RT9078-18GQZ

® RT9078 2μ μA IQ, 300mA Low-Dropout Linear Regulator General Description Features The RT9078 is a low-dropout (LDO) voltage regulators with enable function that operates from 1.2V to 5.5V. It provides up to 300mA of output current and offers low-power operation in miniaturized packaging.  The features of low quiescent current as low as 2μA and almost zero disable current is ideal for powering the battery equipment to a longer service life. The RT9078 is stable with the ceramic output capacitor over its wide input range from 1.2V to 5.5V and the entire range of output load current (0mA to 300mA). Pin Configuration          (TOP VIEW) VOUT SNS/NC 5 4 2    3 Applications VIN GND EN  TSOT-23-5  VOUT 2μ μA Ground Current at no Load PSRR = 75dB at 1kHz Adjustable Output Voltage Available by Specific Application ±2% Output Accuracy 300mA (VIN ≥ 1.7V) Output Current with EN Low (0.1μ μA) Disable Current 1.2V to 5.5V Operating Input Voltage Dropout Voltage : 0.15V at 300mA when VOUT ≥ 3V Support Fixed Output Voltage 0.8V, 1.0V, 1.05V, 1.1V, 1.2V, 1.25V, 1.3V, 1.5V, 1.8V, 1.85V, 2.5V, 2.8V, 2.85V, 3V, 3.1V, 3.3V, 3.45V Stable with Ceramic or Tantalum Capacitor Current Limit Protection Over Temperature Protection TSOT-23-5 and ZQFN-4L 1x1 (ZDFN-4L 1x1) Packages Available 1 4 VIN 3 EN  Portable, Battery Powered Equipment Ultra Low Power Microcontrollers Notebook Computers SGND GND 2 5 ZQFN-4L 1x1 (ZDFN-4L 1x1) Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9078 Ordering Information Marking Information RT9078/NPin 1 Orientation*** (2) : Quadrant 2, Follow EIA-481-D For marking information, contact our sales representative directly or through a Richtek distributor located in your area. Package Type J5 : TSOT-23-5 QZ : ZQFN-4L 1x1 (Z-Type) (ZDFN-4L 1x1) Lead Plating System G : Green (Halogen Free and Pb Free) Output Voltage 08 : 0.8V : 33 : 3.3V 1B : 1.25V 1H : 1.85V 2H : 2.85V 1K : 1.05V 3D : 3.45V (ZQFN-4L 1x1 only) Special Request : Any voltage between 0.8V and 3.3V under specific business agreement Pin Function RT9078 : Without SNS Pin RT9078N : With SNS Pin** Note : ***Empty means Pin1 orientation is Quadrant 1 Richtek products are : **Available for output target adjustment (Ex : RT9078N-08GJ5 with 0.8V reference level for output target adjustment)  RoHS compliant and compatible with the current require-  Suitable for use in SnPb or Pb-free soldering processes. ments of IPC/JEDEC J-STD-020. Functional Pin Description Pin No. TSOT-23-5 ZQFN-4L 1x1 (ZDFN-4L 1x1) Pin Name Pin Function 1 4 VIN Supply voltage input. 2 2 GND Ground. 3 3 EN Enable control input. 4 -- SNS Output voltage sense. (RT9078N only) NC No internal connection. 5 1 VOUT Output of the regulator. -- 5 (Exposed Pad) SGND Substrate of chip. Leave floating or tie to GND. Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Functional Block Diagram VIN (without sense function) Current/Thermal Sense GND SNS (with sense function) + - EN Bandgap Reference VOUT R1 EN R2 Operation Basic operation Current-Limit Protection The RT9078 is a low quiescent current linear regulator designed especially for low external components system. The input voltage range is from 1.2V to 5.5V. The RT9078 provides current limit function to prevent the device from damages during over-load or shorted-circuit condition. This current is detected by an internal sensing transistor. The minimum required output capacitance for stable operation is 1μF capacitance after consideration of the temperature