RT8008-18QJ5

RT8008 1.5MHz, 600mA, High Efficiency PWM Step-Down DC/DC Converter General Description The RT8008 is a high-efficiency pulse-width-modulated (PWM) step-down DC-DC converter. Capable of delivering 600mA output current over a wide input voltage range from 2.5V to 5.5V, the RT8008 is ideally suited for portable electronic devices that are powered from 1-cell Li-ion battery or from other power sources within the range such as cellular phones, PDAs and handy-terminals. Internal synchronous rectifier with low RDS(ON) dramatically reduces conduction loss at PWM mode. No external Schottky diode is required in practical application. The RT8008 automatically turns off the synchronous rectifier while the inductor current is low and enters discontinuous PWM mode. This can increase efficiency at light load condition. The RT8008 enters Low-Dropout mode when normal PWM cannot provide regulated output voltage by continuously turning on the upper P-MOSFET. RT8008 enter shutdown mode and consumes less than 0.1µA when EN pin is pulled low. The switching ripple is easily smoothed-out by small package filtering elements due to a fixed operation frequency of 1.5MHz. This along with small SOT-23-5 and TSOT-23-5 package provides small PCB area application. Other features include soft start, lower internal reference voltage with 2% accuracy, over temperature protection, and over current protection. Features l l l l l l l l l +2.5V to +5.5V Input Range Adjustable Output From 0.6V to VIN 1.0V, 1.2V, 1.5V, 1.8V, 2.5V and 3.3V Fixed/ Adjustable Output Voltage 600mA Output Current, 1A Peak Current 95% Efficiency No Schottky Diode Required 1.5MHz Fixed-Frequency PWM Operation Small SOT-23-5 and TSOT-23-5 Package RoHS Compliant and 100% Lead (Pb)-Free Applications l l l l l Cellular Telephones Personal Information Appliances Wireless and DSL Modems MP3 Players Portable Instruments Ordering Information RT8008() Package Type B : SOT-23-5 J5 : TSOT-23-5 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commercial Standard) Output Voltage Default : Adjustable 10 : 1.0V 12 : 1.2V 15 : 1.5V 18 : 1.8V 25 : 2.5V 33 : 3.3V Note : RichTek Pb-free and Green products are : Pin Configurations (TOP VIEW) EN GND LX 1 2 3 4 VIN 5 FB/VOUT }RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. SOT-23-5/TSOT-23-5 }Suitable for use in SnPb or Pb-free soldering processes. }100% matte tin (Sn) plating. DS8008-04 March 2007 www.richtek.com 1 RT8008 Typical Application Circuit 4 CIN 4.7uF 1 EN 3 L 2.2uH VOUT VIN 2.2V to 5.5V VIN RT8008 LX VOUT GND 2 5 COUT 10uF Figure 1. Fixed Voltage Regulator L 2.2uH VOUT C1 R1 5 IR2 R2 COUT 10uF VIN 2.2V to 5.5V 4 CIN 4.7uF 1 VIN LX 3 RT8008 EN GND 2 FB V OUT = V REF R1   x 1 +  R2   with R2 = 300kΩ to 60kΩ so the IR2 = 2µA to 10µA, and (R1 x C1) should be in the range between 3x10-6 and 6x10-6 for component selection. Figure 2. Adjustable Voltage Regulator Layout Guide VIN GND CIN COUT VOUT VIN CIN GND C OUT VOUT L VIN 4 3 2 VOUT 5 1 LX GND C1 EN R1 GND VOUT FB R2 GND 5 1 EN VIN 4 3 2 LX GND L Figure 3 Layout note: 1. The distance that CIN c onnects to VIN is as close as possible (Under 2mm). 2. COUT should be placed near RT8008. www.richtek.com 2 DS8008-04 March 2007 RT8008 Functional Pin Description Pin Number 1 2 3 4 5 Pin Name EN GND LX VIN FB/VOUT Pin Function Chip Enable (Active High, do not leave EN pin floating, and VEN < VIN + 0.6V). Ground. Pin for Switching. Power Input. Feedback Input Pin. Function Block Diagram EN VIN OSC & Shutdown Control Slope Compensation Current Sense RS1 Current Limit Detector FB/VOUT Error Amplifier RC COMP PWM Comparator Control Logic Driver LX UVLO & Power Good Detector Zero Detector VREF RS2 GND DS8008-04 March 2007 www.richtek.com 3 RT8008 Absolute Maximum Ratings l l l (Note 1) l l l l l Supply Input Voltage ---------------------------------------------------------------------------------------------------- 6.5V