XC9201DC0AKL

Torex Semiconductor

PWM Controlled Step-Down DC/DC Converters

Manufacturer: Torex Semiconductor

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PWM Controlled Step-Down DC/DC Converters Series 535 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 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 (Under Voltage Lock Out) built-in, the external transistor will be automatically shut off below the regulated voltage. ■General Description GStable Operations via Current & Voltage Multiple Feedback GUnlimited Options for Peripheral Selection GCurrent Protection Circuit GCeramic Capacitor Compatible GMobile, Cordless phones GPalm top computers, PDAs GPortable games GCameras, Digital cameras GLaptops ■Features ■Applications NInput Voltage Range : 2.5V ~20V NOutput Voltage Range : 1.2V ~ 16V NOscillation Frequency Range : 100kHz ~ 600kHz NOutput Current : up to 3.0A NCeramic Capacitor Compatible 100 0.1 100 1000 10000 Output Current：IOUT（mA）Efficiency：EFFI (%) 7.2V 15.0V VIN=5.4V 10.0V 12.0V 22μH 10KΩ220pF CLK 5

1 EXT

2 Isen

3 VIN

4 CE/SS

40μF+220μF 33mΩXP132A11A1SR U3FWJ44N 1μF 240kΩ0.33μF 94μF ■Typical Application Circuit ■Typical Performance Characteristic VOUT:5.0V FOSC:330kHz 05S_1XC9201/9202新規 02.09.12 15:16 ページ 535

■Packaging Information GMSOP-8A XC9201Series 536 ■Pin Configuration ■Pin Assignment ■Product Classification GOrdering Information EXT Isen VIN CE／SS CC／GAIN CLK VOUT／FB VSS PIN NUMBER PIN NAME FUNCTION EXT Driver Isen Current Sense VIN Power Input CE／SS CE/Soft Start CLK Clock Input CC／GAIN Phase Compensation VOUT／FB Voltage Sense VSS Ground ＸＣ９２０１DESIGNATOR SYMBOL

DESCRIPTION

C VOUT D Number FB A K R Embossed tape. Standard Feed Embossed tape. Reverse Feed L Output Voltage : For voltages above 10V, see below : 10=A, 11=B, 12=C, 13=D, 14=E, 15=F, 16=He.g. VOUT=2.3V → w=2, e=3 VOUT=13.5V → w=D, e=5FB products → w=0, e=9 fixed Soft-start externally set-up Soft-start externally set-up MSOP-8A Adjustable Frequency 3.00±0.10 4.90±0.10 3.00±0.10 0.53±0.13 0～ 6ﾟ0.00～0.20 0.30 +0.08 -0.02 1.02 0.86 +0.11 -0.10 +0.20 -0.21 0.15 +0.08 -0.02 (0.65) 05S_1XC9201/9202新規 02.09.12 15:16 ページ 536

■Marking q Represents the product series SYMBOL PRODUCT NAME XC9201***AK* w Represents the product type, DC/DC converter SYMBOL C PRODUCT NAME D TYPE VOUT、CE PIN FB、CE PIN e Represents integral number of output voltage,or FB type SYMBOL PRODUCT NAME VOLTAGE 1. X 2. X 3. X 4. X 5. X 6. X 7. X 8. X 9. X FB products SYMBOL A PRODUCT NAME B VOLTAGE 10. X 11. X C 12. X D 13. X E 14. X F 15. X H 16. X r Represents decimal number of output voltage SYMBOL PRODUCT NAME VOLTAGE X. 0 X. 3 FB products t Represents oscillator frequeney's control type SYMBOL A PRODUCT NAME XC9201***AK* TYPE Adjustable Frequency MSOP8A q w e r t y XC9201C**AK* XC9201D09AK* XC9201C1*AK* XC9201C2*AK* XC9201C3*AK* XC9201C4*AK* XC9201C5*AK* XC9201C6*AK* XC9201C7*AK* XC9201C8*AK* XC9201C9*AK* XC9201D09AK* XC9201CA*AK* XC9201CB*AK* XC9201CC*AK* XC9201CD*AK* XC9201CE*AK* XC9201CF*AK* XC9201CH*AK* XC9201C*0AK* XC9201C*3AK* XC9201D09AK* 05S_1XC9201/9202新規 02.09.12 15:16 ページ 537