and voltage coefficient of the capacitor. Output Transistor The RT9078 builds in a P-MOSFET output transistor which provides a low switch-on resistance for low dropout voltage applications. Over-Temperature Protection The over-temperature protection function will turn off the P-MOSFET when the junction temperature exceeds 150°C (typ.), and the output current exceeds 80mA. Once the junction temperature cools down by approximately 20°C, the regulator will automatically resume operation. Error Amplifier The Error Amplifier compares the internal reference voltage with the output feedback voltage from the internal divider, and controls the Gate voltage of P-MOSFET to support good line regulation and load regulation at output voltage. Enable The RT9078 delivers the output power when it is set to enable state. When it works in disable state, there is no output power and the operation quiescent current is almost zero. Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9078 Absolute Maximum Ratings         (Note 1) VIN, VOUT, SNS, EN to GND ------------------------------------------------------------------------------------------VOUT to VIN ---------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C TSOT-23-5 ------------------------------------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1) -------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) TSOT-23-5, θJA ------------------------------------------------------------------------------------------------------------TSOT-23-5, θJC ------------------------------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1), θJA -------------------------------------------------------------------------------------ZQFN-4L 1x1 (ZDFN-4L 1x1), θJC ------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Model) ---------------------------------------------------------------------------------------------- Recommended Operating Conditions    −0.3V to 6.5V −6.5V to 0.3V 0.43W 0.44W 230.6°C/W 21.8°C/W 226°C/W 43°C/W 260°C 150°C −65°C to 150°C 2kV (Note 4) Input Voltage, VIN --------------------------------------------------------------------------------------------------------- 1.2V to 5.5V Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VOUT + 1 < VIN < 5.5V, TA = 25°C, unless otherwise specified) Parameter Fixed Output Voltage Range Symbol Min Typ Max Unit 0.8 -- 3.45 V ILOAD = 1mA 2 -- 2 % ILOAD = 1mA 0.784 0.8 0.816 V 0.8V  VOUT  1.05V -- 0.7 0.97 1.05V  VOUT  1.2V -- 0.5 0.92 1.2V  VOUT  1.5V -- 0.4 0.57 1.5V  VOUT  1.8V -- 0.3 0.47 1.8V  VOUT  2.1V -- 0.24 0.33 2.1V  VOUT  2.5V -- 0.21 0.3 2.5V  VOUT  2.8V -- 0.18 0.25 2.8V  VOUT  3V -- 0.16 0.23 3V  VOUT -- 0.15 0.2 VDROP 1.8V  VOUT  2.1V -- 0.16 0.2 V IQ ILOAD = 0mA, VOUT  5.5V VIN  VOUT + VDROP -- 2 4 A VOUT DC Output Accuracy SNS Reference Voltage (for RT9078N-08GJ5 only) Dropout Voltage (ILOAD = 300mA) Dropout Voltage (ILOAD = 200mA) (Note 5) (Note 5) VCC Consumption Current Test Conditions VREF VDROP Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 V is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Parameter Symbol Test Conditions Min Typ Max Unit Shutdown GND Current (Note 6) VEN = 0V -- 0.1 0.5 A Shutdown Leakage Current (Note 6) VEN = 0V, VOUT = 0V -- 0.1 0.5 A VEN = 5.5V -- -- 0.1 A 1.2V  VIN  1.5V -- 0.3 0.6 1.5V  VIN  1.8V -- 0.15 0.3 1.8V  VIN  5.5V -- 0.13 0.35 EN Input Current IEN LINE Line Regulation ILOAD = 1mA % Load Regulation LOAD 1mA < ILOAD < 300mA -- 0.5 1 % Power Supply Rejection Ratio PSRR VIN = 