Series PWMControlledStep-DownDC/DCConverters Input Voltage Range : 2.5V ~20V Applications Output Voltage Range : 1.2V ~ 16V Mobile, Cordless phones Oscillation Frequency Range : 100kHz ~ 600kHz : up to 3.0A Output Current Ceramic Capacitor Compatible Palm top computers, PDAs Portable games Cameras, Digital cameras Laptops MSOP-8A Package 5 GeneralDescription Features The XC9201 series are step-up multiple current and voltage feedback DC/DC controller ICs. Current sense, clock frequencies and amp feedback gain can all be externally regulated. A stable power supply is possible with output currents of up to 3.0A.With output voltage fixed internally, VOUT is selectable in 0.1V steps within a Stable Operations via Current & Voltage Multiple Feedback Unlimited Options for Peripheral Selection Current Protection Circuit Ceramic Capacitor Compatible 1.2V - 16.0V range ( 2.5%). For output voltages outside this range, we recommend the FB version which has a 0.9V internal reference voltage. Using this version, the required output voltage can be set-up using 2 external resistors. Switching frequencies can also be set-up externally within a range of 100~600 kHz and therefore frequencies suited to your particular application can be selected. With the current sense function, peak currents (which flow through the driver transistor and the coil) can be controlled. Soft-start time can be adjusted using external resistors and capacitors. During shutdown (CE pin =L), consumption current can be reduced to as little as 0.5A (TYP.) or less and with U.V.L.O (Under Voltage Lock Out) built-in, the external transistor will be automatically shut off below the regulated voltage. TypicalApplicationCircuit TypicalPerformance Characteristic 22H VOUT:5.0V FOSC:330kHz XP132A11A1SR U3FWJ44N Vss8 2Isen VOUT7 3VIN GAIN6 33m 240k 4CE/SS 94F 0.33F 1F CLK5 40F+220F 10K 470pF 220pF EfficiencyEFFI(%) 100 1EXT 80 60 VIN=5.4V 7.2V 40 10.0V 12.0V 20 15.0V 0 0.1 1 10 100 1000 10000 OutputCurrentIOUTmA 535 XC9201Series PinConfiguration PinAssignment EXT 1 8 VSS Isen 2 7 VOUTFB VIN 3 6 CCGAIN CESS 4 5 CLK PINNUMBER PINNAME FUNCTION 1 EXT Driver 2 Isen CurrentSense ProductClassification 3 VIN PowerInput 4 CESS CE/SoftStart 5 CLK ClockInput 6 CCGAIN PhaseCompensation 7 VOUTFB VoltageSense 8 VSS Ground Ordering Information 5 DESIGNATOR SYMBOL C D Number DESCRIPTION Soft-startexternallyset-up Soft-startexternallyset-up OutputVoltage:Forvoltagesabove10V,seebelow: VOUT FB 10=A,11=B,12=C,13=D,14=E,15=F,16=H e.g.VOUT=2.3Vw=2,e=3VOUT=13.5Vw=D,e=5 FBproductsw=0,e=9fixed AdjustableFrequency MSOP-8A Embossedtape.StandardFeed Embossedtape.ReverseFeed A K R L ThestandardoutputvoltagesoftheXC9201Cseriesare2.5V,3.3V,and5.0V. Voltagesotherthanthoselistedaresemi-custom. MSOP-8A 4.900.10 3.000.10 0.15 +0.08 -0.02 6 3.000.10 0.86 -0.10 +0.20 1.02 -0.21 +0.11 0 (0.65) 536 0.000.20 +0.08 0.30 -0.02 0.530.13 PackagingInformation XC9201 Series Marking qRepresentstheproductseries SYMBOL PRODUCTNAME 1 XC9201***AK* MSOP8A q w e wRepresentstheproducttype,DC/DCconverter SYMBOL TYPE C VOUTCEPIN D FBCEPIN r t y PRODUCTNAME XC9201C**AK* XC9201D09AK* eRepresentsintegralnumberofoutputvoltage,orFBtype SYMBOL VOLTAGE 1 1.X 2 2.X 3 3.X 4 4.X 5 5.X 6 6.X 7 7.X 8 8.X 9 9.X 0 FBproducts PRODUCTNAME XC9201C1*AK* XC9201C2*AK* SYMBOL VOLTAGE PRODUCTNAME XC9201CA*AK* XC9201CB*AK* A 10.X B 11.X XC9201C3*AK* XC9201C4*AK* C 12.X D 13.X XC9201C5*AK* XC9201C6*AK* E 14.X F 15.X XC9201CE*AK* XC9201CF*AK* XC9201C7*AK* XC9201C8*AK* H 16.X XC9201CH*AK* XC9201CC*AK* XC9201CD*AK* 5 XC9201C9*AK* XC9201D09AK* rRepresentsdecimalnumberofoutputvoltage SYMBOL VOLTAGE 0 X.0 3 X.3 XC9201C*0AK* XC9201C*3AK* 9 FBproducts XC9201D09AK* PRODUCTNAME tRepresentsoscillatorfrequeney'scontroltype SYMBOL TYPE PRODUCTNAME A AdjustableFrequency XC9201***AK* 537 XC9201Series BlockDiagram EXTtimming controll logic EXT Current Limit Protection VSS VOUT R1 Verr ISEN Limittercomp. PWM VIN Internal Voltage Regulator R2 MIX CC/GAIN Ierr 2.0V tointernal circuit RampWave, InternalCLK generator Sampling 5 CE/SS ChipEnable, SoftStartup, U.V.L.O. CE,UVLO