XC9206/XC9207/XC9208 Series ETR0503_002 PWM, PWM / PFM Switchable Step-Down DC / DC Converters With Driver Transistor Built-In ☆GO-Compatible ■GENERAL DESCRIPTION The XC9206/XC9207/XC9208 series is a group of DC/DC converters with a built-in 0.4Ω P-channel driver transistor, offered in a SOT-25 package. The ICs are designed to provide high efficiencies and a stable power supply with an output current of 500mA using only a coil, a diode and two ceramic capacitors connected externally. Minimum operating voltage of the XC9206/9207 is 1.8V and 2.0V for XC9208. Output voltage is internally programmable in a range from 0.9V to 4.0V in 100mV increments (accuracy: ±2.0%). Oscillation frequency is selectable from 300kHz, 600kHz and 1.2MHz so that the frequency best suited to your particular application can be selected. Each series features different operation modes: PWM control (XC9206 series), automatic PWM/PFM switching control (XC9207 series) and manual PWM/PFM switching control (XC9208 series). The series gives fast transient response, low ripple and high efficiency over the full range of load (from light load to high output current conditions). The soft start and current control functions are internally optimized. During stand-by, all circuits are shutdown to reduce current consumption to as low as 1.0μA or less. With the built-in U.V.L.O. (Under Voltage Lock Out) function, the internal P-channel driver transistor is forced OFF when input voltage becomes 1.4V or lower. ■APPLICATIONS ■FEATURES ●Mobile phones P-ch driver Tr. Built-in : ON resistance 0.4Ω Output Voltage Range : 0.9V ~ 4.0V (100mV increments) Fixed output voltage accuracy ±2% (PDC, GSM, CDMA, IMT2000 etc.) ●PDAs, Portable communication modems ●Portable games Oscillation Frequency : 300kHz, 600kHz, 1.2MHz Fixed oscillation frequency Accuracy ±15% Stand-by function : Istb = 1μA (MAX.) Current Limiter built-in : 600mA Input Voltage Range : 1.8V ~ 6.0V(XC9206/XC9207) 2.0V ~ 6.0V (XC9208) Output Current : 500mA Maximum Duty Ratio : 100% PWM/PFM Switching Control (XC9207 / XC9208) Ceramic Capacitor Compatible Soft start circuit built-in Small Package : SOT-25 ●Cameras, digital cameras ●Cordless phones ●Note book computers ■TYPICAL APPLICATION CIRCUIT ■ TYPICAL PERFORMANCE CHARACTERISTICS ●Efficiency vs. Output Current XC9208A18C VOUT=1.8V (Oscillation Frequency 1.2MHz) VOUT 4 CE/ MODE VSS CIN:4.7μ F,CL:10μ F, L:4.7μ H(CDRH3D16), 3 SD:CRS02, Topr=25℃ 2 L VIN 5 CIN (ceramic) L SD CL CIN VIN Lx VOUT (500mA) 1 SD :4.7μF (CDRH 3D16,SUMIDA) :CRS02 (SCHOTTKY DIODE,TOSHIBA) :10μF (ceramic) :4.7μF (ceramic) CL (ceramic) Efficiency EFFI (%) CE/MODE 100 90 80 70 60 50 40 30 20 10 0 PWM/PFM Switching Control VIN=2.4V 3.6V 4.2V PWM Control 0.1 1 10 100 1000 Output Current IOUT (mA) 1/16 XC9206/XC9207/XC9208 Series ■PIN ASSIGNMENT ■PIN CONFIGURATION VIN PIN NUMBER PIN NAME CE/MODE Lx VSS VOUT FUNCTION 1 LX Switching Output 2 VSS Ground 3 VOUT Output Voltage Sense 4 CE/MODE Chip Enable/Mode Switch 5 VIN Power Input SOT-25 (TOP VIEW) ■ PRODUCT CLASSIFICATION ●Ordering Information XC9206①②③④⑤⑥: PWM Control XC9207①②③④⑤⑥: PWM / PFM Automatic Switching Control XC9208①②③④⑤⑥: PWM Control, PWM / PFM Automatic Switching Control Manually Selectable DESIGNATOR DESCRIPTION SYMBOL DESCRIPTION ① Type of DC/DC Converter A : 600mA current limiter, Transistor built-in, output voltage internally set (VOUT product), soft start internally set. 09~40 ②③ Output Voltage 09~40 & L ④ Oscillation Frequency ⑤ Package ⑥ Device Orientation : 100mV increments e.g. VOUT=1.5V→②=1, ③=5 : 1.85V VOUT →②=1, ③=L 2.85V VOUT →②=2, ③=L 3 : 300kHz 6 : 600kHz C : 1.2MHz M : SOT-25 (SOT-23-5) R : Embossed tape, standard feed L : Embossed tape, reverse feed * Output voltage 0.9V ~ 4.0V (100mV increments), 1.85V and 2.85V are standard products. Output voltage other than these are available as semi-custom products. 