3V, ILOAD = 50mA, COUT = 1F, VOUT = 2.5V, f = 1kHz -- 75 -- dB VOUT = 0.8V -- 38 -- VOUT = 1.2V -- 46 -- VOUT = 1.8V -- 48 -- VOUT = 3.3V -- 51 -- COUT = 1F, ILOAD = 150mA, BW = 10Hz to 100kHz, VIN = VOUT + 1V Output Voltage Noise Output Current Limit VRMS ILIM VOUT = 90%VOUT(Normal) 350 600 -- Logic-High VIH VIN = 5V 0.9 -- -- Logic-Low VIL VIN = 5V -- -- 0.4 Thermal Shutdown Temperature TSD ILOAD = 30mA, VIN  1.5V -- 150 -- C Thermal Shutdown Hysteresis TSD -- 20 -- C -- 80 --  Enable Input Voltage Discharge Resistance EN = 0V, VOUT = 0.1V mA V 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 in the natural convection at TA = 25°C on a two-layer Richtek Evaluation Board for ZQFN-4L 1x1 (ZDFN4L1x1) Package. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7 for TSOT-235 Package. 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. The dropout voltage is defined as VIN − VOUT, when VOUT is 98% of the normal value of VOUT. For the application under following condition : 1.8V ≤ VOUT < 2.1V, ILOAD = 200mA, TA = 85°C, the maximum dropout voltage is guaranteed by design that not over 0.28V. Note 6. The specification is tested at wafer stage and guarantee by design after assembly. Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9078 Typical Application Circuit RT9078N VIN CIN 1µF EN VIN VOUT VOUT COUT (Capacitance  1µF) SNS EN GND Figure 1. Application with Sense Function RT9078 VIN CIN 1µF EN VIN VOUT VOUT COUT (Capacitance  1µF) EN GND Figure 2. Application without Sense Function RT9078N VIN CIN 1µF VIN VOUT VOUT R1 SNS EN EN NC COUT (Capacitance  1µF) R2 GND Figure 3. Adjustable Output Voltage Application Circuit Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Typical Operating Characteristics Output Voltage vs. Temperature 3.40 0.88 3.38 0.86 3.36 Output Voltage (V) Output Voltage (V) Output Voltage vs. Temperature 0.90 0.84 0.82 0.80 VIN = 1.2V VIN = 2.1V VIN = 5.5V 0.78 0.76 0.74 3.34 3.32 VIN = 3.8V VIN = 4.5V VIN = 5.5V 3.30 3.28 3.26 3.24 0.72 3.22 VOUT = 0.8V, ILOAD = 1mA 0.70 VOUT = 3.3V, ILOAD = 1mA 3.20 -50 -25 0 25 50 75 100 125 -50 -25 Temperature (°C) 50 75 100 125 Output Voltage vs. Load Current 0.88 1.00 0.86 0.95 0.90 0.84 Output Voltage (V) Output Voltage (V) 25 Temperature (°C) Output Voltage vs. Input Voltage 0.82 0.80 0.78 0.76 0.85 0.80 VIN = 3V VIN = 5V 0.75 0.70 0.65 0.60 0.74 0.55 VOUT = 0.8V, ILOAD = 1mA 0.72 ILOAD = 0mA to 300mA 0.50 1.2 1.7 2.2 2.7 3.2 3.7 4.2 4.7 5.2 5.7 0 50 0.35 100 150 200 Ground Current vs. Load Current 0.35 300 Ground Current vs. Load Current 0.30 GND Current (mA) 0.30 0.25 0.20 0.15 TA = 85°C TA = 25°C TA = −40°C 0.10 0.05 0.25 0.20 TA = −40°C TA = 25°C TA = 125°C 0.15 0.10 0.05 VOUT = 3V VOUT = 0.8V 0.00 0.001 250 Load Current (mA) Input Voltage (V) GND Current (mA) 0 0.01 0.1 1 10 100 Load Current (mA) Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 1000 0.00 0.001 0.01 0.1 1 10 100 1000 Load Current (mA) is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9078 Shutdown Leakage Current vs. Temperature Shutdown Current vs. Input Voltage 0.10 VOUT = 0.8V, EN = 0V Shutdown Leakage Current (μA)1 Shutdown Current (μA)1 0.1 0.08 0.06 0.04 0.02 0 VOUT = 0.8V, EN = 0V 0.08 0.06 0.04 VIN = 1.8V VIN = 5.5V 0.02 0.00 1 2 3 4 5 6 -50 -25 0 Input Voltage (V) EN Threshold vs. Input Voltage Enable High 125 Enable High 0.6 Enable Low EN Threshold (V) EN Threshold (V) 100 0.67 0.5 0.4 0.3 0.2 0.66 0.65 0.64 0.62 0 0.61 2 3 4 5 Enable Low 0.63 0.1 1 VIN = 5.5V -50 6 -25 0 Input Voltage (V) ILOAD = 300mA Current Limit (mA) 0.16 ILOAD = 200mA 0.12 0.10 0.08 ILOAD = 100mA 0.06 0.04 100 125 VOUT = 0.8V VOUT = 3.3V 500 400 300 200 100 ILOAD = 10mA 0.02 75 600 0.18 0.14 50 Current Limit vs. Temperature 700 VOUT = 2.85V 25 Temperature (°C) Dropout Voltage vs. Temperature Dropout Voltage (V) 75 EN Threshold vs. Temperature 0.7 0.20 50 0.68 0.8 0.22 25 Temperature (°C) VIN = 5V 0.00 0 -50 -25 0 25 50 75 100 Temperature (°C) Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 125 -50 -25 0 25 50 75 100 125 Temperature (°C ) is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Fold-Back Current Limit vs. Temperature SNS Input Current vs. Temperature 350 0.9 0.8 SNS Input Current (μA) Fold-Back Current Limit (mA) VOUT = 0.8V 300 250 VOUT = 3.3V 200 150 100 50 VIN = 5V 0 0.7 0.6 0.5 0.4 0.3 0.2 0.1 VIN = 5V, VOUT = 0.8V, EN = H 0.0 -50 -25 0 25 50 75 100 125 -50 25 50 75 Temperature (°C) Power On from EN Power Off from EN EN (2V/Div) VOUT (2V/Div) VOUT (2V/Div) VIN = 3.8V, VOUT = 2.8V, ILOAD = 300mA I LOAD (200mA/Div) 100 125 VIN = 3.8V, VOUT = 2.8V, ILOAD = 300mA Time (250μs/Div) Time (500μs/Div) Line Transient Load Transient VIN = 3.8V, VOUT = 1.8V, ILOAD = 1mA to 300mA VIN = 2.8V to 3.8V, VOUT = 1.8V, ILOAD = 1mA I LOAD (0.1A/Div) VIN (1V/Div) VOUT (10mV/Div) VOUT (2mV/Div) Time (250μs/Div) Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 0 Temperature (°C ) EN (2V/Div) I LOAD (200mA/Div) -25 Time (100μs/Div) is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9078 PSRR vs. Frequency 0 -20 -20 ILOAD = 50mA ILOAD = 30mA ILOAD = 15mA ILOAD = 10mA -40 PSRR (dB) PSRR (dB) PSRR vs. Frequency 0 -60 -80 -40 ILOAD = 150mA ILOAD = 50mA ILOAD = 15mA -60 -80 VIN = 2.8V, VOUT = 0.8V, COUT = 1μF VIN = 3.3V, VOUT = 2.8V, COUT = 1μF -100 -100 10 100 1000 10000 100000 1000000 10 100 1000 100000 1000000 Frequency (Hz) Frequency (Hz) Output Noise Output Noise 500 500 400 400 300 300 200 200 Noise (μV) Noise (μV) 10000 100 0 -100 -200 100 0 -100 -200 -300 -300 VIN = 2.5V, VOUT = 0.8V, ILOAD = 300mA, COUT = 1μF, Frequency = 10Hz to 100kHz -400 -500 VIN = 4.5V, VOUT = 3.3V, ILOAD = 300mA, COUT = 1μF, Frequency = 10Hz to 100kHz -400 -500 0 1 2 3 4 5 6 7 8 Sec (m) Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 10 9 10 0 1 2 3 4 5 6 7 8 9 10 Sec (m) is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Application Information Enable The RT9078 has an EN pin to turn on or turn off the regulator, When the EN pin is in logic high, the regulator will be turned on. The shutdown current is almost 0μA typical. The EN pin may be directly tied to VIN to keep the part on. The Enable input is CMOS logic and cannot be left floating. Adjustable Output Voltage Setting Because of the small input current at the SNS pin, the RT9078N with SNS pin also can work as an adjustable output voltage LDO. Figure 3 gives the connections for the adjustable output voltage application. The resistor divider from VOUT to SNS sets the output voltage when in regulation. The voltage on the SNS pin sets the output voltage and is determined by the values of R1 and R2. In order to keep a good temperature coefficient of output voltage, the values of R1 and R2 should be selected carefully to ignore the temperature coefficient of input current at the SNS pin. A current greater than 50μA in the resistor divider is recommended to meet the above requirement. The adjustable output voltage can be calculated using the formula given in equation 1 : VOUT  R1 + R2  VSNS (1) R2 where