® RT9074 60V, 30μ μA IQ, Low Dropout Voltage Linear Regulator General Description Features The RT9074 family are high voltage (60V operation), low quiescent current low dropout linear regulators capable of supplying 100mA of output current with a maximum dropout voltage of 400mV. The low quiescent and shutdown currents (30μA operating and 2μA shutdown) are ideal for use in battery-powered and/or high voltage systems. Ground current is well-controlled in all conditions, including dropout. The RT9074 family operates with any reasonable output capacitors including 1μF low-ESR ceramic types and features excellent line and load transient responses. Internal protection circuitry includes reverse-battery protection, current limiting, thermal shutdown, and reverse current protection. Output voltage accuracy is ±3% over the entire line and load range. Wide Input Voltage Range : 4.5V to 60V μA Low Quiescent Current : 30μ μA Operating and 2μ Shutdown Low Dropout Voltage : 400mV maximum at 100mA Fixed (2.5V, 3.3V, 5V) and adjustable (1.25V to 60V) versions ±3% Output Tolerance Over Line and Load Stable with 1μ μF Output Capacitor (Aluminum, Tantalum or Ceramic) Inherent Reverse-Current Protection (No diode needed) −60V Reverse-Battery Protection Applications These devices are available in 3 fixed-output versions (2.5V, 3.3V, 5V) as well as a version that supports an adjustable output voltage (1.25V to 60V). All versions come in SOP-8 package with an exposed pad for high power dissipation. The fixed output versions are also available packaged in SOT-223. Low Current, High Voltage Regulators Battery Powered Applications Telecom and Datacom Applications Automotive Application Typical Application Circuit VOUT 2.5V/3.3V/5V VIN 4.5V to 60V VIN 4.5V to 60V RT9074 CIN 0.18µF VIN SHDN COUT 1µF CIN 0.18µF VIN SENSE GND RT9074-25/33/50 GND R1 COUT 1µF FB R2 RT9074 (Adjustable Up to 25V Output) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 RT9074 VOUT SHDN VOUT 1.25V to 60V VIN 4.5V to 60V RT9074 VOUT SENSE VOUT 1.25V to 25V CIN 0.18µF VIN VOUT SENSE SHDN GND CCOMP R1 FB COUT 1µF R2 RT9074 (Adjustable Up to 60V Output) is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9074 Ordering and Marking Information Part No. RT907425GG RT907425GSP RT907433GG RT907433GSP RT907450GG RT907450GSP RT9074 GSP Output Voltage Package Pin Configurations Marking Information SOT-223 RT907425GG SOP-8 RT907425GSP SOT-223 RT907433GG SOP-8 RT907433GSP SOT-223 RT907450GG SOP-8 RT907450GSP (TOP VIEW) GND 2.5V 1 3 3.3V GND VOUT (TAB) VIN RT9074-25/33/50 SOT-223 5V VOUT Adjustable SOP-8 RT9074GSP Note : RoHS compliant and compatible with the current require- VIN 8 SENSE 2 NC 3 NC 4 Richtek products are : 2 GND 9 7 GND 6 GND 5 SHDN RT9074-25/33/50 SOP-8 ( Exposed Pad) ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. VOUT 8 SENSE 2 FB 3 NC 4 GND 9 VIN 7 GND 6 GND 5 SHDN RT9074 SOP-8 ( Exposed Pad) Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 Pin Description Pin No. Name RT9074RT9074GSP RT9074GG 25/33/50GSP 1 1 3 Function VOUT VOUT supplies power to the load. A minimum output capacitor of 1F is required for stable operation. Output Voltage Sense. For applications with VOUT 25V, SENSE can be connected to the output voltage to optimize the control loop compensation. For applications with VOUT > 25V (adjustable versions only), SENSE must be left unconnected. Control loop compensation is optimized by adding a feed-forward capacitor in the feedback resistor divider connected to FB (see Adjustable Output Voltage and Compensation section). 2 2 -- SENSE 3 -- -- NC -- 3 -- FB 4 -- -- NC No Internal Connection. Feedback Input. Connect to the center tap of a resistor divider for setting the output voltage. (Adjustable versions only) No Internal Connection. 