tointernal circuit CLK Vrefgenerator AbsoluteMaximumRatings 538 RATINGS 0.9V Ta=25 PARAMETER SYMBOL EXTPinVoltage VEXT -0.3VDD0.3 ISENPinVoltage VIsen -0.322 UNITS VINPinVoltage VIN -0.322 CE/SSPinVoltage VCE -0.322 CLKPinVoltage VCLK -0.3VDD0.3 CC/GAINPinVoltage VCC -0.3VDD0.3 VOUT/FBPinVoltage VOUT/FB -0.322 EXTPinCurrent IEXT 100 mA Pd 150 mW ContinuousTotal PowerDissipation OperatingAmbient Temperature Topr -4085 StorageTemperature Tstg -55125 XC9201 Series ElectricalCharacteristics XC9201C25AR Ta=25 PARAMETER SYMBOL OutputVoltage VOUT MaximumOperating Voltage MinimumOperating Voltage CONDITIONS IOUT=300mA VINmax UNITS CIRCUITS MIN. TYP. MAX. 2.438 2.500 2.562 V q 20 - - V q - 2.200 V q 1.400 2.0 V t VIN=3.75V,CE=VIN=VOUT 115 220 A w VIN=20.0V,CE=VIN,VOUT=VSS 130 235 A w ISTB VIN=3.75V,CE=VOUT=VSS 0.5 2.0 A w CLKOscillation Frequency FOSC RT=10.0k,CT=220pF 330 380 kHz e FrequencyInput Stability FOSC 5 % e 5 % e % r % r VINmin U.V.L.O.Voltage VUVLO SupplyCurrent1 IDD1 SupplyCurrent2 IDD2 Stand-byCurrent VINFOSC FrequencyTemperature FOSC Fluctuation TOPRFOSC - EXTvoltage=High 1.0 280 VIN=2.5V20V VIN=3.75V TOPR=-40+85 MaximumDutyCycle MAXDTY VOUT=VSS MinimumDutyCycle MINDTY VOUT=VIN CurrentLimiterVoltage ILIM VINpinvoltage-ISENpinvoltage 90 150 220 mV y ISENCurrent IISEN VIN=3.75V,ISEN=3.75V 4.5 7 13 A y CE"High"Current ICEH CE=VIN=20.0V,VOUT=0V -0.1 0 0.1 A t CE"Low"Current ICEL CE=0V,VIN=20.0V,VOUT=0V -0.1 0 0.1 A t V t 0.2 V t CE"High"Voltage VCEH ExistanceofCLKOscillation, 100 0 0.6 5 VOUT=0V,CEVoltageapplied CE"Low"Voltage VCEL DissapearanceofCLKOscillation, VOUT=0V,CEVoltageapplied EXT"High" ONResistance EXT"Low" ONResistance REXTH EXT=VIN-0.4V,CE=VOUT=VIN*1 27 40 r REXTL EXT=0.4V,CE=VIN,VOUT=VSS*1 24 33 r Efficiency(NOTE1) EFFI % q Soft-startTime TSS ms q CC/GAINPin OutputImpedance RCCGAIN k u 93 ConnectCSSandRSS,CE:0V3.75V 5 10 400 20 VIN=3.75Vunlessspecified *1:Onresistance=0.4V/measurementcurrent NOTE1:EFFI={[(OutputVoltage)x(OutputCurrent)]/[(InputVoltage)x(InputCurrent)]}x100 NOTE2:ThecapacityrangeofthecondenserusedtosettheexternalCLKfrequencyis180300pF 539 XC9201Series XC9201C33AR PARAMETER OutputVoltage MaximumOperating Voltage MinimumOperating Voltage VOUT VINmax U.V.L.O.Voltage VUVLO CONDITIONS IOUT=300mA VINmin MIN. TYP. MAX. 3.218 3.300 3.382 V q 20 - - V q - 2.200 V q 1.400 2.0 V t - EXTvoltage=High 1.0 UNITS CIRCUITS SupplyCurrent1 IDD1 VIN=5.0V,CE=VIN=VOUT 115 220 A w SupplyCurrent2 IDD2 VIN=20.0V,CE=VIN,VOUT=VSS 130 235 A w Stand-byCurrent ISTB VIN=5.0V,CE=VOUT=VSS 0.5 2.0 A w CLKOscillation Frequency FOSC RT=10.0k,CT=220pF 330 380 kHz e Frequency FOSC 5 % e InputStability VINFOSC 5 % e FrequencyTemperature Fluctuation 5 Ta=25 SYMBOL FOSC 280 VIN=2.5V20V VIN=5.0V TOPRFOSC Topr=-40+85 MaximumDutyCycle MAXDTY VOUT=VSS MinimumDutyCycle CurrentLimiter Voltage MINDTY VOUT=VIN ILIM VINpinvoltage-ISENpinvoltage % r 0 % r 220 mV y 100 90 150 ISENCurrent IISEN VIN=5.0V,ISEN=5.0V 4.5 7 13 A y CE"High"Current ICEH CE=VIN=20.0V,VOUT=0V -0.1 0 0.1 A t CE"Low"Current ICEL CE=0V,VIN=20.0V,VOUT=0V -0.1 0 0.1 A t V t 0.2 V t 24 33 r 22 31 r % q ms q k u CE"High"Voltage VCEH ExistanceofCLKOscillation, 0.6 VOUT=0V,CE:Voltageapplied CE"Low"Voltage VCEL DissapearanceofCLKOscillation, VOUT=0V,CE:Voltageapplied EXT"High" ONResistance EXT"Low" ONResistance REXTH EXT=VIN-0.4V,CE=VOUT=VIN*1 REXTL EXT=0.4V,CE=VIN,VOUT=VSS*1 Efficiency(NOTE1) EFFI Soft-startTime TSS CC/GAINPin OutputImpedance 93 ConnectCSSandRSS,CE:0V5.0V 5 RCCGAIN VIN=5.0Vunlessspecified *1:Onresistance=0.4V/measurementcurrent NOTE1:EFFI={[(OutputVoltage)x(OutputCurrent)]/[(InputVoltage)x(InputCurrent)]}x100 NOTE2:ThecapacityrangeofthecondenserusedtosettheexternalCLKfrequencyis180300pF 540 10 400 20 XC9201 Series XC9201C50AR Ta=25 PARAMETER SYMBOL OutputVoltage MaximumOperating Voltage MinimumOperating Voltage VOUT VINmax U.V.L.O.Voltage VUVLO CONDITIONS IOUT=300mA VINmin MIN. TYP. MAX. 4.875 5.000 5.125 V q 20 - - V q - 2.200 V q 1.400 2.0 V t - EXTvoltage=High 1.0 UNITS CIRCUITS SupplyCurrent1 IDD1 VIN=7.5V,CE=VIN=VOUT 115 220 A w SupplyCurrent2 