VSNS is determined by the output voltage selections in the ordering information of the RT9078N. The maximum adjustable output voltage can be as high as input voltage deducted by the dropout voltage. When we choose 51kΩ and 16kΩ as R1 and R2 respectively, and select a 0.8V output at SNS pin, the Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 adjustable output voltage will be set to around 3.35V. Its temperature coefficient in Figure 4 is still perfect in such kind of application. Output Voltage vs. Temperature 3.35 3.34 Output Voltage (V) Like any low dropout linear regulator, the RT9078’s external input and output capacitors must be properly selected for stability and performance. Use a 1μF or larger input capacitor and place it close to the IC's VIN and GND pins. Any output capacitor meeting the minimum 1mΩ ESR (Equivalent Series Resistance) and capacitance larger than 1μF requirement may be used. Place the output capacitor close to the IC's VOUT and GND pins. Increasing capacitance and decreasing ESR can improve the circuit's PSRR and line transient response. 3.33 3.32 3.31 3.30 3.29 ILOAD = 1mA 3.28 -50 -25 0 25 50 75 100 125 Temperature (°C) Figure 4. Temperature Coefficient of Adjustable Output Voltage The minimum recommended 50μA in the resistor divider makes the application no longer an ultra low quiescent LDO. Figure 5 is another fine adjustable output voltage application can keep the LDO still operating in low power consumption. The fine tune range is recommended to be less than 50mV (R1 ≤ 91kΩ) in order to keep a good temperature coefficient of the output voltage. RT9078N VIN VOUT 1µF R1 SNS 56pF/NC 1µF EN GND Figure 5. Fine Adjustable Output Voltage Application Circuit There isn't extra current consumption in the above application. But the temperature coefficient of output voltage will be degraded by the input current at SNS pin. If the tuning range is larger than 50mV, a compensation capacitor (56pF) is required to keep the stability of output voltage. The fine adjustable output voltage is calculated using the formula given in equation 2 : is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT9078 (2) where ISNS is the input Current at SNS pin (typical 550nA at room temperature) and VSNS is determined by the output voltage selections in the ordering information of the RT9078N. Current Limit The RT9078 contains an independent current limiter, which monitors and controls the pass transistor's gate voltage, limiting the output current to 0.6A (typ.). The current limiting level is reduced to around 0.3A named fold-back current limit when the output voltage is further decreased. The output can be shorted to ground indefinitely without damaging the part. ambient temperature for fixed T J(MAX) and thermal resistance, θJA. The derating curve in Figure 6 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. 0.6 Maximum Power Dissipation (W)1 VOUT  VSNS + ISNS  R1 Four-Layer PCB for TSOT-23-5 package Two-Layer Richtek EVB for ZQFN (ZDFN)-4L 1x1 package 0.5 0.4 0.3 ZQFN-4L 1x1 (ZDFN-4L 1x1) 0.2 TSOT-23-5 0.1 0.0 Thermal Considerations For continuous operation, do not exceed absolute maximum junction temperature. The maximum power dissipation depends on the thermal resistance of the IC package, PCB layout, rate of surrounding airflow, and difference between junction and ambient temperature. The maximum power dissipation can be calculated by the following formula : PD(MAX) = (TJ(MAX) − TA) / θJA where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θJA