2/16 XC9206/XC9207/XC9208 Series ■ BLOCK DIAGRAM Note: The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "L" level inside, and XC9206 series chooses PWM control. The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "H" level inside, and XC9207 series chooses only PWM/PFM automatic switching control. ■ ABSOLUTE MAXIMUM RATINGS Ta=25℃ PARAMETER SYMBOL RATINGS UNITS VIN Pin Voltage VIN - 0.3 ~ + 6.5 V VSS Pin Voltage VSS - 0.3 ~ + 6.5 V Lx Pin Voltage VLx - 0.3 ~ VIN + 0.3 V VOUT Pin Voltage VOUT - 0.3 ~ + 6.5 V CE / MODE Pin Voltage VCE - 0.3 ~ VIN + 0.3 V Lx Pin Current ILx ± 1000 mA Power Dissipation Pd 250 mW Operating Temperature Range Topr - 40 ~ + 85 ℃ Storage Temperature Range Tstg - 55 ~ + 125 ℃ 3/16 XC9206/XC9207/XC9208 Series ■ ELECTRICAL CHARACTERISTICS XC9206A18CMR, XC9207A18CMR, XC9208A18CMR PARAMETER SYMBOL VOUT=1.8V, FOSC=1.2MHz, Ta=25℃ CONDITIONS MIN. TYP. MAX. UNIT When connected to ext. components 1.764 1.800 1.836 CE=VIN, IOUT=30mA (XC9206, 9207) 1.8 6.0 Output Voltage VOUT Operating Voltage Range VIN Maximum Output Current IOUTMAX U.V.L.O. Voltage VUVLO Supply Current 1 IDD1 CE=VIN, VOUT=0V, Voltage which Lx pin voltage holding "L" level (*1) CE=VIN, VOUT=fixed voltage x 0.9V Supply Current 2 IDD2 CE=VIN, VOUT=fixed voltage x 1.1V Stand-by Current ISTB Oscillation Frequency FOSC PFM Pulse Width Rate PFMDTY CE=VSS, VOUT=fixed voltage x 1.1V When connected to ext. components CE=VIN, IOUT=30mA When connected to ext. components (XC9207, XC9208 only), CE=VIN, IOUT=1mA Maximum Duty Cycle MAXDTY CE=VIN, VOUT=0V 100 - Minimum Duty Cycle MINDTY CE=VOUT=VIN - - Efficiency (*2) EFFI When connected to ext. components, CE=VIN, IOUT=100mA - 86 Lx SW ON Resistance RLx CE=VIN, VOUT=0V, ILx=400mA (*3) - 0.4 Current Limit ILIM VIN=CE=5.0V, VOUT=0V (XC9206, 9207) CE "H" Voltage VCEH (XC9208) (XC9208) When connected to ext. components VOUT=0V, When CE voltage is applied Lx determine "H" VOUT=0V, When CE voltage is applied Lx determine "L" CIRCUIT V ① V ① 2.0 - 6.0 500 - - mA ① 1.00 1.40 1.78 V ② - 255 413 μA ③ - 98 158 μA ③ - 0 1 μA ③ 1.020 1.200 1.380 MHz ① 24 30 ① 36 % % ② 0 % ② % ① 0.9 Ω ④ 600 - mA ④ 1.2 - VIN V ⑤ 0.9 - VIN VSS - 0.3 V ⑤ CE "L" Voltage VCEL PWM "H" Voltage VPWMH When connected to ext. components (XC9208 only), IOUT=1mA (*4) VIN-0.3 - - V ① PWM "L" Voltage VPWML When connected to ext. components (XC9208 only), IOUT=1mA (*4) - - VIN-1.0 V ① CE "H" Current ICEH CE=VIN=5.5V, VOUT=0V -0.1 - 0.1 μA ⑤ CE "L" Current ICEL -0.1 - 0.1 μA ⑤ Soft-Start Time TSS CE=0V, VIN=5.5V, VOUT=0V When connected to ext. components CE=0V → VIN, IOUT=1mA 0.8 - 6.0 ms ① Latch Time Tlat - - 12.0 ms ⑥ When connected to ext. components VIN=CE=5.0V, short VOUT by 1Ω (*5) resistance Test condition: Unless otherwise stated, VIN = 3.6V NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = [ (output voltage x output current) / (input voltage x input current) ] x 100 *3: On resistance = VLx (measurement voltage) / 0.4 *4: The CE/MODE pin of the XC9208A series works also as an external PWM control and PWM/PFM control switching pin. When the IC is in the operation, control is switched to the PWM mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3 V, and to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0 V and equal to or greater than VCEH. *5: Time until it short-circuits VOUT with GND through 1Ωof resistance from a state of operation and is set to VOUT=0V from current limit pulse generating. 