IDD2 VIN=20.0V,CE=VIN,VOUT=VSS 130 235 A w Stand-byCurrent ISTB VIN=7.5V,CE=VOUT=VSS 0.5 2.0 A w CLKOscillation Frequency FOSC RT=10.0k,CT=220pF 330 380 kHz e Frequency FOSC 5 % e InputStability VINFOSC 5 % e FrequencyTemperature FOSC Fluctuation TOPRFOSC 280 VIN=2.5V20V VIN=7.5V TOPR=-40+85 MaximumDutyCycle MAXDTY VOUT=VSS MinimumDutyCycle CurrentLimiter Voltage MINDTY VOUT=VIN ILIM VINpinvoltage-ISENpinvoltage % r 0 % r 220 mV y 100 90 150 ISENCurrent IISEN VIN=7.5V,ISEN=7.5V 4.5 7 13 A y CE"High"Voltage ICEH CE=VIN=20.0V,VOUT=0V -0.1 0 0.1 A t CE"Low"Voltage ICEL CE=0V,VIN=20.0V,VOUT=0V -0.1 0 0.1 A t V t 0.2 V t CE"High"Voltage VCEH ExistanceofCLKOscillation, 0.6 5 VOUT=0V,CEVoltageapplied CE"Low"Voltage VCEL DissapearanceofCLKOscillation, VOUT=0VCEVoltageapplied EXT"High" ONResistance EXT"Low" ONResistance REXTH VEXT=VIN-0.4V,CE=VOUT=VIN*1 21 29 r REXTL VEXT=0.4V,CE=VIN,VOUT=VSS*1 20 27 r Efficiency(NOTE1) EFFI % q Soft-startTime TSS ms q k u CC/GAINPin OutputImpedance 93 ConnectCSSandRSS,CE:0V7.5V 5 RCCGAIN 10 400 20 VIN=7.5Vunlessspecified *1:Onresistance=0.4V/measurementcurrent NOTE1:EFFI={[(OutputVoltage)x(OutputCurrent)]/[(InputVoltage)x(InputCurrent)]}x100 NOTE2:ThecapacityrangeofthecondenserusedtosettheexternalCLKfrequencyis180300pF 541 XC9201Series XC9201D09AR SYMBOL FBVoltage MaximumOperating Voltage MinimumOperating Voltage VINmax U.V.L.O.Voltage VUVLO SupplyCurrent1 IDD1 VFB CONDITIONS IOUT=300mA MIN. TYP. MAX. 0.8775 0.900 0.9225 20 UNITS CIRCUITS V q V q 2.200 V q 1.400 2.0 V t VIN=4.0V,CE=VIN=FB 115 220 A w VINmin EXTvoltage=High 1.0 SupplyCurrent2 IDD2 VIN=20.0V,CE=VIN,FB=VSS 130 235 A w Stand-byCurrent ISTB VIN=4.0V,CE=FB=VSS 0.5 2.0 A w CLKOscillation Frequency FOSC RT=10.0k,CT=220pF 330 380 kHz e 5 % e 5 % e % r Frequency FOSC InputStability VINFOSC FrequencyTemperature Fluctuation 5 Ta=25 PARAMETER FOSC VIN=2.5V20V VIN=4.0V TOPRFOSC TOPR=-40+85 MaximumDutyCycle MAXDTY FB=VSS MINDTY FB=VIN MinimumDutyCycle CurrentLimiter Voltage 280 ILIM VINpinvoltage-ISENpinvoltage 100 90 150 0 % r 220 mV y y ISENCurrent IISEN VIN=4.0V,ISEN=4.0V 4.5 7 13 A CE"High"Current ICEH CE=VIN=20.0V,FB=0V -0.1 0 0.1 A t CE"Low"Current ICEL CE=0V,VIN=20.0V,FB=0V -0.1 0 0.1 A t CE"High"Voltage VCEH V t 0.2 V t 27 40 r 24 34 r % q ms q k u ExistanceofCLKOscillation, 0.6 FB=0V,CEVoltageapplied CE"Low"Voltage VCEL DissapearanceofCLKOscillation, FB=0VCEVoltageapplied EXT"High" ONResistance EXT"Low" ONResistance REXTH EXT=VIN-0.4V,CE=FB=VIN*1 REXTL EXT=0.4V,CE=VIN,FB=VSS*1 Efficiency(NOTE1) EFFI Soft-startTime TSS CC/GAINPin OutputImpedance 93 ConnectCSSandRSS,CE:0V4.0V 5 RCCGAIN VIN=4.0Vunlessspecified Externalcomponents:RFB1=200k,RFB2=100k,CFB=82pF *1:Onresistance=0.4V/measurementcurrent NOTE1:EFFI={[(OutputVoltage)x(OutputCurrent)]/[(InputVoltage)x(InputCurrent)]}x100 NOTE2:ThecapacityrangeofthecondenserusedtosettheexternalCLKfrequencyis180300pF 542 10 400 20 XC9201 Series TypicalApplicationCircuits XC9201C33AKR 22H PMOS 1 EXT VSS 8 2 Isen VOUT 7 3 VIN 4 CE/SS 3.3V 1.5A 50m SD CC/GAIN 6 240k 7.2V 47F 470pF CLK 5 220pF 1F 30k 47F(OS)or 10F(ceramic)x4 0.22F PMOS Coil : XP132A11A1SR(TOREX) : 22H(CR105 SUMIDA) Resistor : 50m for Isen (NPR1 KOWA), 30k(trimmer) for CLK, 240k for SS 5 Capacitors : 220pF( ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.22F(any) for SS,1F(ceramic) for Bypass 47F(OS) or 10F(ceramic) x 4 for CL, 47F(tantalum) for CIN SD : U3FWJ44N(TOSHIBA) XC9201C50AKR 22H 5.0V 1.5A PMOS 1 EXT VSS 8 2 Isen VOUT 7 3 VIN 4 CE/SS 20m SD CC/GAIN 6 240k CLK 5 470pF 12.0V 47F 0.33F 1F +220F 220pF PMOS Coil : XP132A11A1SR(TOREX) : 22H(CDRH127 SUMIDA) Resistor : 20m for Isen (NPR1 KOWA), 30k(trimmer) for CLK, 240k for SS 30k 47F(OS) +220F(any) Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.33F(any) for SS, 1F(ceramic) for Bypass 47F(OS)+220F(any) for CL, 47F(tantalum)+220F(any) for CIN SD : U3FWJ44N(TOSHIBA) 543 XC9201Series XC9201D09AKR 22H 39pF PMOS 1 EXT VSS 8 2 Isen VOUT 7 3 VIN 4 CE/SS 2.5V 3A 20m SD CLK 5 7.2V 47F 0.22F +220F 220k CC/GAIN 6 240k 5 390k 220pF 1F 470pF 47uF(OS) +220F(any) 30k PMOS