RP506K Series. 2A *1 PWM/VFM Step-down DC/ DC Converter with Synchronous Rectifier OUTLINE NO.EA

Transcription

1 RP56K Series 2A *1 PWM/VFM Step-down DC/ DC Converter with Synchronous Rectifier OUTLINE NO.EA The RP56K Series are low supply current CMOS-based PWM/VFM step-down DC/ DC converters with synchronous rectifier featuring 2A *1 output current. Internally, a single IC consists of an oscillator, a reference voltage unit, an error amplifier, a switching control circuit, a mode control circuit, a soft start circuit, a latch protection circuit, an under-voltage lockout (UVLO) circuit, a thermal shutdown circuit, and switching transistors. By simply using an inductor and capacitors as external components, without connecting any diode, a low ripple and high efficiency synchronous rectifier step-down DC/ DC converter can be easily configured. RP56K is available in DFN(PLP) package which achieves high-density mounting on boards. RP56K is available in the fixed output voltage type (RP56Kxx1A/ B/ D/ E) which can be set by.1 V step and the output voltage accuracy is as high as ±1.5% or ±18mV, or the adjustable output voltage type (RP56K1C/ F) which can be set by using the external resistors. The oscillator frequency can be selected from 2.25MHz (RP56Kxx1A/ B/ C) or 1.2MHz (RP56K1C/ F). By inputting a signal to MODE pin, RP56K can choose PWM/VFM auto switching control or forced PWM control. In low output current, PWM/VFM auto switching control automatically switches from PWM mode to VFM mode in order to achieve high efficiency. Likewise, in low output current, fixed PWM control switches at fixed frequency in order to reduce noise. RP56K contains a latch type protection circuit which latches the built-in driver to the OFF state during high load or if the output is short-circuited for a specified time (protection delay time). The latch protection circuit can be released by once setting the IC into the standby mode with the CE pin and then setting it back to the active mode, or, by turning the power off and back on. Setting the supply voltage lower than the UVLO detector threshold can also release the latch protection circuit. RP56K also contains a thermal shutdown circuit which detects overheating of the regulator if the output pin (V OUT ) is shorted to the ground pin (GND) etc. and stops regulator operation to protect it from damage. The soft-start time is fixed within the IC (Typ. 15µs), but it is also adjustable by using external capacitors. RP56K includes a power good (PG) function which monitors the V OUT pin voltage or the feedback pin voltage (V FB ), and switches the PG pin to low if any abnormal condition is detected. *1 This is an approximate value. The output current depends on conditions and external components. 1

2 RP56K FEATURES Supply Current Typ. 48µA (VFM mode, Lx at no load) Standby Current Max. 5µA Input Voltage Range 2.5V to 5.5V (Absolute Maximum Ratings: 6.5V) Range.8V to 3.3V *2 (RP56Kxx1A/ B/ C).6V to 3.3V *2 (RP56Kxx1D/ E/ F) Accuracy ±1.5%(VSET *3 1.2V), ±18mV(VSET<1.2V) T (RP56Kxx1A/ B/ D/ E) Feedback Voltage Accuracy ±9mV(VFB=.6V) (RP56K1C/ F) / Feedback Voltage Temperature Coefficient ±1ppm/ ºC Oscillator Frequency Typ. 2.25MHz (RP56Kxx1A/ B/ C) Oscillator Maximum Duty Min. 1% Typ. 1.2MHz (RP56Kxx1D/ E/ F) Built-in Driver ON Resistance Typ. Pch..13Ω, Nch..125Ω (VIN=3.6V) UVLO Detector Threshold Typ. 2.2V Inductor Current Limit Circuit Current limit Typ. 2.8A Latch Type Protection Circuit Typ. 1.5ms Package DFN(PLP) *2 Please refer to Electrical Characteristics for more information. Fixed output voltage type (RP56Kxx1A/ B/ D/ E) can be set by.1 V step. *3 V SET =Set APPLICATION Power source for Li-ion battery-used equipment Power source for portable communication equipment, camcorder, DSC, Notebook PC Power source for HDD, WLAN 2

3 RP56K BLOCK DIAGRAM RP56Kxx1A/D Ramp Compensation Current Feedback PV IN AV IN UVLO Thermal Protection Current Detector L X Soft Start Vref Switching Control T SS ( L during Soft Start) Mode Control OSC PGND V OUT MODE CE AGND Chip Enable Over /Under Voltage Detection OVD UVD PG RP56Kxx1B/E Ramp Compensation Current Feedback PV IN AV IN UVLO Thermal Protection Current Detector L X Soft Start Vref Switching Control T SS ( L during Soft Start) Mode Control OSC PGND V OUT MODE CE AGND Chip Enable Over /Under Voltage Detection OVD UVD PG 3

4 RP56K RP56K1C/F Ramp Compensation Current Feedback PV IN AV IN UVLO Thermal Protection Current Detector L X Soft Start Vref Switching Control T SS ( L during Soft Start) Mode Control OSC PGND V FB MODE CE AGND Chip Enable Over /Under Voltage Detection OVD UVD PG SELECTION GUIDE The set output voltage, the output voltage type, the auto-discharge function *4, and the oscillator frequency for the ICs are user-selectable options. Product Name Package Quantity per Reel Pb Free Halogen Free RP56Kxx1$(y)-TR DFN(PLP) , pcs Yes Yes xx: Designation of the set output voltage (V SET ) For Fixed Type:.6V (6) *5 to 3.3V (33) in.1v steps *6 For Adjustable Type:.6V (1) only (y): If V SET includes the 3rd digit, indicate the digit of.1v. (1.25V) Ex. If V SET is 1.25V, RP56K121$5-TR-FE. $: Designation of version Version Type Auto-discharge Function Oscillator Frequency A Fixed No 2.25MHz B Fixed Yes 2.25MHz C Adjustable No 2.25MHz D Fixed No 1.2MHz E Fixed Yes 1.2MHz F Adjustable No 1.2MHz *4 Auto-discharge function quickly lowers the output voltage to V, when the chip enable signal is switched from the active mode to the standby mode, by releasing the electrical charge accumulated in the external capacitor. *5 V SET can be set only within the specified range of voltage. Please refer to Electrical Characteristics for details. *6.5V step is also available as a custom code. 4

