RT9166-18PVL

® RT9166/A 300/600mA, Ultra-Fast Transient Response LDO Regulator General Description Features The RT9166/A series are CMOS low dropout regulators optimized for ultra-fast transient response. The devices are capable of supplying 300mA or 600mA of output current with a dropout voltage of 230mV or 580mV respectively.  The RT9166/A series are is optimized for CD/DVD-ROM, CD/RW or wireless communication supply applications. The RT9166/A regulators are stable with output capacitors as low as 1μF. The other features include ultra low dropout voltage, high output accuracy, current limiting protection, and high ripple rejection ratio.          The devices are available in fixed output voltages range of 1.2V to 4.5V with 0.1V per step. The RT9166/A regulators are available in 3-lead SOT-23 (RT9166 only), SOT-89, SOT-223, TO-92 and TO-252 packages.  μA) Low Quiescent Current (Typically 220μ Guaranteed 300/600mA Output Current Low Dropout Voltage : 230/580mV at 300/600mA Wide Operating Voltage Ranges : 3V to 5.5V Ultra-Fast Transient Response Tight Load and Line Regulation Current Limiting Protection Thermal Shutdown Protection Only Low-ESR Ceramic Capacitor Required for Stability Custom Voltage Available RoHS Compliant and 100% Lead (Pb)-Free Applications  Ordering Information  RT9166/A-  CD/DVD-ROM, CD/RW Wireless LAN Card/Keyboard/Mouse Battery-Powered Equipment XDSL Router PCMCIA Card  Package Type VL : SOT-23-3 (L-Type) (RT9166 Only)  X : SOT-89 XL : SOT-89 (L-Type) Marking Information G : SOT-223 GL : SOT-223 (L-Type) For marking information, contact our sales representative Z : TO-92 directly or through a Richtek distributor located in your L : TO-252 area. Lead Plating System P : Pb Free Pin Configurations G : Green (Halogen Free and Pb Free) (TOP VIEW) Output Voltage 12 : 1.2V 13 : 1.3V : 45 : 4.5V 1B : 1.25V 600mA Output Current 300mA Output Current VIN 3 2 GND VOUT SOT-23-3 (L-Type) (RT9166) Note : Richtek products are :  RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020.  Suitable for use in SnPb or Pb-free soldering processes. Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 3 VOUT 2 GND 1 VIN TO-92 is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9166/A 1 3 1 VIN GND 2 2 3 1 2 1 1 2 3 GND VIN (TAB) VOUT 3 2 3 GND VOUT GND (TAB) SOT-89 VIN VOUT (TAB) VOUT GND (TAB) SOT-89 (L-Type) VIN SOT-223 SOT-223 (L-Type) VOUT VIN TO-252 Typical Application Circuit RT9166/A VIN VIN CIN VOUT COUT GND VOUT 1uF 1uF μF minimum X7R or X5R dielectric is strongly recommended if ceramics are Note: To prevent oscillation, a 1μ used as input/output capacitors. When using the Y5V dielectric, the minimum value of the input/output μF. (see Application capacitance that can be used for stable over full operating temperature range is 3.3μ Information Section for further details) Functional Pin Description Pin Name Pin Function VIN Supply Input. VOUT Regulator Output. GND Common Ground. Function Block Diagram VIN VOUT Thermal Shutdown Error Amplifier - + Current Limiting Sensor 1.2V Reference GND Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A Absolute Maximum Ratings        (Note 1) Supply Input Voltage ------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOT-23-3 --------------------------------------------------------------------------------------------------------------SOT-89 -----------------------------------------------------------------------------------------------------------------SOT-223 ---------------------------------------------------------------------------------------------------------------TO-92 -------------------------------------------------------------------------------------------------------------------TO-252 -----------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) SOT-23-3, θJA ---------------------------------------------------------------------------------------------------------SOT-89, θJA -----------------------------------------------------------------------------------------------------------SOT-89, θJC -----------------------------------------------------------------------------------------------------------SOT-223, θJA ----------------------------------------------------------------------------------------------------------SOT-223, θJC ---------------------------------------------------------------------------------------------------------TO-92, θJA -------------------------------------------------------------------------------------------------------------TO-92, θJC -------------------------------------------------------------------------------------------------------------TO-252, θJA -----------------------------------------------------------------------------------------------------------TO-252, θJC -----------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------Junction Temperature -----------------------------------------------------------------------------------------------Storage Temperature Range --------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Model) ----------------------------------------------------------------------------------------- Recommended Operating Conditions    6.5V 0.4W 0.571W 0.740W 0.625W 1.470W 250°C/W 175°C/W 58°C/W 135°C/W 15°C/W 160°C/W 40°C/W 68°C/W 7°C/W 260°C 150°C −65°C to 150°C 2kV (Note 4) Supply Input Voltage ------------------------------------------------------------------------------------------------- 2.8V to 5.5V Junction Temperature Range --------------------------------------------------------------------------------------- − 40°C to 125°C Ambient Temperature Range --------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VIN = VOUT + 1V or VIN = 2.8V whichever is greater, CIN = 1μF, COUT = 1μF, TA = 25° C, unless otherwise specified) Parameter Symbol Output Voltage Accuracy RT9166 Current Limit Quiescent Current RT9166A (Note 5) Dropout Voltage (Note 6) RT9166 RT9166A Load Regulation (Note 7) RT9166 RT9166A Typ Max Unit 1 -- 3 % 300 -- -- 600 -- -- IOUT = 1mA ILIM RLOAD = 1 IQ IOUT = 0mA -- 220 300 IOUT = 300mA -- 230 -- IOUT = 600mA -- 580 -- VIN = (VOUT + 0.3V) to 5.5V, IOUT = 1mA -- 0.2 -- 1mA  IOUT  300mA -- 15 35 1mA  IOUT  600mA -- 30 55 VDROP VLOAD Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 Min VOUT VLINE Line Regulation Test Conditions mA A mV %/V mV is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9166/A Parameter Symbol Test Conditions f = 1kHz, COUT = 1F Min Typ Max Unit -- 55 -- dB Power Supply Rejection Rate PSRR Thermal Shutdown Temperature TSD -- 170 -- C Thermal Shutdown Hysteresis TSD -- 40 -- C Note 1. Stresses beyond those listed “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and 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 may affect device reliability. Note 2. θJA is measured at TA = 25°C on a low effective thermal conductivity single-layer test board per JEDEC 51-3. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. Note 5. Quiescent, or ground current, is the difference between input and output currents. It is defined by IQ = IIN - IOUT under no load condition (IOUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground pin current. Note 6.The dropout voltage is defined as VIN − VOUT, which is measured when VOUT is VOUT(NORMAL) − 100mV. Note 7. Regulation is measured at constant junction temperature by using a 20ms current pulse. Devices are tested for load regulation in the load range from 1mA to 300mA and 600mA respectively. Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A Typical Operating Characteristics Power Supply Rejection Ratio Dropout Voltage vs. Load Current 700 CIN = 1uF COUT = 1uF 600 VIN = 5V CIN = 1uF COUT = 1uF TJ = 125°C -10 500 TJ = 25°C 400 300 TJ = −40°C 200 -20 PSRR (dB) Dropout Voltage (mV) 0 -30 100mA -40 1mA -50 100 0 -60 0 100 200 300 400 500 10 600 1k 10k Load Current (mA) Frequency (Hz) Region of Stable COUT ESR vs. Load Current Output Noise 100.00 Output Noise Signal (μV) 10.00 Instable 1.00 Stable 0.10 Instable 0.01 100k 1M ILOAD = 100mA COUT = 1uF VIN = 5V CIN = 1uF COUT = 1uF to 4.7uF COUT ESR (Ω) 100 400 200 0 -200 -400 f = 10Hz to 100KHz 0.00 0 100 200 300 400 500 Time (1ms/DIV) 600 Load Current (mA) Current Limit vs. Input voltage 900 850 850 Current Limit (mA) Current Limit (mA) Current Limit vs. Input voltage 900 800 VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω 750 800 750 VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω RT9166-33xX 700 700 3 3.5 4 4.5 5 Input voltage (V) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 5.5 3 3.5 RT9166-33xVL 4 4.5 5 5.5 Input voltage (V) is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9166/A Current Limit vs. Temperature 900 850 850 Current Limit (mA) Current Limit (mA) Current Limit vs. Temperature 900 800 VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω 750 800 750 RT9166-33xX 700 VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω RT9166-33xVL 700 -40 -50 -25 0 25 50 75 100 125 -50 -40 -25 0 Temperature (°C) 240 240 Quiescent Current (µA) 1 Quiescent Current (µA) 1 260 220 200 180 -25 0 25 50 180 160 VIN = 5V CIN = 1uF COUT = 1uF RT9166-33xVL 75 100 125 -50 -40 -25 0 25 50 75 Temperature Stability 3.35 3.35 Output Voltage (V) 3.40 3.30 3.25 3.30 3.25 VIN = 5V CIN = 1uF COUT = 1uF RT9166-33xX 3.20 RT9166-33xVL 3.20 -25 0 25 50 75 100 Temperature (°C) Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 125 Temperature Stability 3.40 -40 -50 100 Temperature (°C) Temperature (°C) VIN = 5V CIN = 1uF COUT = 1uF 125 200 140 -50 -40 100 