Coil : XP132A11A1SR(TOREX) : 22H(CDRH127 SUMIDA) Resistors : 20m for Isen (NPR1 KOWA), 30k(trimmer) for CLK, 240k for SS, 390k for Output Voltage 100k(trimmer) for Output Voltage Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.22F(any) for SS, 1F(ceramic) for Bypass 39pF(ceramic) for FB,47F(OS) for CL,47F (tantalum)+220F(any) for CIN SD : U3FWJ44N(TOSHIBA) XC9201D09AKR 47H 56pF PMOS 1 EXT VSS 8 2 Isen FB 7 3 VIN 4 CE/SS 270k 50m SD CLK 5 20V 47F 0.47F 1F 22k CC/GAIN 6 240k 220pF 470pF 30k PMOS Coil : XP132A11A1SR(TOREX) : 47H(CR105 SUMIDA) Resistor : 50m for Isen (NPR1 KOWA), 30k(trimmer) for CLK, 240k for SS, 270k for Output Voltage 22k(trimmer) for Output Voltage Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.47F(any) for SS, 1F(ceramic) for Bypass 100pF(ceramic) for FB, 47F(OS) +220F(any) for CL, 47F(tantalum)+220F(any) for CIN SD 544 12V 1.5A : U3FWJ44N(TOSHIBA) 47F(OS) +220F XC9201 Series OperationDescription Step-down DC/DC converter controllers of the XC9201series carry out pulse width modulation (PWM) according to the multiple feedback signals of the output voltage and coil current. The internal circuits consist of different blocks that operate at VIN or the stabilized power (2.0 V) of the internal regulator. The output setting voltage of type C controller and the FB pin voltage (Vref = 0.9 V) of type D controller have been adjusted and set by laser-trimming. <Clock> With regard to clock pulses, a capacitor and resistor connected to the CLK pin generate ramp waveforms whose top and bottom are 0.7 V and 0.15 V, respectively. The frequency can be set within a range of 100 to 600 kHz externally (refer to the "Functional Settings" section for further information). The clock pulses are processed to generate a signal used for synchronizing internal sequence circuits. <Verr amplifier> The Verr amplifier is designed to monitor the output voltage. A fraction of the voltage applied to internal resistors R1, R2 in the case of a type C controller, and the voltage of the FB pin in the case of a type D controller, are fed back and compared with the reference voltage. In response to feedback of a voltage lower than the reference voltage, the output voltage of the Verr amplifier increases. The output of the Verr amplifier enters the mixer via resistor (RVerr). This signal works as a pulse width control signal during PWM operations. By connecting an external capacitor and resistor through the CE/GAIN pin, it is possible to set the gain and frequency characteristics of Verr amplifier signals (refer to the "Functional Settings" section for further information). 5 <Ierr amplifier> The Ierr amplifier monitors the coil current. The potential difference between the VIN and Isen pins is sampled at each switching operation. Then the potential difference is amplified or held, as necessary, and input to the mixer. The Ierr amplifier outputs a signal ensuring that the greater the potential difference between the VIN and Isen pins, the smaller the switching current. The gain and frequency characteristics of this amplifier are fixed internally. <Mixer and PWM> The mixer modulates the signal sent from Verr by the signal from Ierr. The modulated signal enters the PWM comparator for comparison with the sawtooth pulses generated at the CLK pin. If the signal is greater than the sawtooth waveforms, a signal is sent to the output circuit to turn on the external switch. <Current Limiter> The current flowing through the coil is monitored by the limiter comparator via the VIN and Isen pins. The limiter comparator outputs a signal when the potential difference between the VIN and Isen pins reaches 150 mV or more. This signal is converted to a logic signal and handled as a DFF reset signal for the internal limiter circuit. When a reset signal is input, a signal is output immediately at the EXT pin to turn off the MOS switch. When the limiter comparator sends a signal to enable data acceptance, a signal to turn on the MOS switch is output at the next clock pulse. If at this time the potential difference between the VIN and Isen pins