5 RP56K PIN CONFIGURATION Top View Bottom View PIN DESCRIPTION RP56K: DFN(PLP) *7 Pin No. Symbol Description 1 PV IN PV IN Input Voltage Pin *8 2 AV IN AV IN Input Voltage Pin *8 3 PG Power Good Pin 4 CE Chip Enable Pin ( H active) 5 MODE 6 T SS Soft-start Pin Mode Control Pin ( H Forced PWM Control, L PWM/ VFM Auto Switching Control) 7 V OUT / V FB Output/ Feedback Voltage Pin 8 AGND Analog Ground Pin *9 9 L X Switching Pin 1 PGND Power Ground Pin *9 *7 The tab on the bottom of the package enhances thermal performance and is electrically connected to GND (substarate level). It is recommended that the tab be connected to the ground plane on the board. If not, the tab can be left open. *8 No.1 pin and No.2 pin must be wired to the V IN plane when mounting on boards. *9 No.8 pin and No.1 pin must wired to the GND plane when mounting on boards. 5

6 RP56K ABSOLUTE MAXIMUM RATINGS (AGND=PGND=V) Symbol Item Rating Unit V IN AV IN / PV IN Pin Voltage -.3 to 6.5 V V LX L X Pin Voltage -.3 to AV IN / PV IN +.3 V V CE CE Pin Voltage -.3 to 6.5 V V OUT / V FB V OUT / V FB Pin Voltage -.3 to 6.5 V V MODE MODE Pin Voltage -.3 to 6.5 V V PG PG Pin Voltage -.3 to 6.5 V V TSS T SS Pin Voltage -.3 to AV IN +.3 V I LX L X Pin 2.8 A P D Power Dissipation *1 (DFN2527-1) 91 (Standard Land Pattern *1 ) mw 14 (High Wattage Land Pattern *1 ) mw TTa Operating Temperature Range -4 to +85 ºC TTstg Storage Temperature Range -55 to +125 ºC * 1 For more information about Power Dissipation, Standard Land Pattern and High Wattage Land Pattern, please refer to Package Information. ABSOLUTE MAXIMUM RATINGS Electronic and mechanical stress momentarily exceeded absolute maximum ratings may cause the permanent damages and may degrade the lifetime and safety for both device and system using the device in the field. The functional operation at or over these absolute maximum ratings is not assured. RECOMMENDED OPERATING CONDITIONS (ELECTRICAL CHARACTERISTICS) All of electronic equipment should be designed that the mounted semiconductor devices operate within the recommended operating conditions. The semiconductor devices cannot operate normally over the recommended operating conditions, even if when they are used over such conditions by momentary electronic noise or surge. And the semiconductor devices may receive serious damage when they continue to operate over the recommended operating conditions. 6

7 RP56K ELECTRICAL CHARACTERISTICS RP56Kxx1 (Ta=25ºC) Symbol Item Conditions Min. Typ. Max. Unit Istandby Standby Current AV IN / PV IN =5.5V, V CE =V 5 μa I CEH CE H Input Current AV IN / PV IN =V CE =5.5V -1 1 μa I CEL CE L Input Current AV IN / PV IN =5.5V, V CE =V -1 1 μa I MODEH MODE H Input Current AV IN / PV IN =V MODE =5.5V, V CE =V -1 1 μa I MODEL MODE L Input Current AV IN / PV IN =5.5V, V CE =V MODE =V -1 1 μa I LXLEAKH L X Leakage Current H AV IN / PV IN =V LX =5.5V, V CE =V -1 6 μa I LXLEAKL L X Leakage Current L AV IN / PV IN =5.5V, V CE =V LX =V -6 1 μa V CEH CE H Input Voltage AV IN / PV IN =5.5V 1. V V CEL CE L Input Voltage AV IN / PV IN =2.5V.4 V V MODEH MODE H Input Voltage AV IN / PV IN =5.5V 1. V V MODEL MODE L Input Voltage AV IN / PV IN =2.5V.4 V R ONP On Resistance of Pch Transistor AV IN / PV IN =3.6V, I LX =-1mA.13 Ω R ONN On Resistance of Nch Transistor AV IN / PV IN =3.6V, I LX =-1mA.125 Ω Maxduty Oscillator Maximum Duty Cycle 1 % tstart1 Soft-start Time 1 tstart2 Soft-start Time 2 AV IN / PV IN =V CE =3.6V or V SET +1V, T SS =OPEN AV IN / PV IN =V CE =3.6V or V SET +1V, C SS =.1μF 15 3 μs ms I LXLIM L X Current Limit AV IN / PV IN =V CE =3.6V or V SET +1V ma tprot Protection Delay Time AV IN / PV IN =V CE =3.6V or V SET +1V ms V UVLO1 UVLO Detector Threshold AV IN / PV IN =V CE V V UVLO2 UVLO Released Voltage AV IN / PV IN =V CE V T TSD Thermal Shutdown Temperature Junction Temperature 15 ºC T TSR R PG Thermal Shutdown Released Temperature On Resistance of PG Pin When Low Output Junction Temperature 1 ºC AV IN / PV IN =3.6V, V OUT =V or V FB =V 45 Ω RP56Kxx1A/ B/ C (Oscillator Frequency: 2.25MHz) When MODE=H 1.1V V SET <1.2V V IN Operating Input Voltage *11 1.2V V SET When MODE=L.8V V SET <1.V V Operating Input Voltage 1.V V SET fosc Oscillator Frequency AV IN / PV IN =V CE =3.6V or V SET +1V MHz RP56Kxx1D/ E/ F (Oscillator Frequency: 1.2MHz) When MODE=H.6V V SET <.7V V IN Operating Input Voltage.7V V SET V When MODE=L Operating Input Voltage f OSC Oscillator Frequency AV IN / PV IN =V CE =3.6V or V SET +1V MHz 7