4/16 XC9206/XC9207/XC9208 Series ■ ELECTRICAL CHARACTERISTICS (Continued) XC9206A25CMR, XC9207A25CMR, XC9208A25CMR VOUT=2.5V, FOSC=1.2MHz, Ta=25℃ PARAMETER SYMBOL CONDITIONS MIN. Output Voltage VOUT Operating Voltage Range VIN Maximum Output Current IOUTMAX U.V.L.O. Voltage VUVLO Supply Current 1 IDD1 CE=VIN, VOUT=0V, Voltage which Lx pin voltage holding "L" level (*1) CE=VIN, VOUT=fixed voltage x 0.9V TYP. MAX. UNIT When connected to ext. components 2.450 2.500 2.550 CE=VIN, IOUT=30mA (XC9206, 9207) 1.8 6.0 (XC9208) When connected to ext. components CIRCUIT V ① V ① 2.0 - 6.0 500 - - mA ① 1.00 1.40 1.78 V ② - 255 413 μA ③ Supply Current 2 IDD2 CE=VIN, VOUT=fixed voltage x 1.1V - 98 158 μA ③ Stand-by Current ISTB - 0 1 μA ③ Oscillation Frequency FOSC CE=VSS, VOUT=fixed voltage x 1.1V When connected to ext. components CE=VIN, IOUT=30mA MHz ① PFM Pulse Width Rate PFMDTY When connected to ext. components (XC9207, XC9208 only), CE=VIN, IOUT=1mA 24 30 % ① Maximum Duty Cycle MAXDTY CE=VIN, VOUT=0V 100 - % ② Minimum Duty Cycle MINDTY CE=VOUT=VIN When connected to ext. components, CE=VIN, IOUT=100mA CE=VIN, VOUT=0V, ILx=400mA (*3) - - % ② - 91 % ① Efficiency (*2) EFFI Lx SW ON Resistance RLx Current Limit ILIM CE "H" Voltage VCEH CE "L" Voltage VCEL PWM "H" Voltage VPWMH PWM "L" Voltage VPWML CE "H" Current ICEH CE "L" Current ICEL Soft-Start Time TSS Latch Time Tlat VIN=CE=5.0V, VOUT=0V VOUT=0V, When CE (XC9206, 9207) voltage is applied Lx (XC9208) determine "H" VOUT=0V, When CE voltage is applied Lx determine "L" When connected to ext. components (XC9208 only), IOUT=1mA (*4) When connected to ext. components (*4) (XC9208 only), IOUT=1mA CE=VIN=5.5V, VOUT=0V CE=0V, VIN=5.5V, VOUT=0V When connected to ext. components CE=0V →VIN, IOUT=1mA When connected to ext. components VIN=CE=5.0V, short VOUT by 1Ω resistance (*5) 1.020 1.200 1.380 36 0 - 0.4 0.9 Ω ④ - 600 - mA ④ 1.2 - VIN 0.9 - VIN V ⑤ VSS - 0.3 V ⑤ VIN-0.3 - - V ① - - VIN-1.0 V ① -0.1 - 0.1 μA ⑤ -0.1 - 0.1 μA ⑤ 0.8 - 6.0 ms ① - - 12.0 ms ⑥ Test condition : Unless otherwise stated, VIN = 3.6V NOTE: *1 : Including hysteresis operating voltage range. *2 : EFFI = [ (output voltage x output current) / (input voltage x input current) ] x 100 *3 : On resistance = VLX (measurement voltage) / 0.4 *4 : The CE/MODE pin of the XC9208A series works also as an external PWM control and PWM/PFM control switching pin. When the IC is in the operation, control is switched to the PWM mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3 V, and to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0 V and equal to or greater than VCEH. *5 : Time until it short-circuits VOUT with GND through 1Ω of resistance from a state of operation and is set to VOUT=0V from current limit pulse generating. 5/16 XC9206/XC9207/XC9208 Series ■ ELECTRICAL CHARACTERISTICS (Continued) XC9206A33CMR, XC9207A33CMR, XC9208A33CMR PARAMETER SYMBOL Output Voltage VOUT Operating Voltage Range VIN Maximum Output Current IOUTMAX U.V.L.O. Voltage VUVLO Supply Current 1 VOUT=3.3V,FOSC=1.2MHz, Ta=25℃ MIN. TYP. MAX. UNIT CIRCUIT CONDITIONS When connected to ext. components 3.234 3.300 3.366 CE=VIN, IOUT=30mA (XC9206, 9207) 1.8 6.0 (XC9208) V ① V ① 2.0 - 6.0 500 - - mA ① CE=VIN, VOUT=0V, Voltage which Lx pin voltage holding "L" 1.00 level (*1) 1.40 1.78 V ② IDD1 CE=VIN, VOUT=fixed voltage x 0.9V - 370 585 μA ③ When connected to ext. components Supply Current 2 IDD2 CE=VIN, VOUT=fixed voltage x 1.1V - 120 180 μA ③ Stand-by Current Istb - 0 1 μA ③ Oscillation Frequency FOSC MHz ① PFM Pulse Width Rate PFMDTY CE=VSS, VOUT=fixed voltage x 1.1V When connected to ext. components CE=VIN, IOUT=30mA When connected to ext. components (XC9207, XC9208 only), CE=VIN, IOUT=1mA % ① Maximum Duty Cycle MAXDTY CE=VIN, VOUT=0V % ② Minimum Duty Cycle MINDTY CE=VOUT=VIN When connected to ext. components, CE=VIN, IOUT=100mA CE=VIN, VOUT=0V, ILx=400mA (*3) % ② % ① Efficiency (*2) EFFI Lx SW ON Resistance RLx Current Limit ILIM CE "H" Voltage VCEH CE "L" Voltage VCEL PWM "H" Voltage VPWMH PWM "L" Voltage VPWML CE "H" Current ICEH CE "L" Current ICEL Soft Start Time TSS Latch Time Tlat VIN=CE=5.0V, VOUT=0V VOUT=0V, When CE (XC9206, 9207) voltage is applied Lx (XC9208) determine "H" VOUT=0V, When CE voltage is applied Lx determine "L" When connected to ext. components (*4) (XC9208 only), IOUT=1mA When connected to ext. components (XC9208 only), IOUT=1mA (*4) CE=VIN=5.5V, VOUT=0V CE=0V, VIN=5.5V, VOUT=0V When connected to ext. components CE=0V → VIN, IOUT=1mA When connected to ext. components VIN=CE=5.0V, short VOUT by 1Ω resistance (*5) 1.020 1.200 1.380 26 32 100 - - - - 92 38 0 - 0.4 0.9 Ω ④ - 600 - mA ④ 1.2 - VIN 0.9 - VIN V ⑤ VSS - 0.3 V ⑤ VIN-0.3 - - V ① - - VIN-1.0 V ① -0.1 - 0.1 μA ⑤ -0.1 - 0.1 μA ⑤ 0.8 - 6.0 ms ① - - 12.0 ms ⑥ Test condition: Unless otherwise stated, VIN = 5.0V NOTE: *1: Including hysteresis operating voltage range. *2: EFFI = [ (output voltage x output current) / (input voltage x input current) ] x 100 *3: On resistance = VLX (measurement voltage) / 0.4 *4: The CE/MODE pin of the XC9208A series works also as an external PWM control and PWM/PFM control switching pin. When the IC is in the operation, control is switched to the PWM mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3 V, and to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0 V and equal to or greater than VCEH. *5: Time until it short-circuits VOUT with GND through 1Ω of resistance from a state of operation and is set to VOUT=0V from current limit pulse generating. 6/16 XC9206/XC9207/XC9208 Series ■ TYPICAL APPLICATION CIRCUIT CE/MODE VOUT 4 CE/ MODE VSS 3 2 L VIN 5 VIN Lx VOUT (500mA) 1 CIN (ceramic) SD CL (ceramic) * XC9206/9207/9208 series wire connection ●FOSC=1.2MHz L : 4.7μH (CDRH3D16, SUMIDA) SD : CRS02 (TOSHIBA) CIN : 4.7μF (Ceramic) CL : 10μF (Ceramic) ●FOSC=600kHz L : 10μH (CDRH4D18C, SUMIDA) SD : CRS02 (TOSHIBA) CIN : 4.7μF (Ceramic) CL : 10μF (Ceramic) ●FOSC=300kHz L : 22μH (CDRH4D18, SUMIDA) SD : CRS02 (TOSHIBA) CIN : 4.7μF (Ceramic) CL : 10μF (Ceramic) *SD : Schottky diode ■OPERATIONAL EXPLANATION Each unit of the XC9206/9207/9208 series consists of a reference voltage source, ramp wave circuit, error amplifier, PWM comparator, phase compensation circuit, output voltage adjustment resistors, driver transistor, current limiter circuit, U.V.L.O. circuit and others. The series ICs compare, using the error amplifier, the voltage of the internal voltage reference source with the feedback voltage from the VOUT pin through resistors R1 and R2. Phase compensation is performed on the resulting error amplifier output, to input a signal to the PWM comparator to determine the turn-on time during PWM operation. The PWM comparator compares, in terms of voltage level, the signal from the error amplifier with the ramp wave from the ramp wave circuit, and delivers the resulting output to the buffer driver circuit to cause the Lx pin to output a switching duty cycle. This process is continuously performed to ensure stable output voltage. The current feedback circuit monitors the P-channel MOS driver transistor current for each switching operation, and modulates the error amplifier output signal to provide multiple feedback signals. This enables a stable feedback loop even when a low ESR capacitor, such as a ceramic capacitor, is used, ensuring stable output voltage. < Reference Voltage Source > The reference voltage source provides the reference voltage to ensure stable output voltage of the ICs. < Ramp Wave Circuit > The ramp wave circuit determines switching frequency. The frequency is fixed internally and can be selected from 300kHz, 600 kHz and 1.2 MHz. Clock pulses generated in this circuit are used to produce ramp waveforms needed for PWM operation, and to synchronize all the internal circuits. < Error Amplifier > The error amplifier is designed to monitor output voltage. The amplifier compares the reference voltage with the feedback voltage divided by the internal resistors (R1 and R2). When a voltage lower than the reference voltage is fed back, the output voltage of the error amplifier increases. The gain and frequency characteristics of the error amplifier output are fixed internally to deliver an optimized signal to the mixer. <Current Limit> The current limiter circuit of the XC9206/9207/9208 