is large, operation is repeated to turn off the MOS switch again. DFF operates in synchronization with the clock signal of the CLK pin. Limitersignal /RESET PWM/PFMswitchingsignal CLKsyncsignal D CLK Q OutputsignaltoEXTpin PWM/PFMswitchinigsignal <Soft Start> The soft start function is made available by attaching a capacitor and resistor to the CE/SS pin. The Vref voltage applied to the Verr amplifier is restricted by the start-up voltage of the CE/SS pin. This ensures that the Verr amplifier operates with its two inputs in balance, thereby preventing the ON-TIME signal from becoming stronger than necessary. Consequently, soft start time needs to be set sufficiently longer than the time set to CLK. The start-up time of the CE/SS pin equals the time set for soft start (refer to the "Functional Settings" section for further information). The soft start function operates when the voltage at the CE/SS pin is between 0V to 1.55V. If the voltage at the CE/SS pin doesn't start from 0V but from a mid level voltage when the power is switched on, the soft start function will become ineffective and the possibilities of large inrush currents and ripple voltages occurring will be increased. Undervoltage Lock Out (U.V.L.O.) is also provided. This function is activated to turn off the MOS switch attached to the EXT pin when the input voltage (VIN) decreases to approximately 1.4 V or below. The purpose of this function is to keep the external MOS switch from turning on when a voltage at which the IC operates unstably is applied. U.V.L.O. also restricts signals during soft start so that the external MOS switch does not turn on until the internal circuitry becomes stable. 545 XC9201Series Functional Settings 1. Soft Start CE and soft start (SS) functions are commonly assigned to the CE/SS pin. The soft start function is effective until the voltage at the CE pin reaches approximately 1.55 V rising from 0 V. Soft start time is approximated by the equation below according to values of Vcont, RSS, and CSS. T=-Css x Rss x ln((Vcont-1.55)/Vcont) Example: When Css=0.1F,Rss=470k, and Vcont=5V, T=-0.1e-6 x 470e3 x In((5-1.55)/5)=17.44ms. CE/SSpin InsidetheIC Rss Vcont CE, UVLO Css Vrefcircuit Set the soft start time to a value sufficiently longer than the period of a clock pulse. 5 > Circuit example 1: N-ch open drain Vcont InsidetheIC Rss CE/SSpin ON/OFFsignal Css > Circuit example 2: CMOS logic (low current dissipation) Vcont InsidetheIC Rss ON/OFFsignal CE/SSpin Css > Circuit example 3: CMOS logic (low current dissipation), quick off Vcont InsidetheIC Rss ON/OFFsignal CE/SSpin Css 546 ToVerramplifier XC9201 Series 2.Oscillation Frequency The oscillation frequency of the internal clock generator is approximated by the following equation according to the values of the capacitor and resistor attached to the CLK pin. To stabilize the IC's operation, set the oscillation frequency within a range of 100kHz to 600kHz. Select a value for Cclk within a range of 180pF to 300pF and fix the frequency based on the value for Rclk. f=1/ (-Cclk x Rclk x ln 0.26) Example: When Cclk = 220 pF and Rclk = 10 k, f = 1/(-220e-12 x 10e3 x ln(0.26)) = 337.43 kHz. InsidetheIC CLKpin Rclk Cclk CLKGenerater 3.Gain and Frequency Characteristics of the Verr Amplifier The gain at output and frequency characteristics of the Verr amplifier are adjusted by the values of capacitor and resistor attached to the CC/GAIN pin. It is generally recommended to attach a C_GAIN of 220 to 1,000 pF without an R_GAIN. The greater the C_GAIN value, the more stable the phase and the slower the transient response. When using the IC with R_GAIN connected, it should be noted that if the R_GAIN resistance value is too high, abnormal oscillation may occur during transient response time. The size of R_GAIN should be carefully determined and connected. 