220 RT9166-33xX 140 Output Voltage (V) 75 Quiescent Current vs. Temperature Quiescent Current vs. Temperature VIN = 5V CIN = 1uF COUT = 1uF 50 Temperature (°C) 260 160 25 125 -40 -50 -25 0 25 50 75 100 125 Temperature (°C) is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A VIN = 5V, ILOAD = 1 to 150mA CIN = COUT = 1uF (Ceramic, X7R) Load Current (mA) 200 100 0 20 0 -20 Load Transient Response RT9166-33xX Time (100μs/Div) Output Voltage Deviation (mV) Output Voltage Deviation (mV) Load Current (mA) Load Transient Response 200 VIN = 5V, ILOAD = 1 to 150mA CIN = COUT = 1uF (Ceramic, X7R) 100 0 20 0 -20 RT9166-33xVL Time (100μs/Div) Output Voltage Deviation (mV) Input Voltage Deviation (V) Line Transient Response 5 VIN = 4 to 5V CIN = 1uF COUT = 1uF 4 20 0 -20 Time (100μs/Div) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9166/A Application Information Like any low-dropout regulator, the RT9166/A series requires input and output decoupling capacitors. These capacitors must be correctly selected for good performance (see Capacitor Characteristics Section). Please note that linear regulators with a low dropout voltage have high internal loop gains which require care in guarding against oscillation caused by insufficient decoupling capacitance. Input Capacitor An input capacitance of ≅ 1μF is required between the device input pin and ground directly (the amount of the capacitance may be increased without limit). The input capacitor MUST be located less than 1 cm from the device to assure input stability (see PCB Layout Section). A lower ESR capacitor allows the use of less capacitance, while higher ESR type (like aluminum electrolytic) require more capacitance. Capacitor types (aluminum, ceramic and tantalum) can be mixed in parallel, but the total equivalent input capacitance/ESR must be defined as above to stable operation. There are no requirements for the ESR on the input capacitor, but tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance will be ≅ 1μF over the entire operating temperature range. Output Capacitor The RT9166/A is designed specifically to work with very small ceramic output capacitors. The recommended minimum capacitance (temperature characteristics X7R or X5R) is 1μF to 4.7μF range with 10mΩ to 50mΩ range ceramic capacitor between LDO output and GND for transient stability, but it may be increased without limit. Higher capacitance values help to improve transient. The output capacitor's ESR is critical because it forms a zero to provide phase lead which is required for loop stability. (When using the Y5V dielectric, the minimum value of the input/output capacitance that can be used for stable over full operating temperature range is 3.3μF.) Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 No Load Stability The device will remain stable and in regulation with no external load. This is specially important in CMOS RAM keep-alive applications. Input-Output (Dropout) Voltage A regulator's minimum input-to-output voltage differential (dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this determines the useful end-of-life battery voltage. Because the device uses a PMOS, its dropout voltage is a function of drain-tosource on-resistance, RDS(ON), multiplied by the load current : VDROPOUT = VIN − VOUT = RDS(ON) x IOUT Current Limit The RT9166/A monitors and controls the PMOS' gate voltage, minimum limiting the output current to 300mA for RT9166 and 600mA for RT9166A. The output can be shorted to ground for an indefinite period of time without damaging the part. Short-Circuit Protection The device is short circuit protected and in the event of a peak over-current condition, the short-circuit control loop will rapidly drive the output PMOS pass element off. Once the power pass element shuts down, the control loop will rapidly cycle the output on and off until the average power dissipation causes the thermal shutdown circuit to respond to servo the on/off cycling to a lower frequency. Please refer to the section on thermal information for power dissipation calculations. Capacitor Characteristics It is important to note that capacitance tolerance and variation with temperature must be taken into consideration when selecting a capacitor so that the minimum required amount of capacitance is provided over the full operating temperature range. In general, a good tantalum capacitor will show very little capacitance variation with temperature, but a ceramic may not be as good (depending on dielectric type). is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A Aluminum electrolytics also typically have large temperature variation of capacitance value. Equally important to consider is a capacitor's ESR change with temperature: this is not an