5 5 -- SHDN Shutdown Control Input (Active High). Connect SHDN high to disable the output voltage and reduce the IC’s quiescent current to 2A (typical). Connect SHDN low to enable the output. SHDN is a high-voltage input (also able to withstand reverse voltage) and can be connected directly to a high-voltage input. 6, 7, 9* 6, 7, 9* 2 GND Ground. The exposed pad should be soldered to a large PCB and connected to GND for maximum thermal dissipation. 8 8 1 VIN Power Input. Bypass VIN with a 0.18F or larger capacitor with adequate voltage rating. * exposed pad Function Block Diagram VOUT VIN Current Limit Error Amp VOUT VIN Current Limit Error Amp SHDN SHDN OverTemperature Protection SENSE - + + - OverTemperature Protection SENSE FB Reference Reference GND RT9074-25/33/50 (Fixed Output) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 GND RT9074 (Adjustable Output) is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9074 Operation The RT9074 is a high input-voltage linear regulator specifically designed to minimize external components. The input voltage range is from 4.5V to 60V. The device supplies 100mA of output current with a maximum dropout voltage of 400mV. Its 30μA quiescent and 2μA shutdown currents make it ideal for use in battery-powered applications. Unlike many PNP LDO regulators, ground current does not increase much in dropout conditions. Output Transistor The RT9074 includes a built-in PNP output transistor configured for low dropout voltage. The output transistor blocks reverse current if the output voltage is held higher than the input voltage (such as in battery-backup applications) so no additional output blocking diode is needed. Over-Temperature Protection The over temperature protection function will turn off the PNP output transistor when the internal junction temperature exceeds 155°C (typ.). Once the junction temperature cools down by approximately 5°C, the regulator will automatically resume operation. Reverse-Battery Protection The RT9074 inputs (VIN and SHDN) can withstand reverse voltages as high as −60V. Both the IC and the load are protected, as long as the load impedance is 500Ω or less. In these conditions, the output voltage is guaranteed to be no more negative than −1V with the maximum negative input voltage. In battery-powered applications, no additional protection against battery reversal is typically needed. Error Amplifier Reverse-Output Protection The Error Amplifier compares the output feedback voltage from an internal feedback voltage divider (fixed output versions) or FB (adjustable output versions) to an internal reference voltage and controls the PNP output transistor's base current to maintain output voltage regulation. The RT9074's internal dividers are placed between SENSE and GND and have a divider resistance of about 1MΩ. The RT9074 protects against current flow to the input (VIN) when the output voltage exceeds VIN. This simplifies battery and capacitive “keep-alive” circuits since they need no additional output blocking diode. Current Limit Protection The RT9074 provides a current limit function to prevent damage during output over-load or shorted-circuit conditions. The output current is detected by an internal current-sense transistor. Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 Shutdown Input (8 Pin Versions) The RT9074 SHDN input is an active-high input that turns off the output transistor and reduces the quiescent current to 2μA typical. Connect SHDN to a voltage below 0.6V for normal operation. is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 Absolute Maximum Ratings (Note 1) VIN to GND ------------------------------------------------------------------------------------------------------------------ −60V to 80V SHDN to GND --------------------------------------------------------------------------------------------------------------- −60V to 80V VOUT to GND --------------------------------------------------------------------------------------------------------------- −40V to 80V SENSE to GND ------------------------------------------------------------------------------------------------------------- −30V to 35V VIN to VOUT/SENSE when |VIN| ≥ |VOUT| (Normal Operation or Reverse-Battery Condition) -------- −60V to 80V VIN to VOUT/SENSE when VOUT ≥ VIN ≥ 0 (Reverse-VOUT Condition) ------------------------------------ −35V FB ------------------------------------------------------------------------------------------------------------------------------ −0.3V to 10V FB Current ------------------------------------------------------------------------------------------------------------------- −6mA to 6mA Power Dissipation, PD @ TA = 25°C SOT-223 ---------------------------------------------------------------------------------------------------------------------- 1.25W SOP-8 ( Exposed Pad) ----------------------------------------------------------------------------------------------------------------- 3.26W Package Thermal Resistance (Note 2) SOT-223, θJA ----------------------------------------------------------------------------------------------------------------- 80°C/W SOP-8 ( Exposed Pad), θJA ------------------------------------------------------------------------------------------------ 30.6°C/W SOT-223, θJC ---------------------------------------------------------------------------------------------------------------- 7.4°C/W SOP-8 ( Exposed Pad), θJC ----------------------------------------------------------------------------------------------- 3.4°C/W Junction Temperature ------------------------------------------------------------------------------------------------------ 150°C Lead Temperature (Soldering, 10 sec.) -------------------------------------------------------------------------------- 260°C Storage Temperature Range --------------------------------------------------------------------------------------------- −65°C to 150°C ESD Susceptibility (Note 3) HBM (Human Body Model) ----------------------------------------------------------------------------------------------- 2kV Recommended Operating Conditions (Note 4) Supply Input Voltage ------------------------------------------------------------------------------------------------------- 4.5V to 60V Junction Temperature Range --------------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range --------------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (4.5V < VIN < 60V, VSHDN = 0V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit 4.5 -- 60 V Input Supply Operational VIN VIN 0 < IOUT < 100mA Quiescent Current IQ VIN = 24V, VSHDN = 0V -- 30 40 A Shutdown Current ISHDN VIN = 24V, VSHDN = 2.5V, VOUT = 0 -- 2 15 A Input Reverse Leakage Current IVINr VIN = 60V, VOUT = 0V -- -- 0.1 mA 120 -- 300 mA Output Voltage and Current Output Current Limit ILIM Line Regulation VLINE 5.5V < VIN < 60V, IOUT = 100mA -- 1.2 -- % Load Regulation VLOAD 0.1mA < IOUT < 100mA -- 1.2 -- % Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9074 Parameter Min Typ Max Unit 0 < IOUT < 100mA 1.225 1.25 1.275 V 0 < IOUT < 100mA 2.425 2.5 2.575 0 < IOUT < 100mA 3.2 3.3 3.4 5.4V < VIN < 60V, 0 < IOUT < 100mA 4.85 5 5.15 -- 20 50 nA VIN = 60V, RL = 500 -- -- 1 V IOUT = 1mA -- 15 80 IOUT = 10mA -- 55 150 IOUT = 100mA -- 240 400 Power Supply Rejection Rate PSRR