■Absolute Maximum Ratings ■Block Diagram EXT ISEN VIN CE/SS VSS VOUT CC/GAIN CLK Ramp Wave,Internal CLKgenerator Chip Enable,Soft Start up,U.V.L.O. Verr PWM Ierr InternalVoltageRegulator EXT timmingcontrolllogic CurrentLimitProtection Limitter comp. Vref generator CE,UVLOto internalcircuit 0.9V Sampling MIX 2.0Vto internalcircuit PARAMETER EXT Pin Voltage SYMBOL R A T I N G S UNITS －0.3～＋22 ＶISEN Pin Voltage VIN Pin Voltage CE/SS Pin Voltage CLK Pin Voltage VOUT/FB Pin Voltage EXT Pin Current Storage Temperature VEXT VIsen VIN VCE VCLK VOUT/FB IEXT Tstg －0.3～VDD＋0.3 －0.3～＋22 －0.3～＋22 －0.3～VDD＋0.3 －0.3～＋22 ±100 －55～＋125 ＶＶＶＶＶmA Continuous Total Power Dissipation Pd 150 mW Operating Ambient Temperature Topr －40～＋85 ℃℃Ta=25℃CC/GAIN Pin Voltage VCC －0.3～VDD＋0.3 Ｖ05S_1XC9201/9202新規 02.09.12 15:16 ページ 538

■Electrical Characteristics XC9201C25AR VIN = 3.75V unless specified*1 : On resistance = 0.4V / measurement current NOTE1 : EFFI = {[(Output Voltage) x (Output Current)] ÷ [(Input Voltage) x (Input Current)]} x 100NOTE2 : The capacity range of the condenser used to set the external CLK frequency is 180 ∼ 300pF Ta=25℃PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNITS Maximum Operating Voltage Minimum Operating Voltage CLK Oscillation Frequency Supply Current 1 Stand-by Current Frequency Temperature Fluctuation Maximum Duty Cycle Minimum Duty Cycle VINmax Output Voltage VOUT VINmin IDD1 ISTB FOSC Frequency Input Stability ΔFOSC ΔVIN･FOSC ΔFOSC ΔTOPR･FOSC MAXDTY MINDTY Current Limiter Voltage ISEN Current ILIM IISEN CE "High" Current CE "Low" Current ICEH ICEL CE "High" Voltage VCEH EXT voltage = High VIN=3.75V, CE=VIN=VOUT VIN=20.0V, CE=VIN, VOUT=VSS VIN=3.75V, CE=VOUT=VSS RT=10.0kΩ, CT=220pF VIN=2.5V～20V TOPR=－40～+85℃VIN=3.75V IOUT=300mA VOUT=VSS VOUT=VIN VIN pin voltage - ISEN pin voltage VIN=3.75V, ISEN=3.75V CE=VIN=20.0V, VOUT=0V CE=0V, VIN=20.0V, VOUT=0V Existance of CLK Oscillation, VOUT=0V, CE：Voltage applied Dissapearance of CLK Oscillation, VOUT=0V, CE：Voltage applied EXT=VIN－0.4V, CE=VOUT=VIN *1 EXT=0.4V, CE=VIN, VOUT=VSS *1 Connect CSS and RSS, CE : 0V → 3.75V 2.438 －1.0 280 100 4.5 －0.1 －0.1 0.6 2.500 －－1.400115 1300.5330±5 ±5150 002.562 －2.200 2.0 220 235 2.0 380 220 0.1 0.1 V V V V μA μA μA kHz mV μA μA μA V CE "Low" Voltage VCEL 0.2 V EXT "High"ON Resistance REXTH 2740 ΩEXT "Low" ON Resistance REXTL 2433 ΩEfficiency (NOTE1) EFFI 93% Soft-start Time TSS 1020 ms CC/GAIN Pin Output Impedance RCCGAIN 400kΩCIRCUITS q q q t w w w e e e r r y y t t t t r r q q u Supply Current 2 IDD2 U.V.L.O. Voltage VUVLO 05S_1XC9201/9202新規 02.09.12 15:16 ページ 539