issue with ceramics, as their ESR is extremely low. However, it is very important in Tantalum and aluminum electrolytic capacitors. Both show increasing ESR at colder temperatures, but the increase in aluminum electrolytic capacitors is so severe they may not be feasible for some applications. Ceramic : For values of capacitance in the 10μF to 100μF range, ceramics are usually larger and more costly than tantalums but give superior AC performance for by-passing high frequency noise because of very low ESR (typically less than 10mΩ). However, some dielectric types do not have good capacitance characteristics as a function of voltage and temperature. Z5U and Y5V dielectric ceramics have capacitance that drops severely with applied voltage. A typical Z5U or Y5V capacitor can lose 60% of its rated capacitance with half of the rated voltage applied to it. The Z5U and Y5V also exhibit a severe temperature effect, losing more than 50% of nominal capacitance at high and low limits of the temperature range. X7R and X5R dielectric ceramic capacitors are strongly recommended if ceramics are used, as they typically maintain a capacitance range within ±20% of nominal over full operating ratings of temperature and voltage. Of course, they are typically larger and more costly than Z5U/Y5U types for a given voltage and capacitance. Tantalum : Solid tantalum capacitors are recommended for use on the output because their typical ESR is very close to the ideal value required for loop compensation. They also work well as input capacitors if selected to meet the ESR requirements previously listed. Tantalums also have good temperature stability : a good quality tantalum will typically show a capacitance value that varies less than 10 to 15% across the full temperature range of 125°C to −40°C. ESR will vary only about 2X going from the high to low temperature limits. Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 The increasing ESR at lower temperatures can cause oscillations when marginal quality capacitors are used (if the ESR of the capacitor is near the upper limit of the stability range at room temperature). Aluminum : This capacitor type offers the most capacitance for the money. The disadvantages are that they are larger in physical size, not widely available in surface mount, and have poor AC performance (especially at higher frequencies) due to higher ESR and ESL. Compared by size, the ESR of an aluminum electrolytic is higher than either Tantalum or ceramic, and it also varies greatly with temperature. A typical aluminum electrolytic can exhibit an ESR increase of as much as 50X when going from 25°C down to −40°C. It should also be noted that many aluminum electrolytics only specify impedance at a frequency of 120Hz, which indicates they have poor high frequency performance. Only aluminum electrolytics that have an impedance specified at a higher frequency (between 20kHz and 100kHz) should be used for the device. Derating must be applied to the manufacturer's ESR specification, since it is typically only valid at room temperature. Any applications using aluminum electrolytics should be thoroughly tested at the lowest ambient operating temperature where ESR is maximum. Thermal Considerations Thermal protection limits power dissipation in RT9166/A. When the operation junction temperature exceeds 170°C, the OTP circuit starts the thermal shutdown function and turns the pass element off. The pass element turn on again after the junction temperature cools by 40°C. For continuous operation, do not exceed absolute maximum operation junction temperature. The power dissipation definition in device is : PD = (VIN − VOUT) x IOUT + VIN x IQ 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 is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9166/A PD (MAX) = (TJ(MAX) − TA) / θJA Where T J(MAX) is 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 condition specifications, the maximum junction temperature is 125°C. The junction to ambient thermal resistance θJA is layout dependent. For SOT-23-3 package, the thermal resistance θJA is 250°C/W on the standard JEDEC 51-3 single-layer thermal test board. For SOT-223 package, the thermal resistance θJA is 135°C/W on the standard JEDEC 51-3 single-layer thermal test board. For SOT-89 package, the thermal resistance θJA is 175°C/W on the standard JEDEC 51-3 single-layer thermal test board. For TO-92 package, the thermal resistance θJA is 160°C/W on the standard JEDEC 51-3 single-layer thermal test board. For TO-252 package, the thermal resistance θJA is 68°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 : 2.0 Maximum Power Dissipation (W)1 be calculated by following formula : Single Layer PCB 1.8 TO-252 1.6 1.4 1.2 1.0 SOT-223 