8 RP56K Symbol Item Conditions Min. Typ. Max. Unit V OUT RP56Kxx1A/ B/ D/ E (Fixed Type) AV V SET 1.2V x x 1.15 IN / PV IN =V CE =3.6V or V SET +1V V SET <1.2V V ΔV OUT /ΔT Temperature Coefficient 4 C TTa 85 C ±1 ppm/ºc I DD1 Supply Current 1 AV IN / PV IN =V CE =5.5V, V OUT =V SET.8 6 μa I DD2 Supply Current 2 AV IN / PV IN =V CE V MODE =V μa =V OUT =5.5V V MODE =5.5V 6 μa I VOUTL V OUT L Current AV IN / PV IN =5.5V, V CE =V OUT =V -1 1 μa V OVD OVD Voltage AV IN / PV IN =3.6V V SET 1.2 V V UVD UVD Voltage AV IN / PV IN =3.6V V SET.8 V RP56Kxx1A/ D (Fixed Type without Auto-discharge Function) I VOUTH V OUT H Current AV IN / PV IN =V OUT =5.5V, V CE =V -1 1 μa RP56Kxx1B/ E (Fixed Type with Auto-discharge Function) R LOW On Resistance of Low Output AV IN / PV IN =3.6V, V CE =V 45 Ω RP56K1C/ F (Adjustable Type) V FB Feedback Voltage AV IN / PV IN =V CE =3.6V V ΔV FB /ΔT Feedback Voltage Temperature Coefficient 4 C TTa 85 C ±1 ppm/ºc I DD1 Supply Current 1 AV IN / PV IN =V CE =5.5V, V FB =.48V 6 μa I DD2 Supply Current 2 AV IN / PV IN =V CE V MODE =V μa =V FB =5.5V V MODE =5.5V 6 μa I VFBH V FB H Current AV IN / PV IN =V FB =5.5V, V CE =V -1 1 μa I VFBL V FB L Current AV IN / PV IN =5.5V, V CE =V FB =V -1 1 μa V OVD OVD Voltage AV IN / PV IN =3.6V.72 V V UVD UVD Voltage AV IN / PV IN =3.6V.48 V All test items listed under Electrical Characteristics are done under the pulse load condition (Tj Ta=25ºC) except Temperature Coefficient and Feedback Voltage Temperature Coefficient. *11 As for RP56Kxx1A/ B/ C (MODE=H), V SET can be set from 1.1V. 8

9 RP56K TYPICAL APPLICATION RP56Kxx1A/ B/ D/ E (Fixed Type) with PG Function, 3ms Soft-start Time V IN R PG 1kΩ PG C IN 1uF PV IN AV IN PG RP56K Series PGND L X AGND L1 2.2uH V OUT C OUT 3uF CE V OUT MODE *12 T SS C SS.1uF *12 MODE= L PWM/ VFM Auto Switching Control RP56K1C/ F (Adjustable Type) without PG Function, 15µs Soft-start-time V IN C IN 1uF PV IN PGND AV IN Lx RP56K Series PG AGND L2 2.2uH R1 C1 V OUT C OUT 3uF CE V FB MODE *12 T SS R2 *12 MODE= L PWM/ VFM Auto Switching Control Table 1. Recommended External Components Symbol Size Part Description Model C IN 1μF Ceramic Capacitor C168JBJ16M (TDK) JMK17BJ16MA (Taiyo Yuden) 22μF x 2 Ceramic Capacitor C212JBJ226M (TDK) C OUT C168JBJ16M (TDK) 1μF x 3 Ceramic Capacitor JMK17BJ16MA (Taiyo Yuden) SLF645T-2R2N3R3 (TDK) L 2.2μH Inductor CLF645-2R2N (TDK) FDSD415-2R2M (TOKO) RLF73T-2R2M5R4 (TDK) 9