VIN = 5.0V unless specified*1 : On resistance = 0.4V / measurement current NOTE1 : EFFI = {[(Output Voltage) x (Output Current)] ÷ [(Input Voltage) x (Input Current)]} x 100NOTE2 : The capacity range of the condenser used to set the external CLK frequency is 180 ∼ 300pF Ta=25℃PARAMETER SYMBOL CONDITIONS UNITS Maximum OperatingVoltage Minimum OperatingVoltage Supply Current 1 Stand-by Current Frequency Temperature Fluctuation Maximum Duty Cycle Minimum Duty Cycle VINmax Output Voltage VOUT VINmin IDD1 ISTB CLK Oscillation Frequency FOSC Frequency Input Stability ΔFOSC ΔVIN･FOSC ΔFOSC ΔTOPR･FOSC MAXDTY MINDTY Current LimiterVoltage ISEN Current ILIM IISEN CE "High" Current CE "Low" Current ICEH ICEL CE "High" Voltage VCEH EXT voltage = High VIN=5.0V, CE=VIN=VOUT VIN=20.0V, CE=VIN, VOUT=VSS VIN=5.0V, CE=VOUT=VSS RT=10.0kΩ, CT=220pF VIN=2.5V～20V Topr=－40～+85℃VIN=5.0V IOUT=300mA VOUT=VSS VOUT=VIN VIN pin voltage - ISEN pin voltage VIN=5.0V, ISEN=5.0V CE=VIN=20.0V, VOUT=0V CE=0V, VIN=20.0V, VOUT=0V Existance of CLK Oscillation, VOUT = 0V, CE : Voltage applied Dissapearance of CLK Oscillation, VOUT = 0V, CE : Voltage applied EXT=VIN - 0.4V, CE=VOUT=VIN *1 EXT=0.4V, CE=VIN, VOUT=VSS *1 Connect CSS and RSS, CE : 0V → 5.0V 3.218 －1.0 280 100 4.5 －0.1 －0.1 0.6 3.300 －－1.400115 1300.5330±5 ±5150 003.382 －2.200 2.0 220 235 2.0 380 220 0.1 0.1 V V V V μA μA μA kHz mV μA μA μA V CE "Low" Voltage VCEL 0.2 V EXT "High" ON Resistance EXT "Low" ON Resistance CC/GAIN Pin Output Impedance REXTH 2433 ΩREXTL 2231 ΩEfficiency (NOTE1) EFFI 93% Soft-start Time TSS 1020 ms RCCGAIN 400kΩCIRCUITS q q q t w w w e e e r r y y t t t t r r q q u Supply Current 2 IDD2 U.V.L.O. Voltage VUVLO MIN. TYP. MAX. 05S_1XC9201/9202新規 02.09.12 15:16 ページ 540

VIN = 7.5V unless specified*1 : On resistance = 0.4V / measurement current NOTE1 : EFFI = {[(Output Voltage) x (Output Current)] ÷ [(Input Voltage) x (Input Current)]} x 100NOTE2 : The capacity range of the condenser used to set the external CLK frequency is 180 ∼ 300pF Ta=25℃VINmax VOUT VINmin IDD1 ISTB FOSC ΔFOSC ΔVIN･FOSC ΔFOSC ΔTOPR･FOSC MAXDTY MINDTY ILIM IISEN ICEH ICEL VCEH EXT voltage = High VIN=7.5V, CE=VIN=VOUT VIN=20.0V, CE=VIN, VOUT=VSS VIN=7.5V, CE=VOUT=VSS RT=10.0kΩ, CT=220pF VIN=2.5V～20V TOPR=－40～+85℃VIN=7.5V IOUT=300mA VOUT=VSS VOUT=VIN VIN pin voltage - ISEN pin voltage VIN=7.5V, ISEN=7.5V CE=VIN=20.0V, VOUT=0V CE=0V, VIN=20.0V, VOUT=0V Existance of CLK Oscillation, VOUT=0V, CE：Voltage applied Dissapearance of CLK Oscillation, VOUT=0V、CE：Voltage applied VEXT=VIN－0.4V, CE=VOUT=VIN *1 VEXT=0.4V, CE=VIN, VOUT=VSS *1 Connect CSS and RSS, CE : 0V → 7.5V 4.875 －1.0 280 100 4.5 －0.1 －0.1 0.6 5.000 －－1.400115 1300.5330±5 ±5150 005.125 －2.200 2.0 220 235 2.0 380 220 0.1 0.1 V V V V μA μA μA kHz mV μA μA μA V VCEL 0.2 V REXTH 2129 ΩREXTL ΩEFFI 93% TSS 1020 ms RCCGAIN 400kΩq q q t w w w e e e r r y y t t t t r r q q u IDD2 VUVLO MIN. TYP. MAX. PARAMETER Minimum OperatingVoltage Maximum OperatingVoltage Supply Current 1 Stand-by Current Minimum Duty Cycle Output Voltage CLK Oscillation Frequency Frequency Input Stability Current LimiterVoltage ISEN Current CE "High" Voltage CE "Low" Voltage CE "High" Voltage CE "Low" Voltage EXT "High" ON Resistance EXT "Low" ON Resistance CC/GAIN Pin Output Impedance Efficiency (NOTE1) Soft-start Time Supply Current 2 U.V.L.O. Voltage SYMBOL CONDITIONS UNITS CIRCUITS Frequency Temperature Fluctuation Maximum Duty Cycle 05S_1XC9201/9202新規 02.09.12 15:16 ページ 541