f = 1kHz, IOUT = 50mA -- 60 -- dB Output Noise Voltage VON IOUT = 50mA, f = 10Hz to 100kHz -- 200 -- VRMS Shutdown Output Voltage VOUTSD SHDN = VIN -- -- 100 mV SHDN High Threshold VIH -- 1.6 2.2 V SHDN Low Threshold VIL 0.6 1.2 -- V SHDN Input Bias Current ISHDN SHDN = VIN -- 0.6 1.2 VSHDN = 0V -- -- 0.1 145 155 165 FB Voltage RT9074 Symbol VFB RT9074-25 Output Voltage RT9074-33 VOUT RT9074-50 FB Input Bias Current RT9074 IFB Output Voltage with Reverse VROUT Polarity VIN Dropout Voltage Test Conditions VDROP V mV Shutdown A Thermal Protection Thermal Shutdown TSD 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 high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is measured at the exposed pad of the package. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 Typical Operating Characteristics (TA = 25°C, CIN = 0.18μF, COUT = 1μF, unless otherwise specified) Output Voltage vs. Output Current Quiescent Current vs. Input Voltage 35 Quiescent Current (μA) 0.0 Output Voltage (%) 1 -0.2 -0.4 -0.6 -0.8 30 SHDN_Low 25 20 15 10 SHDN_High 5 VIN = 4.5V to 60V VIN = 14V 0 -1.0 0 20 40 60 80 0 100 10 20 Output Current (mA) Output Voltage vs. Temperature 45 50 60 VIN = 14V Quiescent Current (μA) 40 3.35 Output Voltage (V) 40 Quiescent Current vs. Temperature 3.40 IOUT = 1mA 3.30 IOUT = 10mA 3.25 3.20 3.15 35 30 SHDN_Low 25 20 15 10 SHDN_High 5 VIN = 14V 3.10 0 -50 -25 0 25 50 75 100 125 -50 -25 0 SHDN Threshold Voltage (V) -20 COUT = 1μF -30 -40 -50 COUT = 10μF -70 IOUT = 50mA -80 10 100 1000 10000 100000 Frequency (Hz) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 75 100 125 2.5 -10 -60 50 SHDN Threshold Voltage vs. Temperature PSRR 0 25 Temperature (°C) Temperature (°C) PSRR/dB 30 Input Voltage (V) 1000000 2.0 VIH 1.5 VIL 1.0 0.5 VIN = 14V 0.0 -50 -25 0 25 50 75 100 125 150 Temperature (°C) is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9074 Output Voltage vs. Input Voltage Current Limit vs. Input Voltage 1.0 210 0.8 TA = 125°C 190 Output Voltage (%) Current Limit (mA) 0.6 170 TA = −40°C 150 130 110 0.4 0.2 0.0 IOUT = 0mA IOUT = 50mA IOUT = 80mA IOUT = 100mA -0.2 -0.4 -0.6 90 -0.8 -1.0 70 0 10 20 30 40 50 0 60 10 20 Leakage Current (mA)1 Ground Current (mA) 7.0 6.0 5.0 In Dropout 4.0 3.0 2V Dropout 2.0 1.0 0.25 0.20 0.15 0.10 0.05 0.00 0 20 40 60 80 100 -80 Output Current (mA) -60 -50 -40 -30 -20 -10 0 Output Noise vs. Frequency 200 IOUT = 40mA IOUT = 50mA IOUT = 80mA IOUT = 100mA 180 Output Noise (µV) IOUT = 0mA IOUT = 1mA IOUT = 10mA IOUT = 20mA IOUT = 30mA -70 Reverse Voltage (V) Dropout Voltage vs. Temperature Dropout Voltage (mV) 60 SHDN = VIN, VOUT = SENSE = GND 0.0 250 50 0.30 8.0 300 40 Leakage Current vs. Reverse Voltage Ground Current vs. Output Current 9.0 350 30 Input Voltage (V) Input Voltage (V) 200 150 100 160 140 120 50 VIN = 12V, IOUT = 10mA 100 0 -50 -30 -10 10 30 50 70 90 110 Temperature (°C) Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 130 10 100 1000 10000 100000 Frequency (Hz) is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 VOUT vs. VIN Minimum Input Voltage vs Temperature Minimum Input Voltage (V) 3.5 3.0 2.5 IOUT = 10mA IOUT = 50mA IOUT = 80mA IOUT = 100mA 2.0 1.5 VIN (50V/Div) VOUT (2V/Div) 1.0 0.5 IOUT = 50mA 0.0 -50 -25 0 25 50 75 100 Time (1ms/Div) 125 Temperature (°C) Load Transient Response Line Transient Response VIN = 14V, VOUT = 3.3V VIN = 14V, VOUT = 3.3V, IOUT = 1mA to 100mA, COUT = 1μF VOUT_ac (200mV/Div) VIN (10V/Div) VOUT_ac (100mV/Div) IOUT (50mA/Div) IOUT = 20mA Time (25μs/Div) Time (25μs/Div) Load Transient Response Load Transient Response VOUT_ac (50mV/Div) VOUT_ac (200mV/Div) VIN = 14V, VOUT = 3.3V, IOUT = 10mA to 100mA IOUT (50mA/Div) VIN = 14V, VOUT = 