Enable, FB Voltage ------------------------------------------------------------------------------------------------------ V IN + 0.6V Power Dissipation, PD @ TA = 25°C SOT-23-5, TSOT-23-5 --------------------------------------------------------------------------------------------------- 0.4W Package Thermal Resistance (Note 4) SOT-23-5, TSOT-23-5, θJA ---------------------------------------------------------------------------------------------- 250°C/W SOT-23-5, TSOT-23-5, θJC --------------------------------------------------------------------------------------------- 130°C/W Junction Temperature Range ------------------------------------------------------------------------------------------ 150°C Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------ 260°C Storage Temperature Range ------------------------------------------------------------------------------------------- −65°C to 150°C ESD Susceptibility (Note 2) HBM (Human Body Mode) --------------------------------------------------------------------------------------------- 2kV MM (Machine Mode) ---------------------------------------------------------------------------------------------------- 200V (Note 3) Recommended Operating Conditions l l l Supply Input Voltage ---------------------------------------------------------------------------------------------------- 2.5V to 5.5V Junction Temperature Range ------------------------------------------------------------------------------------------ −40°C to 125°C Ambient Temperature Range ------------------------------------------------------------------------------------------ −40°C to 85°C Electrical Characteristics (V IN = 3.6V, VOUT = 2.5V, VREF = 0.6V, L = 2.2µH, CIN = 4 .7µF, COUT = 1 0µF, TA = 2 5°C, IMAX = 600mA unless otherwise specified) Parameter Input Voltage Range Quiescent Current Shutdown Current Reference Voltage Adjustable Output Range Symbol VIN IQ ISHDN VREF VOUT ∆VOUT ∆VOUT ∆VOUT Test Conditions Min 2.5 Typ -50 0.1 0.6 ---------- M ax 5.5 100 1 0.612 VIN − 0.2 +3 +3 +3 +3 +3 +3 +3 +3 Units V µA µA V V % % % % % % % % IOUT = 0mA, VFB = VREF + 5% EN = GND For adjustable output voltage --0.588 VREF VIN = 2.2 to 5.5V, VOUT = 1.0V 0A < IOUT < 600mA VIN = 2.2 to 5.5V, VOUT = 1.2V 0A < IOUT < 600mA VIN = 2.2 to 5.5V, VOUT = 1.5V 0A < IOUT < 600mA VIN = 2.2 to 5.5V, VOUT = 1.8V 0A < IOUT < 600mA VIN = 2.8 to 5.5V, VOUT = 2.5V 0A < IOUT < 600mA VIN = 3.5 to 5.5V, VOUT = 3.3V 0A < IOUT < 600mA VIN = VOUT + 0.2V to 5.5V, V IN ≧ 3.5V 0A < IOUT < 600mA VIN = VOUT + 0.4V to 5.5V, V IN ≧ 2.2V 0A < IOUT < 600mA −3 −3 −3 −3 −3 −3 −3 −3 Fix ∆VOUT Output Voltage Accuracy ∆VOUT ∆VOUT Adjustable ∆VOUT To be continued www.richtek.com 4 DS8008-04 March 2007 RT8008 Parameter FB Input Current PMOSFET RON Symbol IFB VFB = VIN VIN = 3.6V VIN = 2.5V VIN = 3.6V VIN = 2.5V T est Conditions Min −50 ----1 1.5 ---fOSC TSD VIN = 3.6V, IOUT = 100mA 1.2 --100 VIN = 3.6V, VLX = 0V or VLX = 3.6V −1 Typ -0.3 0.4 0.25 0.35 ---1.8 0.1 1.5 160 50 --M ax 50 ----1.8 -0.4 --1.8 ---1 Units nA Ω Ω A V V V V MHz °C ns % µA PRDS(ON) IOUT = 200mA NMOSFET RON P-Channel Current Limit EN High-Level Input Voltage EN Low-Level Input Voltage Undervoltage Lock Out threshold H ysteresis Oscillator Frequency Thermal Shutdown Temperature Min. On Time Max. Duty Cycle LX Leakage Current NRDS(ON) IOUT = 200mA IP(LM) VENH VENL VIN = 2.5V to 5.5 V VIN = 2.5V to 5.5V VIN = 2.5V to 5.5V Note 1. S tresses listed as the above “ Absolute Maximum Ratings” may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. D evices are ESD sensitive. Handling precaution recommended. Note 3. T he device is not guaranteed to function outside its operating conditions. Note 4. θJA is measured in the natural convection at TA = 2 5°C on a low effective single layer thermal conductivity test board of JEDEC 51-3 thermal measurement standard. Pin 2 of SOT-23-5/TSOT-23-5 packages is the case position for θJC measurement. DS8008-04 