VIN = 4.0V unless specifiedExternal components : RFB1 = 200kΩ, RFB2 = 100kΩ, CFB = 82pF*1 : On resistance = 0.4V / measurement current NOTE1 : EFFI = {[(Output Voltage) x (Output Current)] ÷ [(Input Voltage) x (Input Current)]} x 100NOTE2 : The capacity range of the condenser used to set the external CLK frequency is 180 ∼ 300pF Ta=25℃UNITS VINmax VFB VINmin IDD1 ISTB FOSC ΔFOSC ΔVIN･FOSC ΔFOSC ΔTOPR･FOSC MAXDTY MINDTY ILIM IISEN ICEH ICEL VCEH EXT voltage = High VIN=4.0V, CE=VIN=FB VIN=20.0V, CE=VIN, FB=VSS VIN=4.0V, CE=FB=VSS RT=10.0kΩ, CT=220pF VIN=2.5V～20V TOPR=－40～+85℃VIN=4.0V IOUT=300mA FB=VSS FB=VIN VIN pin voltage - ISEN pin voltage VIN=4.0V, ISEN=4.0V CE=VIN=20.0V, FB=0V CE=0V, VIN=20.0V, FB=0V Existance of CLK Oscillation, FB=0V, CE：Voltage applied Dissapearance of CLK Oscillation, FB=0V、CE：Voltage applied EXT=VIN－0.4V, CE=FB=VIN *1 EXT=0.4V, CE=VIN, FB=VSS *1 Connect CSS and RSS, CE : 0V → 4.0V 0.8775 1.0 280 100 4.5 －0.1 －0.1 0.6 0.900 1.400115 1300.5330±5 ±5150 000.9225 2.200 2.0 220 235 2.0 380 220 0.1 0.1 V V V V μA μA μA kHz mV μA μA μA V VCEL 0.2 V REXTH 2740 ΩREXTL 2434 ΩEFFI 93% TSS 1020 ms RCCGAIN 400kΩCIRCUITS q q q t w w w e e e r r y y t t t t r r q q u IDD2 VUVLO MIN. TYP. MAX. PARAMETER SYMBOL CONDITIONS Maximum OperatingVoltage Minimum OperatingVoltage Supply Current 1 Stand-by Current Frequency Temperature Fluctuation Maximum Duty Cycle Minimum Duty Cycle FB Voltage CLK Oscillation Frequency Frequency Input Stability Current LimiterVoltage ISEN Current CE "High" Current CE "Low" Current CE "High" Voltage CE "Low" Voltage EXT "High" ON Resistance EXT "Low" ON Resistance CC/GAIN Pin Output Impedance Efficiency (NOTE1) Soft-start Time Supply Current 2 U.V.L.O. Voltage 05S_1XC9201/9202新規 02.09.12 15:16 ページ 542