5 InsidetheIC CC/GAINpin VOUT/FB Verr CC RGAIN Vref RVerr 4.Current Limiting The current limiting value is approximated by the following equation according to resistor RSEN inserted between the VIN and ISEN pins. Double function, current FB input and current limiting, is assigned to the ISEN pin. The current limiting value is approximated by the following equation according to the value for RSEN. ILpeak_limit = 0.15 / RSEN Example: When RSEN = 100 m, ILpeak_limit = 0.15 / 0.1 = 1.5 A InsidetheIC Isenpin Rsen Limitersignal VINpin Comparatorwith 150-mVoffset Because of the feedback at the internal error amp with this IC (which is brought about as a result of the phase compensation of the voltage generated at RSEN, which is in turn caused by current flowing through the coil when the PMOS is working.), should the value of the RSEN resistor be too large, the feedback signal will also increase and intermittent oscillation may occur. We therefore recommend that you carefully check the value for RSEN should you have a problem with oscillation. During normal operations, a voltage will be generated at RSEN as a result of the coil's peak current. Please ensure that this voltage is less than the current limit voltage which is 90mV (min.). For RSEN resistor's rated power, please refer to the note on the RSEN resistor on page 18. 547 XC9201Series 5. FB Voltage and Cfb With regard to the XC9201D series, the output voltage is set by attaching externally divided resistors. The output voltage is determined by the equation shown below according to the values of Rfb1 and Rfb2. In general, the sum of Rfb1 and Rfb2 should be 1 MEG or less. VOUT = 0.9 x (Rfb1 + Rfb2)/Rfb2 The value of Cfb (phase compensation capacitor) is approximated by the following equation according to the values of Rfb1 and fzfb. The value of fzfb should be 10 kHz, as a general rule. Cfb = 1/(2 x x Rfb1 x fzfb) Example: When Rfb1 = 455 k and Rfb2 = 100 k : VOUT = 0.9 x (455 k + 100 k)/100 k = 4.995 V : Cfb = 1/(2 x x 455 k x 10 k) = 34.98 pF. InsidetheIC Outputvoltage Cfb Rfb1 FBpin Verr Rfb2 5 0.9V Verramplifier Directionsforuse Application Notes 1. The 9201 series are designed for use with an output ceramic capacitor. If, however, the potential difference between input and output is too large, a ceramic capacitor may fail to absorb the resulting high switching energy and oscillation could occur on the output side. If the inputoutput potential difference is large, connect an electrolytic capacitor in parallel to compensate for insufficient capacitance. 2. The EXT pin of the XC9201 series is designed to minimize the through current that occurs in the internal circuitry. However, the gate drive of external PMOS has a low impedance for the sake of speed. Therefore, if the input voltage is high and the bypass capacitor is attached away from the IC, the charge/discharge current to the external PMOS may lead to unstable operations due to switching operation of the EXT pin. As a solution to this problem, place the bypass capacitor as close to the IC as possible, so that voltage variations at the VIN and VSS pins caused by switching are minimized. If this is not effective, insert a resistor of several to several tens of ohms between the EXT pin and PMOS gate. Remember that the insertion of a resistor slows down the switching speed and may result in reduced efficiency. 3. A PNP transistor can be used in place of PMOS. If using a PNP transistor, insert a resistor (Rb) and capacitor (Cb) between the EXT pin and the base of the PNP transistor in order to limit the base current without slowing the switching speed. Adjust Rb in a range of 500 to 1k according to the load and hFE of the transistor. Use a ceramic capacitor for Cb, complying with Cb < 1/ ( 2 x x Rb x Fosc x 0.7), as a rule. InsidetheIC EXTpin Rb VIN Cb 4. This IC incorporates a limit comparator to monitor the voltage produces across the RSEN resistor at the current peak of the coil. It functions as a limiter when, for example, the output is short-circuited. In such a case, the limit comparator senses that the voltage across the RSEN resistor has reached a current-limiting voltage (typically 150mV) and outputs a signal to turn off the external transistor. After sensing a current-limiting voltage, the limit comparator typically takes 200nsec before it turns off the external resistor. During this time, the voltage across the RSEN resistor can exceed the current-limiting voltage, especially when the difference between the input voltage and the output voltage is large and the coil inductance is small. Therefore, exercise great care in selecting absolute maximum ratings of the external transistor, coil, and Schottky diode. 