series monitors the current flowing through the P-channel MOS driver transistor connected to the Lx pin, and features a combination of the constant-current type current limit mode and the operation suspension mode. ①When the driver current is greater than a specific level, the constant-current type current limit function operates to turn off the pulses from the Lx pin at any given timing. ②When the driver transistor is turned off, the limiter circuit is then released from the current limit detection state. ③At the next pulse, the driver transistor is turned on. However, the transistor is immediately turned off in the case of an over current state. ④When the over current state is eliminated, the IC resumes its normal operation. The IC waits for the over current state to end by repeating the steps ① through ③ . If an over current state continues for several msec and the above three steps are repeatedly performed, the IC performs the function of latching the OFF state of the driver transistor, and goes into operation suspension mode. Once the IC is in suspension mode, operations can be resumed by either turning the IC off via the CE /MODE pin, or by restoring power to the VIN pin. The suspension mode does not mean a complete shutdown, but a state in which pulse output is suspended; therefore, the internal circuitry remains in operation. The constant-current type current limit of the XC9206A/9207A/9208A series can be set at 600 mA. Limit < #ms Limit< #mS Limit > #ms Limit> #mS Current Limit LEVEL IOUT 0mA VOUT VSS LX CE/MODE Restart VIN 7/16 XC9206/XC9207/XC9208 Series ■OPERATIONAL EXPLANATION (Continued) < U.V.L.O. Circuit> When the VIN pin voltage becomes 1.4 V or lower, the P-channel output driver transistor is forced OFF to prevent false pulse output caused by unstable operation of the internal circuitry. When the VIN pin voltage becomes 1.8 V or higher, switching operation takes place. By releasing the U.V.L.O. function, the IC performs the soft start function to initiate output startup operation. The soft start function operates even when the VIN pin voltage falls momentarily below the U.V.L.O. operating voltage. The U.V.L.O. circuit does not cause a complete shutdown of the IC, but causes pulse output to be suspended; therefore, the internal circuitry remains in operation. < Function of CE/MODE pin > The XC9206/9207/9208 series will enter into shut down state by inputting a low level signal to the CE/MODE pin. During a shut down state, the current consumption of the IC becomes 0μA (TYP.), with a state of high impedance at the Lx pin and VOUT pin. The IC starts its operation by inputting a high level signal to the CE/MODE pin. The input of the CE/MODE pin is a CMOS input and the sink current is 0μA (TYP.). ●XC9206A / 07A series - Examples of how to use CE/MODE pin SW_CE STATUS ON Chip Disable A OFF ON B PWM control (XC9206), PWM/PFM automatic switching control (XC9207) PWM control (XC9206), PWM/PFM automatic switching control (XC9207) OFF (A) Chip Disable (B) ●XC9208A series - Examples of how to use CE/MODE pin A (A) (B) B SW_CE SW_PMW/PFM STATUS ON * Synchronous PWM control OFF ON Non-synchronous PWM/PFM automatic switching control OFF OFF Chip Disable ON * Chip Disable OFF ON Non-synchronous PWM/PFM automatic switching control OFF OFF Synchronous PWM control Intermediate voltage can be generated by RM1 and RM2. Please set the value of each R1, R2, RM1, RM2 at around 100kΩ. For switches, CPU open-drain I/O port and transistor can be used. < PWM / PFM > XC9207/9208 series features PWM/PFM automatic switching control. With the automatic PWM/PFM switching control function, the series ICs are automatically switched from PWM control to PFM control mode under light load conditions. If during light load conditions the coil current becomes discontinuous and on-time rate falls lower than PFM duty, the PFM circuit operates to output a pulse with a fixed on-time rate from the Lx pin. During PFM operation with this fixed on-time rate, pulses are generated at different frequencies according to conditions of the moment. This causes a reduction in the number of switching operations per unit of time, resulting in efficiency improvement under light load conditions. However, since pulse output frequency is not constant, consideration should be given if a noise filter or the like is needed. Necessary conditions for switching to PFM operation depend on input voltage, load current, coil value and other factors. 