3.3V～1.5A 47μF(OS) or10μF(ceramic)×4 VSS VOUT CC/GAIN ～30kΩ220pF 470pF CLK 22μH EXT Isen VIN CE/SS 1μF SD 7.2V 50mΩPMOS 240kΩμF 0.22μF ■Typical Application Circuits XC9201C33AKR 5.0V～1.5A 47μF(OS)+220μF(any) VSS VOUT CC/GAIN ～30kΩ220pF 470pF CLK 22μH EXT Isen VIN CE/SS 1μF SD 12.0V 20mΩPMOS 240kΩ0.33μF 47μF+220μF PMOS : XP132A11A1SR(TOREX) Coil : 22µH(CR105 SUMIDA) Resistor : 50mΩfor Isen (NPR1 KOWA), 30kΩ(trimmer) for CLK, 240kΩfor SS Capacitors : 220pF( ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.22µF(any) for SS,1µF(ceramic) for Bypass 47µF(OS) or 10µF(ceramic) x 4 for CL, 47µF(tantalum) for CIN SD : U3FWJ44N(TOSHIBA) XC9201C50AKR PMOS : XP132A11A1SR(TOREX) Coil : 22µH(CDRH127 SUMIDA) Resistor : 20mΩfor Isen (NPR1 KOWA), 30kΩ(trimmer) for CLK, 240kΩfor SS Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.33µF(any) for SS, 1µF(ceramic) for Bypass 47µF(OS)+220µF(any) for CL, 47µF(tantalum)+220µF(any) for CIN SD : U3FWJ44N(TOSHIBA) 05S_1XC9201/9202新規 02.09.12 15:16 ページ 543

2.5V～3A 47uF(OS)+220μF(any) VSS VOUT CC/GAIN ～30kΩ220kΩ220pF 39pF 470pF CLK 22μH EXT Isen VIN CE/SS 1μF SD 7.2V 20mΩPMOS 240kΩ390kΩ0.22μF 47μF+220μF 12V～1.5A 47μF(OS)+220μF VSS FB CC/GAIN ～30kΩ22kΩ220pF 56pF 470pF CLK 47μH EXT Isen VIN CE/SS XC9201D09AKR 1μF SD 20V 50mΩPMOS 240kΩ270kΩ0.47μF 47μF XC9201D09AKR PMOS : XP132A11A1SR(TOREX) Coil : 22µH(CDRH127 SUMIDA) Resistors : 20mΩfor Isen (NPR1 KOWA), 30kΩ(trimmer) for CLK, 240kΩfor SS, 390kΩfor Output Voltage 100kΩ(trimmer) for Output Voltage Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.22µF(any) for SS, 1µF(ceramic) for Bypass 39pF(ceramic) for FB,47µF(OS) for CL,47µF (tantalum)+220µF(any) for CIN SD : U3FWJ44N(TOSHIBA) PMOS : XP132A11A1SR(TOREX) Coil : 47µH(CR105 SUMIDA) Resistor : 50mΩfor Isen (NPR1 KOWA), 30kΩ(trimmer) for CLK, 240kΩfor SS, 270kΩfor Output Voltage 22kΩ(trimmer) for Output Voltage Capacitors : 220pF(ceramic) for CLK, 470pF(ceramic) for CC/GAIN, 0.47µF(any) for SS, 1µF(ceramic) for Bypass 100pF(ceramic) for FB, 47µF(OS) +220µF(any) for CL, 47µF(tantalum)+220µF(any) for CIN SD : U3FWJ44N(TOSHIBA) 05S_1XC9201/9202新規 02.09.12 15:16 ページ 544

D CLK Q /RESET PWM/PFM switching signal CLK sync signal Output signal to EXT pin Limiter signal PWM/PFM switchinig signal ■Operation Description 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). <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. <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. 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 turn on until the internal circuitry becomes stable. 05S_1XC9201/9202新規 02.09.12 15:16 ページ 545

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) Set the soft start time to a value sufficiently longer than the period of a clock pulse. > Circuit example 1: N-ch open drain > Circuit example 2: CMOS logic (low current dissipation) > Circuit example 3: CMOS logic (low current dissipation), quick off XC9201Series 546 CE/SS pin 〔Inside the IC〕Css Rss ON/OFF signal Vcont CE/SS pin 〔Inside the IC〕Css Rss ON/OFF signal Vcont CE/SS pin 〔Inside the IC〕Css Rss ON/OFF signal Vcont CE/SS pin 〔Inside the IC〕Vcont Css CE,UVLO Vref circuit To Verr amplifier Rss 05S_1XC9201/9202新規 02.09.12 15:16 ページ 546