5. If the difference between the input voltage and the output voltage is large or small, the switching ON time or OFF time of this IC becomes short and actual operation can be critically influenced by values of peripheral components 'inductance of coil, resistance of CLK connection, capacitance of capacitor, etc.) Before use, it is recommended to evaluate this IC thoroughly with an actual unit. 548 XC9201 Series Recommended Pattern Layout q In order to stabilize VDD's voltage level, we recommend that a by-pass condenser (CDD) be connected as close as possible to the VIN & VSS pins. w In order to stabilize the GND voltage level which can fluctuate as a result of switching, we suggest that C_CLK's, R_CLK's & C_GAIN's GND be separated from Power GND and connected as close as possible to the VSS pin (by-pass condenser, CDD). Please use a multi layer board and check the wiring carefully. Pattern Layout Examples XC9201 Series (D Series) 2 layer Evaluation Board P-MOS L CDD CFB RFB1 SD 1 5 2 6 3 7 4 8 VDDLine CL ICGND RSEN CGAIN RSS VIN CIN RFB2 5 PowerGND RCLK CSS CCLK ThroughHole 1 5 2 6 3 7 4 8 RCLK,CCLK,CGAIN,RFB2 GND ThroughHole 549 XC9201Series 1 layer Evaluation Board P-MOS L CDD CFB SD 1 5 2 6 3 7 4 8 VDDLine RFB1 CL ICGND RSEN PowerGND RSS VIN CIN CSS 5 RFB2 RCLK CCLK CGAIN Notes on Use Ensure that the absolute maximum ratings of the external components and the XC9201 DC/DC IC itself are not exceeded. We recommend that sufficient counter measures are put in place to eliminate the heat that may be generated by the external P-MOSFET as a result of switching losses. Try to use a P-MOSFET with as small a gate capacitance as possible in order to avoid overly large output spike voltages that may occur (such spikes occur in proportion to gate capacitance). The performance of the XC9201 DC/DC converter is greatly influenced by not only its own characteristics, but also by those of the external components it is used with. We recommend that you refer to the specifications of each component to be used and take sufficient care when selecting components. Wire external components as close to the IC as possible and use thick, short connecting wires to reduce wiring impedance. In particular, minimize the distance between the by-pass capacitor and the IC. Make sure that the GND wiring is as strong as possible as variations in ground potential caused by ground current at the time of switching may result in unstable operation of the IC. Specifically, strengthen the ground wiring in the proximity of the VSS pin. External Components RSENSE Resistor A low value resistor is defined as a resistor with a 10 value or lower. For RSENSE, the XC9201 series uses a resistor with a value of either 50m or 100m. Although resistors for RSENSE are classified as low resistance chip resistors or current limit resistors (which may give the impression that the RSENSE resistor is expensive), it is not necessary to use expensive low resistance chip resistors as general purpose chip resistors with values of 50m or 100m will do the job just as well. When choosing the RSENSE resistor, it is important to confirm the resistor's power consumption which can be done using the following equation: W (Power Consumption) =I (Current) x V (Voltage) =I (Current) x I (Current) x R (Resistance) It is recommended that a resistor which has a power rating of more than 3 times the power consumption of RSENSE be selected (refer to the example given below) : (ex.) RSENSE = 100m, I = 1A I = 1A RSENSE = 100m (0.1) Power supply W = 1 x 1 x 0.1 = 0.1 [W] 550 0.5W, 100m resistor should be used XC9201 Series TestCircuits Fig.1(FBType) Fig.1(VOUTType) 47H 22H PMOS PMOS SD 1EXT Vss8 2Isen VOUT7 SD 3VIN 1F RL GAIN6 