10 RP56K TECHNICAL NOTES When using RP56K Series, please consider the following points. AGND and PGND must be wired to the GND plane when mounting on boards. AV IN and PV IN must be wired to the V IN plane when mounting on boards. Ensure the AV IN / PV IN and AGND/ PGND lines are sufficiently robust. A large switching current flows through the AGND/ PGND line, the V DD line, the V OUT line, an inductor, and L X. If their impedance is too high, noise pickup or unstable operation may result. Set the external components as close as possible to the IC and minimize the wiring between the components and the IC. Especially, place a capacitor (C IN ) as close as possible to the PV IN pin and PGND. For RP56Kxx1A/ B/ D/ E, separate the wiring between the V OUT pin and an inductor (L1) from the wiring between L1 and Load. Likewise, for RP56K1C/ F, separate the wiring between a resistor for setting output voltage (R1) and an inductor (L2) from the wiring between L2 and Load. Choose a low ESR ceramic capacitor. The ceramic capacitance of C IN should be more than or equal to 1µF. For a ceramic capacitor (C OUT ), it is recommended that three paralleled 1µF ceramic capacitors or two paralleled 22µF ceramic capacitors be used. Choose a 2.2µH inductor. The phase compensation of this IC is designed according to the C OUT and L values. Choose an inductor that has small DC resistance, has enough allowable current and is hard to cause magnetic saturation. If the inductance value of an inductor is extremely small, the peak current of L X may increase along with the load current. As a result, over current protection circuit may start to operate when the peak current of L X reaches to L X limit current. Over current protection circuit and latch type protection circuit may be affected by self-heating or power dissipation environment. The output voltage (V OUT ) is adjustable by changing the resistance values of resistors (R1, R2) as follows. V OUT = V FB (R1 + R2) / R2 (Recommended V OUT range for RP56K1F:.6V VSET 3.3V) (Recommended V OUT range for RP56K1C:.8V VSET 3.3V) If R1 and R2 are too large, the impedances of V FB also become large, as a result, the IC could be easily affected by noise. For this reason, R2 should be 22kΩ or less. If the operation becomes unstable dues to the high impedances, the impedances should be decreased. C1 can be calculated by the following equations. Please use the value close to the calculation result. C1 = / R2 [F] The recommended resistance values for R1 and C1 when R2=22kΩ are as follows. V SET [V] R1 [kω] R2 [kω] C1 [pf] Soft-start Time (tstart) is adjustable by connecting a capacitor (C SS ) between the T SS pin and GND. The capacitance value for C SS that is suitable for tstart can be calculated by the following equation. C SS (nf) = 3.5 tstart (ms) The T SS pin must be open if Soft-start time function is not used. Soft-start time is set to typically 15µs when the T SS pin is open. When using the power good function, the resistance value of a resistor (R PG ) should be between 1kΩ to 1kΩ. The PG pin must be open or connected to GND if the power good function is not used. For stable operation, please use recommended external components with recommended sizes indicated in Table 1. Recommended External Components. However, performances of power source circuits using RP56K largely depend on peripheral circuits. When selecting the peripheral components, please consider the conditions of use. Do not allow each component, PCB pattern or the IC to exceed their respected rated values (voltage, current, and power) when designing the peripheral circuits. 1

11 RP56K SOFT START TIME ADJUSTABLE FUNCTION AND POWER GOOD FUNCTION Soft-start Time Adjustable Function Soft-start time (tstart) of RP56K Series is adjustable by connecting a soft-start time adjustable capacitor (C SS ) between the T SS pin and GND. tstart can be set from Typ..15ms. As the diagram below shows, if.1µf C SS is connected, tstart will be 3ms. The T SS pin must be open if the soft-start time function is not used. tstart is set to.15ms (Typ.) when the T SS pin is open. tstart 3ms 15ms 3ms.15ms 47pF.1μF.47μF.1μF CSS C SS vs. tstart (Typ.) Power Good Function RP56K Series contains a power good function using Nch open drain. If any abnormal condition is detected, the power good function turns Nch transistor on and switches the PG pin to low. If the cause of the abnormal condition is removed, the power good function turns Nch transistor off and switches the PG pin back to high. After the recovery from abnormal condition, it takes typically.1ms for the IC to turns Nch transistor off. The followings are the abnormal conditions that the power good function can detect. CE= L (Shut down) UVLO (Shut down) Thermal Shutdown Over Voltage Detection: Typ. V SET x 1.2V (RP56Kxx1A/ B/ D/ E) or.72v (RP56K1C/ F) Under Voltage Detection: Typ. V SET x.8v (RP56Kxx1A/ B/ D/ E) or.48v (RP56K1C/ F) When using the power good function, the resistance of PG pin (R PG ) should be between 1kΩ to 1kΩ. The PG pin must be open or connected to GND if the power good function is not used. 11

12 RP56K START-UP SEQUENCE USING SOFT-START TIME ADJUSTABLE FUNCTION AND POWER GOOD FUNCTION Start-up sequence of RP56K Series can be built by using soft-start time adjustable function and power good function. The diagram below shows an example of circuits with start-up sequence using DC/ DC1 and DC/ DC2. In the circuits with start-up sequence, by sending the PG signal to the CE pin of DC/ DC2, DC/ DC1 starts up first and then DC/ DC2 starts up after. Circuits Example with Start-up Sequence DC/ DC1 (RP56K1C/F): V IN =5.V, V OUT =1.8V, tstart=3ms (C SS =.1μF) DC/ DC2 (RP56K1C/F): V IN =5.V, V OUT =1.2V, tstart=3ms (C SS =.1μF) V IN=5.V C IN1 1µH R PG1 1kΩ PV IN AV IN PG CE RP56K 1C/F DC/ DC1 PGND Lx AGND V FB L 1 2.2µH 44kΩ 22pF V OUT1 1.8V C OUT1 3µF MODE T SS 22kΩ C SS1.1µF PV IN PGND C IN2 1µH AV IN PG RP56K 1C/F DC/ DC2 Lx AGND L 2 2.2µH 22kΩ 22pF V OUT2 1.2V C OUT2 3µF CE V FB MODE T SS 22kΩ C SS2.1µF 12