0.8 TO-92 0.6 0.4 0.2 SOT-23-3 SOT-89 0.0 0 25 50 75 100 125 Ambient Temperature (°C) Figure 1. Derating Curve of Maximum Power Dissipation PD (MAX) = ( 125°C − 25°C) / 250°C/W = 0.400W for SOT-23-3 package PD (MAX) = ( 125°C − 25°C) / 175°C/W = 0.571W for SOT-89 package PD (MAX) = ( 125°C − 25°C) / 135°C/W = 0.740W for SOT-223 package PD (MAX) = ( 125°C − 25°C) / 160°C/W = 0.625W for TO-92 package PD (MAX) = ( 125°C − 25°C) / 68°C/W = 1.470W for TO-252 package The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance θJA. Figure 1 of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 10 is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A PCB Layout Good board layout practices must be used or instability can be induced because of ground loops and voltage drops. The input and output capacitors MUST be directly connected to the input, output, and ground pins of the device using traces which have no other currents flowing through them. The best way to do this is to layout CIN and COUT near the device with short traces to the VIN, VOUT, and ground pins. The regulator ground pin should be connected to the external circuit ground so that the regulator and its capacitors have a “single point ground”. It should be noted that stability problems have been seen in applications where “vias” to an internal ground plane were used at the ground points of the device and the input and output capacitors. This was caused by varying ground potentials at these nodes resulting from current flowing through the ground plane. Using a single point ground technique for the regulator and it’ s capacitors fixed the problem. Since high current flows through the traces going into VIN and coming from VOUT, Kelvin connect the capacitor leads to these pins so there is no voltage drop in series with the input and output capacitors. Optimum performance can only be achieved when the device is mounted on a PC board according to the diagram below : VIN GND VOUT Figure 2. SOT-23-3 Board Layout Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT9166/A Outline Dimension H D L C B e A A1 b Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 0.889 1.295 0.035 0.051 A1 0.000 0.152 0.000 0.006 B 1.397 1.803 0.055 0.071 b 0.356 0.508 0.014 0.020 C 2.591 2.997 0.102 0.118 D 2.692 3.099 0.106 0.122 e 1.803 2.007 0.071 0.079 H 0.080 0.254 0.003 0.010 L 0.300 0.610 0.012 0.024 SOT-23-3 Surface Mount Package Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A D D1 A B C C1 e e H A b b1 b Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 1.397 1.600 0.055 0.063 b 0.356 0.483 0.014 0.019 B 2.388 2.591 0.094 0.102 b1 0.406 0.533 0.016 0.021 C 3.937 4.242 0.155 0.167 C1 0.787 1.194 0.031 0.047 D 4.394 4.597 0.173 0.181 D1 1.397 1.753 0.055 0.069 e 1.448 1.549 0.057 0.061 H 0.356 0.432 0.014 0.017 3-Lead SOT-89 Surface Mount Package Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT9166/A Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 1.400 1.800 0.055 0.071 A1 0.020 0.100 0.001 0.004 b 0.600 0.840 0.024 0.033 B 3.300 3.700 0.130 0.146 C 6.700 7.300 0.264 0.287 D 6.300 6.700 0.248 0.264 b1 2.900 3.100 0.114 0.122 e 2.300 0.091 H 0.230 0.350 0.009 0.014 L 1.500 2.000 0.059 0.079 L1 0.800 1.100 0.031 0.043 3-Lead SOT-223 Surface Mount Package Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 14 is a registered trademark of Richtek Technology Corporation. DS9166/A-24 January 2016 RT9166/A D U C D1 R B T V E S L1 L3 b1 b L2 e b2 A Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 2.184 2.388 0.086 0.094 B 0.889 2.032 0.035 0.080 b 0.508 0.889 0.020 0.035 b1 1.016 Ref. 0.040 Ref. b2 0.457 0.584 0.018 0.023 C 0.457 0.584 0.018 0.023 D 6.350 6.731 0.250 0.265 D1 5.207 5.461 0.205 0.215 E 5.334 6.223 0.210 0.245 e 2.108 2.438 0.083 0.096 L1 9.398 10.414 0.370 0.410 L2 L3 0.508 Ref. 0.635 1.016 0.020 Ref. 0.025 0.040 U 3.810 Ref. 0.150 Ref. V 3.048 Ref. 0.120 Ref. R 0.200 0.850 0.008 0.033 S 2.500 3.400 0.098 0.134 T 0.500 0.850 0.020 0.033 3-Lead TO-252 Surface Mount Package Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9166/A-24 January 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 15 RT9166/A A D E L b e C D1 A1 Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 3.175 4.191 0.125 0.165 A1 1.143 1.372 0.045 0.054 b 0.406 0.533 0.016 0.021 C 0.406 0.533 0.016 0.021 D 4.445 5.207 0.175 0.205 D1 3.429 5.029 0.135 0.198 E 4.318 5.334 0.170 0.210 e 1.143 1.397 0.045 0.055 12.700 L 0.500 3-Lead TO-92 Plastic Package Richtek Technology Corporation 14F, No. 8, Tai Yuen 1st Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnished by Richtek is believed to be accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Richtek or its subsidiaries. www.richtek.com 16 DS9166/A-24 January 2016