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 kΩ, f = 1/(-220e-12 x 10e3 x ln(0.26)) = 337.43 kHz. 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. 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 mΩ, ILpeak_limit = 0.15 / 0.1 = 1.5 A 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. XC9201 Series 547 CLK pin 〔Inside the IC〕Rclk CLK Generater Cclk 〔Inside the IC〕Rsen VIN pin Isen pin Limiter signal Comparator with150-mV offset 〔Inside the IC〕Verr CC/GAIN pin RGAIN CC VOUT/FB Vref RVerr 05S_1XC9201/9202新規 02.09.12 15:16 ページ 547

■Directions for use GApplication 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 input- output 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 500Ωto 1kΩ according to the load and hFE of the transistor. Use a ceramic capacitor for Cb, complying with Cb < 1/ ( 2 x π x Rb x Fosc x 0.7), as a rule. 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. 〔Inside the IC〕FB pin Rfb1 Rfb2 Verr amplifier 0.9V Cfb Output voltage Verr 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 Ωor 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 π x Rfb1 x fzfb) Example: When Rfb1 = 455 kΩand Rfb2 = 100 kΩ: VOUT = 0.9 x (455 k + 100 k)/100 k = 4.995 V : Cfb = 1/(2 x π x 455 k x 10 k) = 34.98 pF. 〔Inside the IC〕VIN EXT pin Rb Cb 05S_1XC9201/9202新規 02.09.12 15:16 ページ 548

C_GAIN R_CLK CDD L P-MOS RSEN SD VIN CIN C_SS R_SS Through Hole5 R_CLK,C_CLK,C_GAIN,RFB2 GND C_CLK GRecommended 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 XC9201 Series 549 05S_1XC9201/9202新規 02.09.12 15:16 ページ 549

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. GExternal Components RSENSE Resistor A low value resistor is defined as a resistor with a 10Ωvalue or lower. For RSENSE, the XC9201 series uses a resistor with a value of either 50mΩor 100mΩ. 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 50mΩor 100mΩwill 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 = 100mΩ, I = 1A I = 1A RSENSE = 100mΩ(0.1Ω) Power supply W = 1 x 1 x 0.1 = 0.1 [W] 0.5W, 100mΩresistor should be used XC9201Series 550 Power GND IC GND VDD Line RFB1 CL RFB2 CFB CDD L P-MOS SD VIN CIN C_SS R_SS RSEN C_GAIN C_CLK R_CLK 1 layer Evaluation Board 05S_1XC9201/9202新規 02.09.12 15:16 ページ 550

■Test Circuits ・Fig. 1 (VOUT Type) 22μH 100mΩPMOS SD R_SS C_SS 47μH CLK 5 10KΩ220pF 470pF 1μF 47μF 20μF RL V XC9201C25A R_SS：188kΩ C_SS：0.1μFXC9201C33A R_SS：270kΩ C_SS：0.1μFXC9201C50A R_SS：430kΩ C_SS：0.1μF A 10KΩ220pF CLK 5 0.1μF VOUT/FB 7 CLK 5 A H 10KΩ220pF 0.1μF L 10KΩ0.1μF V A 220pF 0.1μF 1MΩV CLK 5 20KΩ165pF 470pF 22μF RL 100mΩ1μF 240kΩ0.047μF 47μF CFB RFB1 RFB2 10KΩ220pF 0.1μF OSC 10KΩ220pF 0.1μF A V V V ・Fig. 2 ・Fig. 4 ・Fig. 3 ・Fig. 1 (FB Type) ・Fig. 5 ・Fig. 6 ・Fig. 7 05S_1XC9201/9202新規 02.09.12 15:16 ページ 551