13 RP56K OPERATION OF STEP-DOWN DC/ DC CONVERTER AND OUTPTUT CURRENT The step-down DC/ DC converter charges energy in the inductor when L X Tr. turns ON, and discharges the energy from the inductor when L X Tr. turns OFF and operates with less energy loss, so that a lower output voltage (V OUT ) than the input voltage (V IN ) can be obtained. The operation of the step-down DC/ DC converter is explained in the following diagrams. Diag. 1 Basic Circuit i1 Diag. 2 Inductor Current () Flowing through Inductor (L) max VIN Pch Tr Nch Tr L i2 CL VOUT min i1 i2 topen GND ton T=1/fosc toff Step1. Pch Tr. turns ON and (i1) flows, L is charged with energy. At this moment, i1 increases from the minimum inductor current (min), which is A, and reaches the maximum inductor current (max) in proportion to the on-time period (ton) of Pch Tr. Step2. When Pch Tr. turns OFF, L tries to maintain at max, so L turns Nch Tr. ON and (i2) flows into L. Step3. i2 decreases gradually and reaches min after the open-time period (topen) of Nch Tr., and then Nch Tr. turns OFF. This is called discontinuous current mode. As the output current (I OUT ) increases, the off-time period (toff) of Pch Tr. runs out before reaches min. The next cycle starts, and Pch Tr. turns ON and Nch Tr. turns OFF, which means starts increasing from min. This is called continuous current mode. In the case of PWM control system, V OUT is maintained by controlling ton. During PWM control, the oscillator frequency (fosc) is being maintained constant. As shown in Diag. 2, when the step-down DC/ DC operation is constant, min and max during ton of Pch Tr. would be same as during toff of Pch Tr. The current differential between max and min is described as ΔI. ΔI = max min = V OUT topen / L = (V IN V OUT ) ton / L Equation 1 However, T = 1 / fosc = ton + toff Duty (%)= ton / T 1 = ton fosc 1 topen toff In Equation 1, V OUT topen / L shows the amount of current change in "ON" state. Also, (V IN V OUT ) ton / L shows the amount of current change at "OFF" state. 13

14 RP56K Discontinuous Mode and Continuous Mode As illustrated in Diag 3., when I OUT is relatively small, topen<toff. In this case, the energy charged into L during ton will be completely discharged during toff, as a result, min=. This is called discontinuous mode. When I OUT is gradually increased, eventually topen=toff and when I OUT is increased further, eventually min>. This is called continuous mode. Diag 3. Discontinuous Mode Diag 4. Continuous Mode max max min topen min t Iconst t ton T=1/fosc toff ton T=1/fosc toff In the continuous mode, the solution of Equation 1 is described as tonc. tonc = T T V OUT / V IN Equation 2 When ton<tonc, it is discontinuous mode, and when ton tonc, it is continuous mode. 14

15 RP56K Forced PWM Mode By setting the MODE pin to H, the IC switches the frequency at the fixed rate to reduce noise even when the output load is light. Therefore, when I OUT is /2 or less, min becomes less than. That is, the accumulated electricity in CL is discharged through the IC side while is increasing from min to during ton, and also while is decreasing from to min during toff. Forced PWM Mode max Δ IOUT min t ton toff T=1/fosc VFM Mode By setting the MODE pin to L, in low output current, the IC automatically switches into VFM mode in order to achieve high efficiency. In VFM mode, ton is forced to end when the inductor current reaches the pre-set max. In the VFM mode, max is typically set to 4mA for RP56Kxx1A/ B/ C, and 55mA for RP56Kxx1D/ E/ F. When ton reaches 1.5 times of T=1/fosc, ton will be forced to end even if the inductor current is not reached max. VFM Mode max min t ton toff 15

16 RP56K OUTPUT CURRENT AND SELECTION OF EXTERNAL COMPONENTS The following equations explain the relationship between output current and peripheral components used in the diagram in TYPICAL APPLICATIONS (P.9). Ripple Current P-P value is described as I RP, ON resistance of Pch Tr. is described as R ONP, ON resistance of Nch Tr. is described as R ONN, and DC resistor of the inductor is described as R L. First, when Pch Tr. is ON, the following equation is satisfied. V IN = V OUT + (R ONP + R L ) I OUT + L I RP / ton Equation 3 Second, when Pch Tr. is "OFF" (Nch Tr. is "ON"), the following equation is satisfied. L I RP / toff = R ONN I OUT + V OUT + R L I OUT Equation 4 Put Equation 4 into Equation 3 to solve ON duty of Pch Tr. (D ON = ton / (toff + ton)): D ON = (V OUT + R ONN I OUT + R L I OUT )/(V IN + R ONN I OUT R ONP I OUT ) Equation 5 Ripple Current is described as follows: I RP = (V IN V OUT R ONP I OUT R L I OUT ) D ON / fosc / L Equation 6 Peak current that flows through L, and L X Tr. is described as follows: Xmax = I OUT + I RP / 2 Equation 7 Please consider xmax when setting conditions of input and output, as well as selecting the external components. The above calculation formulas are based on the ideal operation of the ICs in continuous mode. 16

17 RP56K TIMING CHART (1) Soft-start Time Starting-up with CE Pin The IC starts to operate when the CE pin voltage (V CE ) exceeds the threshold voltage. The threshold voltage is preset between CE H input voltage (V CEH ) and CE L input voltage (V CEL ). CE Pin Input Voltage (V CE) IC Internal Reference Voltage (V REF) Lx Voltage (V LX) (V OUT) V CEH Threshold Level V CEL Soft-start Circuit operation starts. Soft-start Time IC operates with PWM mode during Soft-start time. Depending on Power Supply, Load Current, External Components Soft-start time starts when soft-start circuit is activated, and ends when the reference voltage reaches the specified voltage. Soft start time is not always equal to the turn-on speed of the step-down DC/ DC converter. Please note that the turn-on speed could be affected by the power supply capacity, the output current, the inductance value and the C OUT value. Starting-up with Power Supply After the power-on, when V IN exceeds the UVLO released voltage (V UVLO2 ), the IC starts to operate. Then, soft-start circuit starts to operate and after a certain period of time, V REF gradually increases up to the specified value. Soft-start time starts when soft-start circuit is activated, and ends when V REF reaches the specified voltage. V SET Input Voltage (V IN) V UVLO2 V UVLO1 Soft-start Time IC Internal Reference Voltage (V REF) Lx Voltage (V LX) IC operates with PWM mode during Soft-start time. V SET (V OUT) Depending on Power Supply, Load Current, External Components Please note that the turn-on speed of V OUT could be affected by the power supply capacity, the output current, the inductance value, the C OUT value and the turn-on speed of V IN determined by C IN. 17