3.3V, IOUT = 1mA to 100mA, COUT = 4.7μF Time (25μs/Div) Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 IOUT (50mA/Div) Time (10μs/Div) is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9074 Load Transient Response Power-On at No Load VIN (50V/Div) VOUT_ac (50mV/Div) VIN = 14V, VOUT = 3.3V, IOUT = 10mA to 100mA, COUT = 4.7μF VOUT (1V/Div) IOUT (50mA/Div) VIN = 60V, VOUT = 3.3V, IOUT = 0mA IOUT (50mA/Div) Time (10μs/Div) Time (50μs/Div) Turn-On by SHDN at No Load Power-On at 100mA Load VIN (50V/Div) SHDN (2V/Div) VOUT (1V/Div) VIN = 60V, VOUT = 3.3V, IOUT = 0mA IOUT (50mA/Div) VOUT (1V/Div) IOUT (100mA/Div) Time (50μs/Div) VIN = 60V, VOUT = 3.3V, IOUT = 100mA Time (50μs/Div) Turn-On by SHDN at 100mA Load SHDN (2V/Div) VOUT (1V/Div) IOUT (100mA/Div) VIN = 60V, VOUT = 3.3V, IOUT = 100mA Time (50μs/Div) Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 10 is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 Applications Information The RT9074 is a high input-voltage linear regulator specifically designed to minimize external components. The input voltage range is from 4.5V to 60V. The device supplies 100mA of output current with a maximum dropout voltage of 400mV. The fixed output versions are equipped with internal resistive dividers to set the output voltage to 2.5V, 3.3V, or 5V, respectively. The total resistance of the each internal feedback divider is about 1MΩ The internal dividers connect between SENSE and GND, with the midpoint connecting to the input of the error amplifier. These versions are all internally compensated. Adjustable Output Voltage and Compensation RT9074 The adjustable output versions may be set to provide from 1.25V to 60V, using external feedback voltage divider resistors (Figure 1). These included an internal feedforward compensation capacitor, connected between SENSE and FB, which may be used when regulating at output voltages up to 25V. To achieve the correct compensation (together with your external FB divider, use an upper divider resistor (R1) value between 500kΩ and 1MΩ. Calculate R2 according to the following formula : R2 = R1 / (VOUT / 1.25V − 1). For output voltages greater than 25V an external feedforward capacitor (Figure 2) should be used and SENSE should be left unconnected. Choose a lower divider resistor (R2) at least 10kΩ and calculate R1 according to the following formula : R1 = R2 x (VOUT / 1.25V − 1), Then, calculate the compensation capacitor (CCOMP) value according to the following formula : CCOMP = 25μs / R1. RT9074 CIN 0.18µF VIN RT9074 CIN 0.18µF VIN VOUT SENSE CCOMP R1 COUT 1µF VOUT 1.25V to 60V FB SHDN R2 GND Figure 2. RT9074 Adjustable Output Above 25V Fixed VOUT Applications VIN 4.5V to 60V VIN 4.5V to 60V VOUT SENSE SHDN GND R1 COUT 1µF VOUT 1.25V to 25V Remote-Sense Applications Since VOUT and SENSE (and FB) are separate pins, it is possible to connect SENSE to the output voltage remotely at the load (as long as the output voltage is 25V or less). FB can also be connected remotely, with SENSE unconnected if the output exceeds 25V. Remote sensing eliminates output voltage errors due to any resistive voltage drop between VOUT and the load. (Voltage drops in the ground connection cannot be compensated.) Added External NPN for High-Current Applications Higher output currents and/or increased power dissipation are possible using an external NPN output transistor. VOUT drives the base of the transistor and SENSE and/or FB monitors the actual output voltage, as in normal applications. The fixed-output versions (Figure 3) or adjustable-output version (Figure 4) can be used. Figure 3 and Figure 4 have no current limit and should be used with care. If a crude current limit is