■Typical Performance Characteristics XC9201D09AKR (1) OUTPUT VOLTAGE vs. OUTPUT CURRENT VOUT 1.5V, FOSC : 330kHz 1.3 1.4 1.5 1.6 1.7 0.1 100 1000 10000 3.1 3.2 3.3 3.4 3.5 0.1 100 1000 10000 11.8 11.9 12.0 12.1 12.2 0.1 100 1000 10000 4.8 4.9 5.0 5.1 5.2 0.1 100 1000 10000 L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR VOUT 3.3V, FOSC : 330kHz L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR VOUT 5.0V, FOSC : 330kHz L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR VOUT 12.0V, FOSC : 100kHz L=68µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=10µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP132A11C0PR VIN=4.0V 6.0V 8.0V 10.0V 12.0V VIN=3.3V 5.0V 7.2V VIN=18.0V VIN=8.0V 10.0V 12.0V 15.0V Output Current : IOUT (mA) Output Current : IOUT (mA) Output Current : IOUT (mA) Output Current : IOUT (mA) Output Voltage : VOUT (V) Output Voltage : VOUT (V) Output Voltage : VOUT (V) Output Voltage : VOUT (V) 05S_1XC9201/9202新規 02.09.12 15:16 ページ 552

(2) EFFICIENCY vs. OUTPUT CURRENT L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=68µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=10µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP132A11C0PR VOUT 1.5V, FOSC : 330kHz VOUT 3.3V, FOSC : 330kHz VOUT 5.0V, FOSC : 330kHz VOUT 12.0V, FOSC : 100kHz 100 0.1 100 1000 10000 Output Current : IOUT (mA) Efficiency : EFFI (%) VIN=18.0V 100 0.1 100 1000 10000 Output Current : IOUT (mA) Efficiency : EFFI (%) VIN=8.0V 12.0V 10.0 15.0V 100 0.1 100 1000 10000 Output Current : IOUT (mA) Efficiency : EFFI (%) VIN=4.0V 10.0V 8.0V 6.0V 12.0V 100 0.1 100 1000 10000 Output Current : IOUT (mA) Efficiency : EFFI (%) VIN=3.3V 5.0V 7.2V 05S_1XC9201/9202新規 02.09.12 15:16 ページ 553

(3) RIPPLE VOLTAGE vs. OUTPUT CURRENT L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), CD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=22µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=68µH, CL=40µF (Ceramic), CIN=30µF (Ceramic)RSEN=50mΩ, CDD=10µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP132A11C0PR VOUT 1.5V, FOSC : 330kHz VOUT 3.3V, FOSC : 330kHz VOUT 5.0V, FOSC : 330kHz VOUT 12.0V, FOSC : 100kHz L=22µH, CL=47µF (Tantalum), CIN=47µF (Tantalum)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR L=22µH, CL=47µF (Tantalum), CIN=47µF (Tantalum)RSEN=50mΩ, CDD=1µF (Ceramic), SD:U3FWJ44NCGAIN=470pF (Ceramic), Tr:XP162A11C0PR VOUT 1.5V, FOSC : 330kHz VOUT 3.3V, FOSC : 330kHz 100 0.1 100 1000 10000 Output Current : IOUT (mA) 100 0.1 100 1000 10000 Output Current : IOUT (mA) 100 0.1 100 1000 10000 Output Current : IOUT (mA) 100 0.1 100 1000 10000 Output Current : IOUT (mA) 100 0.1 100 1000 10000 Output Current : IOUT (mA) 100 0.1 100 1000 10000 Output Current : IOUT (mA) Ripple Voltage : Vr (mVp-p) Ripple Voltage : Vr (mVp-p) Ripple Voltage : Vr (mVp-p) Ripple Voltage : Vr (mVp-p) Ripple Voltage : Vr (mVp-p) Ripple Voltage : Vr (mVp-p) VIN=4.0V 6.0V 8.0V 10.0V 12.0V VIN=3.3V 5.0V 7.2V VIN=18.0V VIN=8.0V 15.0V 10.0V 12.0V 6.0V 8.0V 10.0V 12.0V VIN=4.0V VIN=3.3V 7.2V 5.0V *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. 05S_1XC9201/9202新規 02.09.12 15:16 ページ 554

Product Information

XC9201DC0AKL specifications and overview.

Summary

PWM Controlled Step-Down DC/DC Converters

Description

PWM Controlled Step-Down DC/DC Converters

Source title XC9201DC0AKL Datasheet(PDF) - Torex Semiconductor

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