18 RP56K (2) Under Voltage Lockout (UVLO) Circuit If V IN becomes lower than V SET, the step-down DC/ DC converter stops the switching operation and ON duty becomes 1%, and then V OUT gradually drops according to V IN. If the V IN drops more and becomes lower than the UVLO detector threshold (V UVLO1 ), the UVLO circuit starts to operate, V REF stops, and Pch and Nch built-in switch transistors turn OFF. As a result, V OUT drops according to the C OUT capacitance value and the load. To restart the operation, V IN needs to be higher than V UVLO2. The timing chart below shows the voltage shifts of V REF, V LX and V OUT when V IN value is varied. Input Voltage (V IN) IC Internal Reference Voltage V SET V UVLO2 V UVLO1 (V REF) Soft-start Time Lx Voltage (V LX) (V OUT) V SET Depending on Power Supply, Load Current, External Components Falling edge (operating) and rising edge (releasing) waveforms of V OUT could be affected by the initial voltage of C OUT and the output current of V OUT. 18

19 RP56K (3) Over Current Protection Circuit, Latch Type Protection Circuit Over current protection circuit supervises the inductor peak current (the peak current flowing through Pch Tr.) in each switching cycle, and if the current exceeds the L X current limit (I LXLIM ), it turns off Pch Tr. I LXLIM of the RP56K is set to Typ.28mA. Latch type protection circuit latches the built-in driver to the OFF state and stops the operation of the step-down DC/ DC converter if the over current status continues or V OUT continues being the half of the setting voltage for equal or longer than protection delay time (tprot). Notes: I LXLIM and tprot could be easily affected by self-heating or ambient environment. If the V IN drops dramatically or becomes unstable due to short-circuit, protection operation and tprot could be affected. Protection Delay Time (tprot) flowing through L Current flowing through Pch Tr. Lx Limit Current (I LXLIM) Lx Voltage (V LX) To release the latch type protection circuit, restart the IC by inputting "L" signal to the CE pin, or restart the IC with power-on or make the supply voltage lower than V UVLO1. The timing chart below shows the voltage shift of V CE, V LX and V OUT when the IC status is changed by the following orders: V IN rising stable operation high load CE reset stable operation V IN falling V IN recovering stable operation. (1) If the large current flows through the circuit or the IC goes into low V OUT condition due to short-circuit or other reasons, the latch type protection circuit latches the built-in driver to OFF state after tprot. Then, V LX becomes "L" and V OUT turns OFF. In this timing chart below, the latch protection circuit is released by once setting the IC into "L" with the CE pin and then setting it back to "H". (2) The latch type protection is released by UVLO reset, which makes V IN lower than V UVLO1. (1) (2) V SET Input Voltage (V UVLO Released Voltage (V IN) UVLO2 ) UVLO Detector Thresholds (V UVLO1 ) CE Pin Input Voltage (V CE) V SET Threshold Level Protection Delay Time CE Reset UVLO Reset Protection Delay Time Lx Voltage V SET (V LX) (V OUT) V SET Latch-type Protection Latch-type Protection Stable Stable Operation Operation Soft-start Time Soft-start Time Stable Operation Soft-start Time 19

20 RP56K TYPICAL PERFORMANCE CHARACTERISTICS 1) vs. RP56Kxx1A/B/C VOUT=1.2V RP56Kxx1A/B/C VOUT=1.2V V OUT(V) V OUT(V) Vin=3.6V Vin=5.V RP56Kxx1A/B/C VOUT=1.8V Vin=3.6V Vin=5.V RP56Kxx1A/B/C VOUT=3.3V V OUT(V) V OUT(V) Vin=3.6V Vin=5.V RP56Kxx1A/B/C VOUT=1.8V Vin=3.6V Vin=5.V RP56Kxx1A/B/C VOUT=3.3V V OUT(V) Vin=4.3V Vin=5.V V OUT(V) Vin=4.3V Vin=5.V

21 RP56K RP56Kxx1D/E/F VOUT=.6V RP56Kxx1D/E/F VOUT=.6V V OUT(V) Vin=3.6V.585 Vin=4.5V V OUT(V) Vin=3.6V Vin=4.5V RP56Kxx1D/E/F VOUT=.8V RP56Kxx1D/E/F VOUT=.8V V OUT(V) Vin=3.6V Vin=5.V V OUT(V) Vin=3.6V Vin=5.V RP56Kxx1D/E/F VOUT=1.2V RP56Kxx1D/E/F VOUT=1.2V V OUT(V) Vin=3.6V Vin=5.V V OUT(V) Vin=3.6V Vin=5.V

22 RP56K RP56Kxx1D/E/F VOUT=1.8V RP56Kxx1D/E/F VOUT=1.8V V OUT(V) Vin=3.6V Vin=5.V V OUT(V) Vin=3.6V Vin=5.V RP56Kxx1D/E/F VOUT=3.3V RP56Kxx1D/E/F VOUT=3.3V V OUT(V) Vin=4.3V Vin=5.V ) vs. Input Voltage RP56Kxx1D/E/F VOUT=.6V V OUT(V) Vin=4.3V Vin=5.V RP56Kxx1D/E/F VOUT=.8V V OUT(V) Iout=1mA Iout=1mA V OUT(V) Iout=1mA Iout=1mA.585 Iout=2mA.785 Iout=2mA Input Voltage VIN(V) Input Voltage VIN(V) 22