March 2007 www.richtek.com 5 RT8008 Typical Operating Characteristics Efficiency vs. Load Current 100 90 100 Efficiency vs. Input Voltage IOUT = 300mA VIN = 3.3V 90 E fficie ncy (%) Efficienc y (%) 80 70 60 50 80 IOUT = 600mA 70 60 50 VIN = 5V VOUT = 1.2V 40 0.01 40 0.11 0.21 0.31 0.41 0.51 0.61 2.5 3 3.5 4 4.5 VOUT = 1.2V 5 5.5 Load Current (A) Input Voltage (V) Output Voltage vs. Load Current 1.220 1.215 2.0 2.5 Current Limit vs. Input Voltage O utpu t Vo ltage (V) 1.210 1.205 1.200 1.195 1.190 1.185 VIN = 5V C urre nt L imit (A) VIN = 3.3V 1.5 VIN = 2.5V 1.0 0.5 VOUT = 1.2V 1.180 0 0.1 0.2 0.3 0.4 0.5 0.6 0.0 2.5 3 3.5 4 4.5 VOUT = 1.2V 5 5.5 Load Current (A) Input Voltage (V) Frequency vs. Input Voltage 1.50 1.48 1.50 Frequency vs. Temperature VOUT = 1.2V, IOUT = 300mA 1.48 Fre que ncy (MHz) Fre que ncy (MHz) VOUT = 1.2V, IOUT = 300mA 1.45 1.43 1.40 1.38 1.35 2.5 3 3.5 4 4.5 5 5.5 1.45 1.43 1.40 1.38 1.35 -50 -25 0 25 50 75 100 125 Input Voltage (V) Temperature (°C) www.richtek.com 6 DS8008-04 March 2007 RT8008 Reference Voltage vs. Input Voltage 0.6010 1.25 Output Voltage vs. Temperature Re fere nce Voltage (V) 1.23 Outp ut Volta ge (V) VOUT = 1.2V 0.6005 1.21 0.6000 1.19 0.5995 1.17 VIN = 3.3V, IOUT = 0A 1.15 -50 -25 0 25 50 75 100 125 0.5990 2.5 3 3.5 4 4.5 5 5.5 Input Voltage (V) Temperature (°C) Load Transient Response VIN = 3.3V, VOUT = 1.2V, IOUT = 200mA to 600mA Load Transient Response VIN = 3.3V, VOUT = 1.2V, IOUT = 300mA to 600mA VOUT (20mV/Div) VOUT (20mV/Div) IOUT (500mA/Div) Time (50 µs/Div) IOUT (500mA/Div) Time (50 µs/Div) Output Ripple VIN = 3.3V, VOUT = 1.2V, IOUT = 600mA Power On VIN = 3.3V, VOUT = 1.2V, IOUT = 600mA VOUT (5mV/Div) VEN (2V/Div) VLX (5V/Div) VOUT (500mV/Div) II N (200mA/Div) Time (500ns/Div) Time (100 µs/Div) ILX (500mA/Div) DS8008-04 March 2007 www.richtek.com 7 RT8008 Power Off VIN = 3.3V, VOUT = 1.2V, IOUT = 600mA VEN (2V/Div) VOUT (500mV/Div) II N (200mA/Div) Time (100 µs/Div) www.richtek.com 8 DS8008-04 March 2007 RT8008 Applications Information The basic RT8008 application circuit is shown in Typical Application Circuit. External component selection is determined by the maximum load current and begins with the selection of the inductor value and operating frequency followed by CIN and COUT. Inductor Selection For a given input and output voltage, the inductor value and operating frequency determine the ripple current. The ripple current ∆IL increases with higher VIN and decreases with higher inductance.   V V ΔIL =  OUT  1 − OUT  VIN   f × L  Having a lower ripple current reduces the ESR losses in the output capacitors and the output voltage ripple. Highest efficiency operation is achieved at low frequency with small ripple current. This, however, requires a large inductor. A reasonable starting point for selecting the ripple current is ∆IL = 0.4(IMAX). The largest ripple current occurs at the highest VIN. To guarantee that the ripple current stays below a specified maximum, the inductor value should be chosen according to the following equation :  VOUT  VOUT  L= 1− f × ∆IL(MAX)   VIN(MAX)     current is exceeded. This results in an abrupt increase in inductor ripple current and consequent output voltage ripple. Do not allow the core to saturate! Different core materials and shapes will change the size/ current and price/current relationship of an inductor. Toroid or shielded pot cores in ferrite or permalloy materials are small and don’ t radiate energy but generally cost more than powdered iron core inductors with similar characteristics. The choice of which style inductor to use mainly depends on the price vs size requirements and any radiated field/EMI requirements. CIN and COUT Selection The input capacitance, CIN, is needed to filter the trapezoidal current at the source of the top MOSFET. To prevent large ripple voltage, a low ESR input capacitor sized for the maximum RMS current should be used. RMS current