8/16 XC9206/XC9207/XC9208 Series ■ NOTES ON USE ● Application Information 1. The XC9206/9207/9208 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. If the input-output potential difference is large, connect an electrolytic capacitor in parallel to compensate for insufficient capacitance. 2. Spike noise and ripple voltage arise in a switching regulator as with a DC/DC converter. These are greatly influenced by external component selection, such as the coil inductance, capacitance values, and board layout of external components. Once the design has been completed, verification with actual components should be done. 3. When the difference between VIN and VOUT is large and the load current is light, very narrow pulses will be outputted, and there is the possibility that some cycles may be skipped completely. ●Oscillation Wave Form (FOSC=1.2MHz) ① VIN = 5.5V, VOUT=1.8V, IOUT=10mA CH1 : Lx CH2 : VOUT AC-COUPLED L : 4.7μH SD CIN CL : CRS02 : 4.7μF : 10μF (CDRH3D16, SUMIDA) (TOSHIBA) (Ceramic) (Ceramic) 4. When the difference between VIN and VOUT is small, and the load current is heavy, very wide pulses will be outputted and there is the possibility that some cycles may be skipped completely: in this case, the Lx pin may not go low at all. ●Oscillation Wave Form (FOSC=1.2MHz) ② VIN = 2.0V, VOUT=1.8V, IOUT=60mA CH1 : Lx CH2 : VOUT AC-COUPLED L : 4.7μH SD CIN CL : CRS02 : 4.7μF : 10μF (CDRH3D16, SUMIDA) (TOSHIBA) (Ceramic) (Ceramic) 5. With the IC, the peak current of the coil is controlled by the current limit circuit. Since the peak current increases when dropout voltage or load current is high, current limit starts operating, and this can lead to instability. When peak current becomes high, please adjust the coil inductance value and fully check the circuit operation. In addition, please calculate the peak current according to the following formula: Ipk = (VIN - VOUT) x On Duty / (2 x L x FOSC) + IOUT OnDuty: OnDuty ratio of Pch Driver Transistor L : Coil Inductance Value FOSC : Oscillation Frequency 6. When the peak current which exceeds limit current flows within the specified time, the built-in P-ch driver transistor is turned off. During the time until it detects limit current and before the built-in transistor can be turned off, the current for limit current flows; therefore, care must be taken when selecting the rating for the coil or the schottky diode. 7. When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance. 9/16 XC9206/XC9207/XC9208 Series ■ NOTES ON USE (Continued) ●Application Information (Continued) 8. Care must be taken when laying out the PC Board, in order to prevent misoperation of the current limit mode. Depending on the state of the PC Board, latch time may become longer and latch operation may not work. In order to avoid the effect of noise, the board should be laid out so that capacitors are placed as close to the chip as possible. 9. Use of the IC at voltages below the recommended voltage range may lead to instability. 10. This IC should be used within the stated absolute maximum ratings in order to prevent damage to the device. 