacitor ct, which decreases the time of output switch conduction and reduces the amount of energy stored in the inductor. operation of switching regulator in an ov erload or shorted condition will cause a very short but finite time of output conduction.
9 IK3301 rev. 01 package dimensions (16-qfn) all dimension in mm
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