is given by : IRMS = IOUT(MAX) VOUT VIN VIN −1 VOUT Inductor Core Selection Once the value for L is known, the type of inductor must be selected. High efficiency converters generally cannot afford the core loss found in low cost powdered iron cores, forcing the use of more expensive ferrite or mollypermalloy cores. Actual core loss is independent of core size for a fixed inductor value but it is very dependent on the inductance selected. As the inductance increases, core losses decrease. Unfortunately, increased inductance requires more turns of wire and therefore copper losses will increase. Ferrite designs have very low core losses and are preferred at high switching frequencies, so design goals can concentrate on copper loss and preventing saturation. Ferrite core material saturates “ hard” , which means that inductance collapses abruptly when the peak design This formula has a maximum at VIN = 2VOUT , where IRMS = IOUT /2. This simple worst-case condition is commonly used for design because even significant deviations do not offer much relief. Note that ripple current ratings from capacitor manufacturers are often based on only 2000 hours of life which makes it advisable to further derate the capacitor, or choose a capacitor rated at a higher temperature than required. Several capacitors may also be paralleled to meet size or height requirements in the design. The selection of COUT is determined by the effective series resistance (ESR) that is required to minimize voltage ripple and load step transients, as well as the amount of bulk capacitance that is necessary to ensure that the control loop is stable. Loop stability can be checked by viewing the load transient response as described in a later section. The output ripple, ∆VOUT , is determined by :  1 ΔVOUT ≤ ΔIL ESR + 8fCOUT    The output ripple is highest at maximum input voltage since ∆IL increases with input voltage. Multiple capacitors placed in parallel may be needed to meet the ESR and RMS current handling requirements. Dry tantalum, special www.richtek.com 9 DS8008-04 March 2007 RT8008 polymer, aluminum electrolytic and ceramic capacitors are all available in surface mount packages. Special polymer capacitors offer very low ESR but have lower capacitance density than other types. Tantalum capacitors have the highest capacitance density but it is important to only use types that have been surge tested for use in switching power supplies. Aluminum electrolytic capacitors have significantly higher ESR but can be used in cost-sensitive applications provided that consideration is given to ripple current ratings and long term reliability. Ceramic capacitors have excellent low ESR characteristics but can have a high voltage coefficient and audible piezoelectric effects. The high Q of ceramic capacitors with trace inductance can also lead to significant ringing. Using Ceramic Input and Output Capacitors Higher values, lower cost ceramic capacitors are now becoming available in smaller case sizes. Their high ripple current, high voltage rating and low ESR make them ideal for switching regulator applications. However, care must be taken when these capacitors are used at the input and output. When a ceramic capacitor is used at the input and the power is supplied by a wall adapter through long wires, a load step at the output can induce ringing at the input, VIN. At best, this ringing can couple to the output and be mistaken as loop instability. At worst, a sudden inrush of current through the long wires can potentially cause a voltage spike at VIN large enough to damage the part. Output Voltage Programming The resistive divider allows the VFB pin to sense a fraction of the output voltage as shown in Figure 4. VOUT Efficiency Considerations The efficiency of a switching regulator is equal to the output power divided by the input power times 100%. It is often useful to analyze individual losses to determine