is the junction to ambient thermal resistance. For recommended operating condition specifications the maximum junction temperature is 125°C and TA is the ambient temperature. The junction to ambient thermal resistance, θJA, is layout dependent. For TSOT-23-5 package, the thermal resistance, θJA, is 230.6°C/W on a standard JEDEC 51-7 four-layer thermal test board. For ZQFN-4L 1x1 (ZDFN-4L 1x1) package, the thermal resistance, θJA, is 226°C/W on a two-layer Richtek evaluation board. The maximum power dissipation at TA = 25°C can be calculated by the following formula : 0 25 50 75 100 125 Ambient Temperature (°C) Figure 6. Derating Curve of Maximum Power Dissipation Layout Consideration For best performance of the RT9078, the PCB layout suggestions below are highly recommend. All circuit components placed on the same side and as near to the respective LDO pin as possible, place the ground return path connection to the input and output capacitor. Using vias and long power traces for the input and output capacitors connection is discouraged and have negatively affects on performance. Figure 7 and Figure 8 shows the examples for the layout reference that reduce conduction trace loop, helping inductive parasitic minimize, load transient reduction and good circuit stability. PD(MAX) = (125°C − 25°C) / (230.6°C/W) = 0.43W for TSOT-23-5 package PD(MAX) = (125°C − 25°C) / (226°C/W) = 0.44W for ZQFN-4L 1x1 (ZDFN-4L 1x1) package The maximum power dissipation depends on the operating Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 Ground Power Plane VOUT 1 4 VIN 3 EN SGND GND 5 2 Place input/output capacitors as close as possible to the connecting pins for minimize power loop area and low impedance connection to GND plate. Connected with enable source by via Figure 7. PCB Layout Guide for ZQFN-4L 1x1 package Place input/output capacitors as close as possible to the connecting pins for minimize power loop area and low impedance connection to GND plate. Resistive divider is for output voltage adjustment (RT9078N package only). R1 R2 VOUT SNS/NC 5 4 Ground Power Plane 2 Thermal vias helps to reduce power trace and improve thermal dissipation 3 VIN GND EN Enable source Figure 8. PCB Layout Guide for TSOT-23-5 package Copyright © 2018 Richtek Technology Corporation. All rights reserved. DS9078-13 April 2018 is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT9078 Outline Dimension H D L B C b A A1 e Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.700 1.000 0.028 0.039 A1 0.000 0.100 0.000 0.004 B 1.397 1.803 0.055 0.071 b 0.300 0.559 0.012 0.022 C 2.591 3.000 0.102 0.118 D 2.692 3.099 0.106 0.122 e 0.838 1.041 0.033 0.041 H 0.080 0.254 0.003 0.010 L 0.300 0.610 0.012 0.024 TSOT-23-5 Surface Mount Package Copyright © 2018 Richtek Technology Corporation. All rights reserved. www.richtek.com 14 is a registered trademark of Richtek Technology Corporation. DS9078-13 April 2018 RT9078 1 1 2 2 DETAIL A Pin #1 ID and Tie Bar Mark Options Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.300 0.400 0.012 0.016 A1 0.000 0.050 0.000 0.002 A3 0.117 0.162 0.005 0.006 b 0.175 0.275 0.007 0.011 D 0.900 1.100 0.035 0.043 D2 0.450 0.550 0.018 0.022 E 0.900 1.100 0.035 0.043 E2 0.450 0.550 0.018 0.022 e L 0.625 0.200 0.025 0.300 0.008 0.012 H 0.039 0.002 H1 0.064 0.003 Z-Type 4L QFN 1x1 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. 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. DS9078-13 April 2018 www.richtek.com 15