4CE/SS CLK5 47F 2Isen Vss8 FB7 100m 100m RSS RFB1 CFB 1EXT 10K 220pF 3VIN 240k 1F 20F CSS V RFB2 GAIN6 47F 470pF 20K 470pF V RL 4CE/SS CLK5 22F 165pF 0.047F XC9201C25ARSS188kCSS0.1F XC9201C33ARSS270kCSS0.1F XC9201C50ARSS430kCSS0.1F Fig.2 Fig.3 1EXT 1EXT Vss8 3VIN 5 Vss8 2IsenVOUT/FB7 2IsenVOUT/FB7 3VIN GAIN6 GAIN6 4CE/SS CLK5 A 4CE/SS CLK5 220pF Fig.4 OSC 10K 0.1F 10K 0.1F 220pF Fig.5 H 1EXT A 1EXT Vss8 L 3VIN 3VIN GAIN6 0.1F 4CE/SS CLK5 A 220pF 10K 220pF Fig.6 V Fig.7 1EXT 1EXT Vss8 3VIN A 3VIN GAIN6 4CE/SS CLK5 0.1F Vss8 2IsenVOUT/FB7 2IsenVOUT/FB7 V GAIN6 4CE/SS CLK5 10K 0.1F Vss8 2IsenVOUT/FB7 V 2IsenVOUT/FB7 GAIN6 4CE/SS CLK5 220pF 0.1F 1M V 10K 551 XC9201Series TypicalPerformance Characteristics XC9201D09AKR (1) OUTPUT VOLTAGE vs. OUTPUT CURRENT VOUT1.5V,FOSC:330kHz VOUT3.3V,FOSC:330kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 3.5 5 OutputVoltage:VOUT(V) OutputVoltage:VOUT(V) 1.7 1.6 1.5 1.4 VIN=3.3V 5.0V 7.2V 3.4 3.3 VIN=4.0V 6.0V 8.0V 10.0V 12.0V 3.2 3.1 1.3 0.1 1 10 100 1000 0.1 10000 10 100 1000 10000 OutputCurrent:IOUT(mA) OutputCurrent:IOUT(mA) VOUT5.0V,FOSC:330kHz VOUT12.0V,FOSC:100kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR L=68H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=10F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP132A11C0PR 12.2 5.1 5.0 VIN=8.0V 10.0V 12.0V 15.0V 4.9 OutputVoltage:VOUT(V) 5.2 OutputVoltage:VOUT(V) 1 12.1 12.0 11.9 VIN=18.0V 4.8 11.8 0.1 1 10 100 1000 OutputCurrent:IOUT(mA) 552 10000 0.1 1 10 100 1000 OutputCurrent:IOUT(mA) 10000 XC9201 Series (2) EFFICIENCY vs. OUTPUT CURRENT VOUT1.5V,FOSC:330kHz VOUT3.3V,FOSC:330kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 100 80 80 Efficiency:EFFI(%) Efficiency:EFFI(%) CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 100 60 VIN=3.3V 40 5.0V 20 60 6.0V 40 VIN=4.0V 8.0V 10.0V 20 7.2V 12.0V 0 0 0.1 1 10 100 1000 10000 0.1 OutputCurrent:IOUT(mA) 1 10 100 1000 10000 OutputCurrent:IOUT(mA) 5 VOUT5.0V,FOSC:330kHz VOUT12.0V,FOSC:100kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) L=68H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=10F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP132A11C0PR 100 100 80 80 60 Efficiency:EFFI(%) Efficiency:EFFI(%) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 10.0 40 VIN=8.0V 12.0V 15.0V 20 60 40 20 VIN=18.0V 0 0 0.1 1 10 100 1000 OutputCurrent:IOUT(mA) 10000 0.1 1 10 100 1000 10000 OutputCurrent:IOUT(mA) 553 XC9201Series (3) RIPPLE VOLTAGE vs. OUTPUT CURRENT VOUT1.5V,FOSC:330kHz VOUT3.3V,FOSC:330kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),CD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 100 VIN=3.3V 5.0V 7.2V 80 RippleVoltage:Vr(mVp-p) RippleVoltage:Vr(mVp-p) 100 60 40 20 0 10.0V 80 12.0V 8.0V 60 6.0V 40 VIN=4.0V 20 0 0.1 1 10 100 1000 10000 0.1 OutputCurrent:IOUT(mA) 5 1 10 100 1000 10000 OutputCurrent:IOUT(mA) VOUT5.0V,FOSC:330kHz VOUT12.0V,FOSC:100kHz L=22H,CL=40F(Ceramic),CIN=30F(Ceramic) L=68H,CL=40F(Ceramic),CIN=30F(Ceramic) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR RSEN=50m,CDD=10F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP132A11C0PR 100 100 15.0V 12.0V 60 10.0V VIN=8.0V 40 20 RippleVoltage:Vr(mVp-p) RippleVoltage:Vr(mVp-p) VIN=18.0V 80 80 60 40 20 0 0 0.1 1 10 100 1000 0.1 10000 OutputCurrent:IOUT(mA) 10 100 1000 10000 VOUT1.5V,FOSC:330kHz VOUT3.3V,FOSC:330kHz L=22H,CL=47F(Tantalum),CIN=47F(Tantalum) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR L=22H,CL=47F(Tantalum),CIN=47F(Tantalum) RSEN=50m,CDD=1F(Ceramic),SD:U3FWJ44N CGAIN=470pF(Ceramic),Tr:XP162A11C0PR 100 80 RippleVoltage:Vr(mVp-p) 100 RippleVoltage:Vr(mVp-p) 1 OutputCurrent:IOUT(mA) 7.2V 60 VIN=3.3V 5.0V 40 20 12.0V 80 8.0V 10.0V 6.0V 60 VIN=4.0V 40 20 0 0 0.1 1 10 100 1000 OutputCurrent:IOUT(mA) 10000 0.1 1 10 100 1000 10000 OutputCurrent:IOUT(mA) *Note: If the input and output voltage differential is large or small, the time of ON and Off switching will be shorten. This gives external components such as inductance value of coil, connecting a resistor to CLK, condenser, will critically influence the actual operation. 554