what is limiting the efficiency and which change would produce the most improvement. Efficiency can be expressed as : Efficiency = 100% − (L1+ L2+ L3+ ...) where L1, L2, etc. are the individual losses as a percentage of input power. Although all dissipative elements in the circuit produce losses, two main sources usually account for most of the losses : VIN quiescent current and I2R losses. The VIN quiescent current loss dominates the efficiency loss at very low load currents whereas the I2R loss dominates the efficiency loss at medium to high load currents. In a typical efficiency plot, the efficiency curve at very low load currents can be misleading since the actual power lost is of no consequence. 1. The VIN quiescent current is due to two components : the DC bias current as given in the electrical characteristics and the internal main switch and synchronous switch gate charge currents. The gate charge current results from switching the gate capacitance of the internal power MOSFET switches. Each time the gate is switched from high to low to high again, a packet of charge ∆Q moves from VIN to ground. The resulting ∆Q/∆t is the current out of VIN that is typically larger than the DC bias current. In continuous mode, IGATECHG = f(QT+QB) where QT and QB are the gate charges of the internal top and bottom switches. Both the DC bias and gate charge losses are proportional to VIN and thus their effects will be more pronounced at higher supply voltages. 2. I2R losses are calculated from the resistances of the internal switches, RSW and external inductor RL. In continuous mode the average output current flowing through inductor L is “chopped” between the main switch and the synchronous switch. Thus, the series resistance looking into the LX pin is a function of both top and bottom MOSFET RDS(ON) and the duty cycle (DC) as follows : RSW = RDS(ON)TOP x DC + RDS(ON)BOT x (1−DC) The RDS(ON) for both the top and bottom MOSFETs can be obtained from the Typical Performance Characteristics DS8008-04 March 2007 R1 FB RT8008 GND R2 Figure 4. Setting the Output Voltage For adjustable about voltage mode, the output voltage is set by an external resistive divider according to the following equation : V R1 ) OUT = VREF (1 + R2 where VREF is the internal reference voltage (0.6V typ.) www.richtek.com 10 RT8008 curves. Thus, to obtain I2R losses, simply add RSW to RL and multiply the result by the square of the average output current. Other losses including CIN and COUT ESR dissipative losses and inductor core losses generally account for less than 2% of the total loss. Thermal Considerations The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference between junction to ambient. The maximum power dissipation can be calculated by following formula : PD(MAX) = ( TJ(MAX) - TA ) / θJA Where T J(MAX) i s the maximum operation junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. For recommended operating conditions specification of RT8008 DC/DC converter, where TJ (MAX) is the maximum junction temperature of the die (125°C) and TA is the maximum ambient temperature. The junction to ambient thermal resistance θ JA i s layout dependent. For SOT-23-5/TSOT-23-5 packages, the thermal resistance θJA is 250°C/W on the standard JEDEC 51-3 single-layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by following formula : PD(MAX) = ( 125°C - 25°C ) / 250 = 0.4 W for SOT-23-5/ TSOT-23-5 packages The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance θJA. For RT8008 packages, the Figure 5 of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. The value of junction to case thermal resistance θJC is popular for users. This thermal parameter is convenient for users to estimate the internal junction operated temperature of packages while IC operating. It's independent of PCB layout, the surroundings airflow effects and temperature difference between junction to ambient. The operated