23 RP56K RP56K VOUT=1.2V RP56K VOUT=1.8V V OUT(V) Iout=1mA 1.19 Iout=1mA Iout=2mA Input Voltage VIN(V) V OUT(V) Iout=1mA 1.79 Iout=1mA Iout=2mA Input Voltage VIN(V) RP56K VOUT=3.3V V OUT(V) Iout=1mA 3.33 Iout=1mA 3.32 Iout=2mA Input Voltage VIN(V) 3) vs. Ambient Temperature 4) Feedback Voltage vs. Ambient Temperature RP56K181A/B/D/E VOUT=1.8V RP56K1C/F V OUT(V) Vin=3.6V Feedback Voltage V FB (V) Vin=3.6V Temperature Ta ( ) Temperature Ta ( ) 23

24 RP56K 5) Efficiency vs. RP56Kxx1A/B/C VOUT=1.2V RP56Kxx1A/B/C VOUT=1.8V VIN=3.6V, VMODE=V VIN=5.V, VMODE=V VIN=5.V, VMODE=V VIN=3.6V, VMODE=V Efficiency (%) VIN=VMODE=5.V Efficiency (%) VIN=VMODE=5.V 2 1 VIN=VMODE=3.6V 2 1 VIN=VMODE=3.6V RP56Kxx1A/B/C VOUT=3.3V VIN=4.3V, VMODE=V Efficiency (%) VIN=5.V, VMODE=V VIN=VMODE=5.V 2 1 VIN=VMODE=4.3V RP56Kxx1D/E/F VOUT=.6V RP56Kxx1D/E/F VOUT=.8V VIN=4.5V, VMODE=V VIN=3.6V, VMODE=V VIN=5.V, VMODE=V VIN=3.6V, VMODE=V 7 7 Efficiency (%) VIN=VMODE=4.5V Efficiency (%) VIN=VMODE=5.V 2 1 VIN=VMODE=3.6V 2 1 VIN=VMODE=3.6V

25 RP56K RP56Kxx1D/E/F VOUT=1.2V RP56Kxx1D/E/F VOUT=1.8V VIN=3.6V, VMODE=V VIN=5.V, VMODE=V VIN=5.V, VMODE=V VIN=3.6V, VMODE=V Efficiency (%) VIN=VMODE=5.V Efficiency (%) VIN=VMODE=5.V 2 1 VIN=VMODE=3.6V 2 1 VIN=VMODE=3.6V RP56Kxx1D/E/F VOUT=3.3V VIN=4.3V, VMODE=V Efficiency (%) VIN=5.V, VMODE=V VIN=VMODE=5.V 2 1 VIN=VMODE=4.3V ) Supply Current vs. Ambient Temperature 7) Supply Current vs. Input Voltage RP56K VOUT=1.8V(VIN=5.5V) RP56K VOUT=1.8V Supply Current (ua) Supply Current (ua) Closed Loop 4 Closed Loop Open Loop Open Loop Temperature Ta ( C) Input Voltage VIN (V) 25

26 RP56K 8) Waveform Output Ripple Voltage(AC) Vripple (V) RP56Kxx1A/B/C VOUT=.8V(VIN=3.6V) I OUT =1mA Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) RP56Kxx1A/B/C VOUT=1.2V(VIN=3.6V) I OUT =1mA RP56Kxx1A/B/C VOUT=1.8V(VIN=3.6V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) RP56Kxx1A/B/C VOUT=1.2V(VIN=3.6V) I OUT =1mA RP56Kxx1A/B/C VOUT=1.8V(VIN=3.6V) Inductor Current (ma) I OUT =1mA 5 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) 26

27 RP56K RP56Kxx1A/B/C VOUT=3.3V(VIN=5.V) RP56Kxx1A/B/C VOUT=1.8V(VIN=5.V) I OUT =1mA 5 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) RP56Kxx1D/E/F VOUT=.6V(VIN=3.6V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) RP56Kxx1D/E/F VOUT=.6V(VIN=3.6V) Inductor Current (ma) I OUT =1mA 8 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) RP56Kxx1D/E/F VOUT=.8V(VIN=3.6V) RP56Kxx1D/E/F VOUT=.8V(VIN=3.6V) I OUT =1mA 8 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma)

28 RP56K RP56Kxx1D/E/F VOUT=1.2V(VIN=3.6V) RP56Kxx1D/E/F VOUT=1.2V(VIN=3.6V) I OUT =1mA 8 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) RP56Kxx1D/E/F VOUT=1.8V(VIN=3.6V) RP56Kxx1D/E/F VOUT=1.8V(VIN=3.6V) I OUT =1mA 8 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) RP56Kxx1D/E/F VOUT=3.3V(VIN=5.V) RP56Kxx1D/E/F VOUT=3.3V(VIN=5.V) I OUT =1mA 8 I OUT =1mA Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma) Output Ripple Voltage(AC) Vripple (V) Inductor Current (ma)

29 RP56K 9) Oscillator Frequency vs. Ambient Temperature RP56Kxx1A/B/C RP56Kxx1D/E/F Frequency fosc (MHz) Vin=3.6 Frequency fosc (MHz) Vin= Temperature Ta ( C) 1) Oscillator Frequency vs. Input Voltage RP56Kxx1A/B/C Temperature Ta ( C) 1.4 RP56Kxx1D/E/F Frequency fosc (MHz) C 25 C 85 C Frequency fosc (MHz) C 25 C 85 C Input Voltage VIN (V) Input Voltage VIN (V) 11) Soft-start Time vs. Ambient Temperature Soft Start Time tstart1 (us) Temperature Ta ( ) 29