11. Depending on the input-output voltage differential, or load current, some pulses may be skipped, and the ripple voltage may increase. When the series' duty cycle is digitally signalized, the linear duty cycle and the digitally signalized duty cycle cannot carry out completely the same change, which means that the duty cycle does not change linearly. The output is stabilized by applying the phase compensation and adjusting the duty cycle, even when the duty cycle loses the linear change in the whole circuit. When the state where the output was stabilized is continued by applying phase compensation to duty cycle which lost linearity, ripple voltage does not increase more than it. The ripple voltage may increase to about several 10mV according to operating conditions. It is possible, by increasing the capacitance values, to reduce the ripple voltage. The operating conditions are greatly influenced by the dropout voltage, the load current, the delay-time, or the external components, such as the coil inductance, and the capacitance values. Verification with actual parts should be done. ●The Increase of Ripple Voltage (1.2MHz) ① VIN=4.2V, VOUT=1.8V, IOUT=180mA ② VIN=4.2V, VOUT=1.8V, IOUT=60mA CH1: Lx CH1: Lx CH2: VOUT CH2: VOUT AC-COUPLED AC-COUPLED ③ VIN=3.6V, VOUT=1.8V, IOUT=30mA CH1: Lx CH2: VOUT AC-COUPLED 10/16 L : 4.7μH SD CIN CL : CRS02 : 4.7μF : 10μF (CDRH3D16, SUMIDA) (TOSHIBA) (Ceramic) (Ceramic) XC9206/XC9207/XC9208 Series ■ NOTES ON USE (Continued) ● Instructions on Pattern Layout 1. In order to stabilize VDD's voltage level, we recommend that a by-pass capacitor (CIN) be connected as close as possible to the VIN & VSS pins. 2. Please mount each external component as close to the IC as possible, and connect it to GND with the shortest possible PCB traces. 3. Wire external components as close to the IC as possible and use thick, short connecting traces to reduce the circuit impedance. 4. Make sure that the PCB GND traces are as thick as possible, as variations in ground potential caused by high ground currents at the time of switching may result in instability. 5. Please connect SD anode directly to the by-pass capacitor CIN (-) in order to minimize SD noise affect on to the VSS pin of the IC. Also, take distance between the VSS pin and the SD anode for having large impedance as possible. We recommend that a ferrite bead mount pattern be arranged for the case that the SD noise can not be reduced by using the pattern layout as shown below. 6. Please do not make the traces under the IC to carry switching main current. It may cause a malfunction of the IC. <BOTTOM VIEW> <TOP VIEW> VOUT L VSS XC9206/07/08 R.1.1 SD SOT-25 CE VIN Ferrite Bead Figure XC9206/07/08Series Pattern Layout 11/16 XC9206/XC9207/XC9208 Series ■TEST CIRCUITS Circuit ① Circuit ② 4 CE VOUT /MODE 3 4 VSS 2 Lx 1 VOUT CE /MODE 3 VSS 2 Lx 1 L 5 VIN V CL CIN VI 5 SD RL 200Ω 1μF Circuit ③ Circuit ④ CE VOUT 3 /MODE 4 A 5 VSS 2 Lx 1 VIN 4 5 VOUT CE /MODE 3 VSS 2 Lx 1 VIN L 1μF V 1μF Circuit ⑤ Circuit ⑥ H 4 A CE VOUT /MODE L 4 3 VSS 2 Lx 1 CE VOUT /MODE 3 VSS 2 Lx 1 L 5 VIN 5 VI SD 1kΩ CIN 1μF 12/16 1.2MHz 600kHz 300kHz CIN 4.7μF (ceramic) 4.7μF (ceramic) 4.7μF (ceramic) CL 10μF (ceramic) 10μF (ceramic) 10μF (ceramic) L 4.7μH 10μH 22μH SD Schottky Diode Schottky Diode Schottky Diode V CL 1Ω XC9206/XC9207/XC9208 Series ■TYPICAL PERFORMANCE CHARACTERISTICS (1) Output Voltage vs. Output Current XC9208A18C VOUT=1.8V (Oscillation Frequency1.2MHz) XC9208A186 VOUT=1.8V (Oscillation Frequency 600kHz) CIN:4.7μ F,CL:10μ F, L:4.7μ H(CDRH3D16), CIN:4.7μ F,CL:10μ F, L:10μ H(CDRH4D18C), SD:CRS02, Topr=25℃ SD:CRS02, Topr=25℃ 2 1.9 PWM/PFM Switching Control Output OUT (V) OutputVoltage: Voltage V VOUT (V) Output OutputVoltage: Voltage V VOUT OUT (V) (V) 2 VIN=2.4V 1.8 PWM Control 3.6V 1.7 4.2V 1.6 1.5 1.9 PWM/PFM Switching Control 3.6V, 4.2V 1.8 PWM Control 1.7 VIN=2.4V 1.6 1.5 0.1 1 10 100 1000 0.1 1 10 100 1000 Output Current:IOUT IOUT(mA) (mA) OutputCurrent: Current IOUT (mA) Output Output Current:IOUT IOUT (mA) Output Current (2) Efficiency vs. Output Current XC9208A183 VOUT=1.8V (Oscillation Frequency 300kHz) CIN:4.7μ F,CL:10μ F, L:22μ H(CDRH4D28C), SD:CRS02, Topr=25℃ 1.9 PWM/PFM Switching Control Efficiency: EFFI (%) Output Voltage Voltage:VOUT VOUT (V) (V) 2 3.6V, 4.2V 1.8 PWM Control 1.7 VIN=2.4V 1.6 1.5 0.1 1 10 100 1000 Output Current: IOUT (mA) Efficiency: EFFI (%) Efficiency: EFFI (%) Output Current:IOUT IOUT (mA) (mA) Output Current Output Current: IOUT (mA) Output Current: IOUT (mA) 13/16 XC9206/XC9207/XC9208 Series ■TYPICAL PERFORMANCE CHARACTERISTICS (Continued) (3) Ripple Voltage vs. Output Current XC9208A186 VOUT=1.8V (Oscillation Frequency 600kHz) XC9208A18C VOUT=1.8V (Oscillation Frequency 1.2MHz) CIN:4.7μ F,CL:10μ F, L:4.7μ H(CDRH3D16), CIN:4.7μ F,CL:10μ F, L:10μ H(CDRH4D18C), SD:CRS02, Topr=25℃ RippleVoltage Voltage:VrVr(mV) (mV) Ripple Ripple Voltage Ripple Voltage:VrVr(mV) (mV) 80 60 PWM Control 4.2V PWM/PFM Switching Control 40 3.6V VIN=2.4V 20 0 1 10 100 1000 OutputCurrent: Current IOUT (mA) Output IOUT (mA) CIN:4.7μ F,CL:10μ F, L:22μ H(CDRH3D28C), SD:CRS02, Topr=25℃ 100 RippleVoltage: Voltage Vr (mV) Ripple 60 PWM Control PWM/PFM Switching Control 40 4.2V 3.6V VIN=2.4V 20 80 60 PWM Control PWM/PFM Switching Control 40 3.6V 4.2V VIN=2.4V 20 0 0.1 1 10 0.1 1 10 100 Output Current:IOUT IOUT (mA) Output Current (mA) XC9208A183 VOUT=1.8V (Oscillation Frequency 300kHz) 100 Output Current: Current IOUT (mA) Output IOUT (mA) ■ PACKAGING INFORMATION 14/16 80 0 0.1 ●SOT-25 SD:CRS02, Topr=25℃ 100 100 1000 1000 XC9206/XC9207/XC9208 Series ■ MARKING RULE ●SOT-25 5 4 ① 1 ② ① Represents product name and type of DC/DC converters MARK PRODUCT SERIES 6 7 8 XC9206AxxxMx XC9207AxxxMx XC9208AxxxMx ③ ④ 2 3 * Character inversion is used. SOT-25 (TOP VIEW) ② Represents integer of output voltage and oscillation frequency MARK OUTPUT VOLTAGE (V) FOSC=300kHz FOSC=600kHz FOSC=1.2MHz XC920xx②x3Mx XC920xx②x6Mx XC920xx②xCMx 0 1 2 0 1 2 A B C 0.x 1.x 2.x 3 4 3 4 D E 3.x 4.x ③ Represents decimal number of output voltage and oscillation frequency MARK FOSC=300kHz FOSC=600kHz FOSC=1.2MHz XC920xxx③3Mx XC920xxx③6Mx XC920xxx③CMx 0 1 2 3 4 5 6 7 8 Z 9 A B C D E F H K L Y M A B C D E F H K L Y M OUTPUT VOLTAGE (V) x. 0 x. 1 x. 2 x. 3 x. 4 x. 5 x. 6 x. 7 x. 8 x. 85 x. 9 * Output voltage 0.9V ~ 4.0V (100mV increments), 1.85V and 2.85V are standard products. Output voltages other than these are available as semi-custom products. ②③ example : OSCILLATION FREQUENCY 300kHz 600kHz 1.2MHz VOUT=3.3V ② ③ 3 3 3 D D D MARK VOUT=5.0V ② ③ 5 0 5 A F A VOUT=1.85V ② ③ 1 Z 1 Y B Y ④ Represents production lot number 0 to 9, A to Z repeated (G, I, J, O, Q, W excepted) 15/16 XC9206/XC9207/XC9208 Series 1. The products and product specifications contained herein are subject to change without notice to improve performance characteristics. Consult us, or our representatives before use, to confirm that the information in this catalog is up to date. 2. We assume no responsibility for any infringement of patents, patent rights, or other rights arising from the use of any information and circuitry in this catalog. 3. Please ensure suitable shipping controls (including fail-safe designs and aging protection) are in force for equipment employing products listed in this catalog. 4. The products in this catalog are not developed, designed, or approved for use with such equipment whose failure of malfunction can be reasonably expected to directly endanger the life of, or cause significant injury to, the user. (e.g. Atomic energy; aerospace; transport; combustion and associated safety equipment thereof.) 5. Please use the products listed in this catalog within the specified ranges. Should you wish to use the products under conditions exceeding the specifications, please consult us or our representatives. 6. We assume no responsibility for damage or loss due to abnormal use. 7. All rights reserved. No part of this catalog may be copied or reproduced without the prior permission of Torex Semiconductor Ltd. 16/16