junction temperature can be calculated by following formula : TJ = TC + PD x θJC DS8008-04 March 2007 www.richtek.com 11 Where TC is the package case (Pin 2 of package leads) temperature measured by thermal sensor, PD is the power dissipation defined by user's function and the θJC is the junction to case thermal resistance provided by IC manufacturer. Therefore it's easy to estimate the junction temperature by any condition. Checking Transient Response The regulator loop response can be checked by looking at the load transient response. Switching regulators take several cycles to respond to a step in load current. When a load step occurs, VOUT immediately shifts by an amount equal to ∆ILOAD (ESR), where ESR is the effective series resistance of COUT . ∆ ILOAD also begins to charge or discharge COUT generating a feedback error signal used by the regulator to return VOUT to its steady-state value. During this recovery time, VOUT can be monitored for overshoot or ringing that would indicate a stability problem. 450 M axim um Pow er D issipatio n (m W) Single Layer PCB 400 350 300 250 200 150 100 50 0 0 20 40 60 80 100 120 140 SOT-23-5, TSOT-23-5 Packages Ambient Temperature (°C) Figure 5. Derating Curves for RT8008 Package Layout Considerations Follow the PCB layout guidelines for optimal performance of RT8008. } For the main current paths as indicated in bold lines in Figure 6, keep their traces short and wide. } Put the input capacitor as close as possible to the device pins (VIN and GND). } LX node is with high frequency voltage swing and should be kept small area. Keep analog components away from LX node to prevent stray capacitive noise pick-up. RT8008 } Connect feedback network behind the output capacitors. Keep the loop area small. Place the feedback components near the RT8008. } Connect all analog grounds to a command node and then connect the command node to the power ground behind the output capacitors. } An example of 2-layer PCB layout is shown in Figure 7 to Figure 8 for reference. VIN 4 RT8008 VIN LX 3 C1 1 EN FB GND VIN J1 5 2 C2 R1 C4 10uF L1 VOUT C3 R2 Figure 6. EVB Schematic Figure 7. Top Layer Figure 8. Bottom Layer Suggested Inductors Component Supplier TAIYO YUDEN TAIYO YUDEN Sumida Sumida GOTREND GOTREND Series NR 3015 NR 3015 CDRH2D14 CDRH2D14 GTSD32 GTSD32 Inductance (µH) 2.2 4.7 2.2 4.7 2.2 4.7 DCR (m Ω) 60 120 75 135 58 146 Current Rating (mA) 1480 1020 1500 1000 1500 1100 Dimensions (mm) 3 x 3 x 1.5 3 x 3 x 1.5 4.5 x 3.2 x 1.55 4.5 x 3.2 x 1.55 3.85 x 3.85 x 1.8 3.85 x 3.85 x 1.8 Suggested Capacitors for CIN and COUT Component Supplier TDK TDK M URATA M URATA M URATA TAIYO YUDEN TAIYO YUDEN TAIYO YUDEN Part No. C1608JB0J475M C2012JB0J106M GRM188R60J475KE19 GRM219R60J106ME19 GRM219R60J106KE19 JMK107BJ475RA JMK107BJ106MA JMK212BJ106RD Capacitance ( µF) 4.7 10 4.7 10 10 4.7 10 10 Case Size 0603 0805 0603 0805 0805 0603 0603 0805 www.richtek.com 12 DS8008-04 March 2007 RT8008 Outline Dimension H D L C B b A A1 e Symbol A A1 B b C D e H L Dimensions In Millimeters Min 0.889 0.000 1.397 0.356 2.591 2.692 0.838 0.080 0.300 Max 1.295 0.152 1.803 0.559 2.997 3.099 1.041 0.254 0.610 Dimensions In Inches Min 0.035 0.000 0.055 0.014 0.102 0.106 0.033 0.003 0.012 Max 0.051 0.006 0.071 0.022 0.118 0.122 0.041 0.010 0.024 SOT-23-5 Surface Mount Package DS8008-04 March 2007 www.richtek.com 13 RT8008 H D L C B b A A1 e Symbol A A1 B b C D e H L Dimensions In Millimeters Min 0.700 0.000 1.397 0.300 2.591 2.692 0.838 0.080 0.300 Max 1.000 0.100 1.803 0.559 3.000 3.099 1.041 0.254 0.610 Dimensions In Inches Min 0.028 0.000 0.055 0.012 0.102 0.106 0.033 0.003 0.012 Max 0.039 0.004 0.071 0.022 0.118 0.122 0.041 0.010 0.024 TSOT-23-5 Surface Mount Package Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Richtek Technology Corporation Taipei Office (Marketing) 8F, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com www.richtek.com 14 DS8008-04 March 2007