30 RP56K 12) UVLO Detector Threshold/ Released Voltage vs. Ambient Temperature UVLO Detector Threshold UVLO Released Voltage UVLO Voltage V UVLO1 (V) Temperature ( ) UVLO Voltage V UVLO2 (V) Temperature ( ) 13) CE Input Voltage vs. Ambient Temperature CE H Input Voltage (VIN=5.5V) CE L Input Voltage (VIN=2.5V) CE Input Voltage V CEH (V) CE Input Voltage V CEL (V) Temperature ( ) Temperature ( ) 14) Lx Limit Current vs. Ambient Temperature 33 LX Limit Current I LXLIM (ma) Temperature ( ) 3

31 RP56K 15) Nch Tr. On Resistance vs. Ambient Temperature 16) Pch Tr. On Resistance vs. Ambient Temperature Nch Tr. ON Resistance R ON (Ω) Temperature ( ) Pch Tr. ON Resistance R ON (Ω) Temperature ( ) 17) PG Detector Threshold vs. Ambient Temperature Over Voltage Detection (VOVD) Under Voltage Detection (VUVD) VSET 1.3 VSET.9 PG Over Voltage Detection VOVD Voltage (VSET Y) PG Under Voltage Detection VUVD Voltage (VSET Y) VSET Temperature ( ) VSET Temperature ( ) 18) Soft-start Waveform RP56K VOUT=1.8V T SS =Open RP56K VOUT=1.8V T SS =.1μF 6 4 CE Input Voltage 6 4 CE Input Voltage CE Input Voltage (V) 2 PG Voltage (V) PG Voltage (V) CE Input Voltage (V) 2 PG Voltage (V) PG Voltage (V) Time t (ms) -1 31

32 RP56K 19) Load Transient Response RP56Kxx1A/B/C (VIN=3.6V, VOUT=.8V) 15 RP56Kxx1A/B/C (VIN=3.6V, VOUT=.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1A/B/C (VIN=3.6V, VOUT=.8V) 3 RP56Kxx1A/B/C (VIN=3.6V, VOUT=.8V) 3 V OUT (V) mA-->2mA 2 1 V OUT (V) mA-->1mA

33 RP56K RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) 15 RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V) 3 V OUT (V) mA-->2mA 2 1 V OUT (V) mA-->1mA

34 RP56K RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) 15 RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V) 3 2 2mA-->1mA 2 V OUT (V) mA-->2mA 1 V OUT (V)

35 RP56K RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) 15 RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA V OUT (V) RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) 2mA-->1mA RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) V OUT (V) RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) 1mA-->2mA RP56Kxx1A/B/C (VIN=5.V, VOUT=3.3V) mA-->1mA 2 V OUT (V) V OUT (V)

36 RP56K RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) 15 RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=.6V) 3 V OUT (V) mA-->2mA 2 1 V OUT (V) mA-->1mA

37 RP56K RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) 15 RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=.8V) 3 2 2mA-->1mA 2 V OUT (V) mA-->2mA 1 V OUT (V)

38 RP56K RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) 15 RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V) 3 V OUT (V) mA-->2mA 2 1 V OUT (V) mA-->1mA

39 RP56K RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) 15 RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V) 3 V OUT (V) mA-->2mA 2 1 V OUT (V) mA-->1mA

40 RP56K RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) 15 RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) 15 V OUT (V) mA-->1mA 1 5 V OUT (V) mA-->2mA RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) RP56Kxx1D/E/F (VIN=5.V, VOUT=3.3V) mA-->1mA 2 V OUT (V) mA-->2mA 1 V OUT (V)

41 RP56K 2) Auto Switching Control Waveform RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V, IOUT=1mA) MODE= L --> MODE= H 6 RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.2V, IOUT=1mA) MODE= H --> MODE= L 6 V OUT (V) Mode Input Voltage 4 2 Mode Input Voltage V MODE(V) V OUT (V) Mode Input Voltage 4 2 Mode Input Voltage V MODE(V) RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V, IOUT=1mA) MODE= L --> MODE= H 6 RP56Kxx1A/B/C (VIN=3.6V, VOUT=1.8V, IOUT=1mA) MODE= H --> MODE= L 6 V OUT (V) 4 2 Mode Input Voltage Mode Input Voltage V MODE(V) V OUT (V) 4 Mode Input Voltage Mode Input Voltage V MODE(V) RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V, IOUT=1mA) MODE= L --> MODE= H 6 RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.2V, IOUT=1mA) MODE= H --> MODE= L 6 V OUT (V) Mode Input Voltage 4 2 Mode Input Voltage V MODE (V) V OUT (V) Mode Input Voltage 4 2 Mode Input Voltage V MODE V)

42 RP56K RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V, IOUT=1mA) MODE= L --> MODE= H 6 RP56Kxx1D/E/F (VIN=3.6V, VOUT=1.8V, IOUT=1mA) MODE= H --> MODE= L 6 V OUT (V) 4 Mode Input Voltage Mode Input Voltage V MODE (V) V OUT (V) 4 Mode Input Voltage Mode Input Voltage V MODE (V) 42

43 Ricoh presented with the Japan Management Quality Award for Ricoh continually strives to promote customer satisfaction, and shares the achievements of its management quality improvement program with people and society. Ricoh awarded ISO 141 certification. The Ricoh Group was awarded ISO 141 certification, which is an international standard for environmental management systems, at both its domestic and overseas production facilities. Our current aim is to obtain ISO 141 certification for all of our business offices. Ricoh completed the organization of the Lead-free production for all of our products. After Apr. 1, 26, we will ship out the lead free products only. Thus, all products that will be shipped from now on comply with RoHS Directive.