desired, add the two diodes and resistor shown in Figure 5. The approximate current limit is 0.7V/R3. Any small switching diodes can be used and size R3 for the power dissipated in R3, which is typically 0.7V x 0.7V / R3. VIN 4.5V to 60V RT9074 CIN 0.18µF VIN MJD31C VOUT 100 SHDN SENSE GND COUT 10µF VOUT 2.5V/3.3V/5V FB R2 Figure 3. RT9074-25/33/50 External Transistor Application Figure 1. RT9074 Adjustable Output Up to 25V Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT9074 PD(MAX) = (TJ(MAX) − TA) / θJA CIN 0.18µF 100 CCOMP SENSE SHDN VOUT 1.25V to 60V COUT 10µF R1 FB GND R2 Figure 4. RT9074 External Transistor Application VIN 4.5V to 60V RT9074 CIN 0.18µF VIN MJD31C VOUT 100 SHDN SENSE GND 1N4148 x 2 R3 COUT 10µF VOUT 2.5V/3.3V/5V Figure 5. RT9074 External Transistor Application with Current Limit Component Selection A low-ESR capacitor such as ceramic type must be connected between VIN and GND with short, wide traces to bypass input noise. RT9074 is designed to work with small input capacitor to reduce the cost from high-voltage low-ESR requirement. To guarantee a minimum 0.1μF input capacitance, a ceramic 0.18μF input capacitor with an appropriate voltage rating is recommended. The RT9074 operates with any reasonable output capacitor including low-ESR ceramic types. Low-ESR aluminum and tantalum capacitor may also be used. A minimum of 1μF is recommended and much higher values are also acceptable. Connect the output capacitor between VOUT and GND with short, wide traces to keep the circuit stable. 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 : Copyright © 2016 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 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. The junction to ambient thermal resistance, θJA, is layout dependent. For SOT-223 package, the thermal resistance, θJA, is 80°C/ W on a standard JEDEC 51-7 four-layer thermal test board. For SOP-8 (Exposed Pad) package, the thermal resistance, θJA, is 30.6°C/W on a standard JEDEC 51-7 four-layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by the following formulas : P D(MAX) = (125°C − 25°C) / (80°C/W) = 1.25W for SOT-223 package PD(MAX) = (125°C − 25°C) / (30.6°C/W) = 3.26W for SOP-8 (Exposed Pad) package The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance, θJA. The derating curves in Figure 6 allow the designer to see the effect of rising ambient temperature on the maximum power dissipation. 4.0 Maximum Power Dissipation (W)1 VIN 4.5V to 60V RT9074 VOUT VIN 3.5 Four-Layer PCB SOP-8 (Exposed Pad) 3.0 2.5 2.0 1.5 SOT-223 1.0 0.5 0.0 Ambient Temperature (°C) Figure 6. Derating Curve of Maximum Power Dissipation is a registered trademark of Richtek Technology Corporation. DS9074-04 May 2016 RT9074 Layout Consideration VOUT COUT VOUT 7 GND VIN CIN 6 GND GND 5 SHDN 8 SENSE 2 NC 3 NC 4 GND 9 VIN Figure 7. PCB Layout Guide Copyright © 2016 Richtek Technology Corporation. All rights reserved. DS9074-04 May 2016 is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT9074 Outline Dimension 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. DS9074-04 May 2016 RT9074 H A M EXPOSED THERMAL PAD (Bottom of Package) Y J X B F C I D Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 4.801 5.004 0.189 0.197 B 3.810 4.000 0.150 0.157 C 1.346 1.753 0.053 0.069 D 0.330 0.510 0.013 0.020 F 1.194 1.346 0.047 0.053 H 0.170 0.254 0.007 0.010 I 0.000 0.152 0.000 0.006 J 5.791 6.200 0.228 0.244 M 0.406 1.270 0.016 0.050 X 2.000 2.300 0.079 0.091 Y 2.000 2.300 0.079 0.091 X 2.100 2.500 0.083 0.098 Y 3.000 3.500 0.118 0.138 Option 1 Option 2 8-Lead SOP (Exposed Pad) 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. DS9074-04 May 2016 www.richtek.com 15