RT9048GSP

® RT9048 2A, Low Input Voltage, Ultra-Low Dropout Linear Regulator with Enable General Description Features The RT9048 is a high performance positive voltage regulator designed for use in applications requiring ultra low input voltage and ultra-low dropout voltage at up to 2A. The feature of ultra-low dropout voltage is ideal for the application where output voltage is very close to input voltage. The input voltage can be as low as 1.4V and the output voltage is adjustable by an external resistive divider as low as 0.5V. The RT9048 provides an excellent output voltage regulation over variations in line, load and temperature. Over-current and over-temperature protection functions are provided. Additionally, an enable pin is designed to further reduce power consumption while shutdown and the shutdown current is as low as 1.5μA.        Applications      The RT9048 is available in the SOP-8 (Exposed Pad) package. Input Voltage as Low as 1.4V Ultra-Low Dropout Voltage 400mV @ 2A Over-Current Protection Over-Temperature Protection 1.5μ μA Input Current in Shutdown Mode Enable Control RoHS Compliant and Halogen Free    Telecom/Networking Cards Motherboards/Peripheral Cards Industrial Applications Wireless Infrastructure Set-Top Box Medical Equipment Notebook Computers Battery Powered Systems Ordering Information Pin Configuration RT9048 (TOP VIEW) Package Type SP : SOP-8 (Exposed Pad-Option 2) NC Lead Plating System G : Green (Halogen Free and Pb Free) 8 EN 2 VIN 3 NC 4 GND ADJ 6 VOUT 5 NC 9 Note : SOP-8 (Exposed Pad) Richtek products are :  RoHS compliant and compatible with the current require- Marking Information ments of IPC/JEDEC J-STD-020.  GND 7 RT9048GSP : Product Number Suitable for use in SnPb or Pb-free soldering processes. RT9048 GSPYMDNN YMDNN : Date Code Simplified Application Circuit VIN VIN RT9048 VOUT EN ADJ C1 Enable R1 GND Copyright © 2019 Richtek Technology Corporation. All rights reserved. DS9048-04 June 2019 VOUT C2 R2 is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9048 Functional Pin Description Pin No. Pin Name 1, 4, 5 NC 2 EN 3 VIN 6 VOUT 7 ADJ 8, GND 9 (Exposed pad) Pin Function No internal connection. Enable control input (Active-High). Pulling this pin below 0.4V turns the regulator off, reducing the quiescent current to a fraction of its operating value. The device will be enabled if this pin is left open. Connect to VIN if not being used. Supply voltage input. For regulation at full load, the input to this pin must be between (VOUT + 0.5V) and 6V. The minimum input voltage is 1.4V. A large bulk capacitance should be placed closely to this pin to ensure that the input supply does not sag below 1.4V. Also, a minimum of 10F ceramic capacitor should be placed directly at this pin. Output voltage. A minimum of 10F capacitor should be placed directly at this pin. Feedback voltage input. If connected to the VOUT pin, the output voltage will be set at 0.5V. If external feedback resistors are used, the output voltage will be determined by the resistor ratio. Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. Functional Block Diagram RSENSE VOUT VIN VPUMP - - + + ADJ VIN 0.5µA 0.5V EN VIN Thermal Shutdown VOUT + VIN - Reference Generator GND Reverse Voltage Shutdown Operation The RT9048 is a low dropout voltage linear regulator designed specially for low external components system. Output Transistor The RT9048 builds in a N-MOSFET output transistor which provides a low switch-on resistance for low dropout voltage applications. Error Amplifier The Error Amplifier compares the internal reference voltage with the output feedback voltage, and controls the Gate voltage of N-MOSFET to support good line regulation and load regulation at output voltage. Copyright © 2019 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 Current-Limit Protection The RT9048 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 resistor. Over-Temperature Protection The over-temperature protection function will turn off the P-MOSFET when the junction temperature exceeds 160°C (typ.). Once the junction temperature cools down by approximately 30°C, the regulator will automatically resume operation. is a registered trademark of Richtek Technology Corporation. DS9048-04 June 2019 RT9048 Absolute Maximum Ratings         (Note 1) Supply Voltage, VIN -----------------------------------------------------------------------------------------------------Other Pins ------------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOP-8 (Exposed Pad) --------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) SOP-8 (Exposed Pad), θJA ---------------------------------------------------------------------------------------------SOP-8 (Exposed Pad), 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 7V −0.3V to 6V 2.04W 49°C/W 15°C/W 260°C 150°C −65°C to 150°C 2kV (Note 4) Supply Voltage, VIN ------------------------------------------------------------------------------------------------------ 1.4V to 6V Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VIN = 1.4V to 6V, IOUT = 10μA to 2A, VADJ = VOUT , TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Quiescent Current IQ VIN = 3.3V, IOUT = 0A -- 0.7 -- mA Shutdown Current ISHDN VIN = 6V, VEN = 0V -- 1.5 10 A Output Voltage VOUT VIN = VOUT + 0.5V, IOUT = 10mA 2 -- 2 % Line Regulation V LINE IOUT = 10mA -- 0.2 -- %/V Load Regulation V LOAD IOUT = 10mA to 2A -- 0.5 -- % IOUT = 1A, VIN  1.6V -- 120 200 IOUT = 1A, 1.4V < VIN < 1.6V -- -- 400 IOUT = 1.5A, VIN  1.6V -- 180 300 IOUT = 1.5A, 1.4V < VIN < 1.6V -- -- 500 IOUT = 2A, VIN  1.6V -- 240 400 IOUT = 2A, 1.4V < VIN < 1.6V -- -- 600 ILIM VIN = 3.3V -- 3 -- A ADJ Reference Voltage VADJ VIN = 3.3V, V ADJ = V OUT, IOUT = 10mA 0.495 -- 0.505 V ADJ Pin Current IADJ VADJ = 0.5V -- 20 200 nA Dropout Voltage Current Limit VDROP VIN = 1.8V, IOUT = 0.8A mV Feedback Copyright © 2019 Richtek Technology Corporation. All rights reserved. DS9048-04 June 2019 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9048 Parameter Symbol Test Conditions Min Typ Max Unit -- 1 10 A Enable EN Pin Current IEN VEN = 0V, VIN = 6V H-Level VENH VIN = 3.3V 0.86 1.08 1.3 L-Level VENL VIN = 3.3V 0.8 1.02 1.24 OTP Trip Level -- 160 -- °C Hysteresis -- 30 -- °C Enable Threshold Voltage V Over-Temperature Protection Note 1. Stresses beyond those listed under “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 © 2019 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 is a registered trademark of Richtek Technology Corporation. DS9048-04 June 2019 RT9048 Typical Application Circuit RT9048 3 VIN VIN VOUT 6 C1 10µF VOUT = R1 2 Enable 0.5(R1+R2) R2 VOUT ADJ 7 EN C2 10µF R2 GND 8, 9 (Exposed Pad) (V) Figure 1. Adjustable Voltage Regulator Copyright © 2019 Richtek Technology Corporation. All rights reserved. DS9048-04 June 2019 is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9048 Typical Operating Characteristics Quiescent Current vs. Temperature Reference Voltage vs. Temperature 1.15 0.520 Quiescent Current (mA) Reference Voltage (V) 0.515 0.510 0.505 VIN = 5V 0.500 VIN = 3.3V 0.495 0.490 0.95 VIN = 5V 0.75 VIN = 3.3V 0.55 0.485 VOUT = 2.52V 0.35 0.480 -50 -25 0 25 50 75 100 -50 125 -25 0 Shutdown Current vs. Temperature 75 100 125 UVLO vs. Temperature 1.20 1.50 1.05 1.40 Rising 1.30 VIN = 5V UVLO (V) Shutdown Current (µA)1 50 Temperature (°C) Temperature (°C) 0.90 25 0.75 VIN = 3.3V 1.20 1.10 Falling 0.60 1.00 0.45 0.90 0.30 0.80 VEN = 5V -50 -25 0 25 50 75 100 125 -50 -25 0 Temperature (°C) Dropout Voltage vs. Load Current 50 75 100 125 EN Threshold Voltage vs. Input Voltage 350 1.5 300 1.4 EN Threshold Voltage (V) Dropout Voltage (mV) 25 Temperature (°C) 125°C 250 25°C 200 150 −40°C 100 50 1.3 Rising 1.2 1.1 1.0 Falling 0.9 0.8 VOUT = 2.5V 0.7 0 0 0.5 1 1.5 Load Current (A) Copyright © 2019 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 2 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 Input Voltage (V) is a registered trademark of Richtek Technology Corporation. DS9048-04 June 2019 RT9048 EN Threshold Voltage vs. Temperature Load Transient Response EN Threshold Voltage (V) 1.5 1.4 VOUT (20mV/Div) 1.3 Rising 1.2 1.1 1.0 IOUT (1A/Div) Falling 0.9 0.8 VIN = 3.3V VIN = 3.3V, VOUT = 2.5V, IOUT = 1A to 2A 0.7 -50 -25 0 25 50 75 100 Time (50μs/Div) 125 Temperature (°C) Line Transient Response Power On from EN VEN (5V/Div) VOUT (2V/Div) VIN (1V/Div) VOUT (10mV/Div) I IN (2A/Div) VIN = 3.3V to 4.3V, VOUT = 2.5V, IOUT = 2A VIN = 3.3V, VOUT = 2.5V, IOUT = 2A Time (500μs/Div) Time (250μs/Div) Power Off from EN PSRR 0 IOUT = 1mA IOUT = 100mA IOUT = 300mA -10 VEN (5V/Div) PSRR (dB) -20 VOUT (2V/Div) I IN (2A/Div) -30 -40 -50 -60 -70 VIN = 3.25V to 3.35V, VOUT = 2.5V VIN = 3.3V, VOUT = 2.5V, IOUT = 2A -80 Time (250μs/Div) 100 1000 10000 100000 1000000 Frequency (Hz) Copyright © 2019 Richtek Technology Corporation. All rights reserved. DS9048-04 June 2019 is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9048 Application Information Output Voltage Setting The RT9048 output voltage is adjustable from 0.5V to VIN − VDROP via the external resistive voltage divider. The voltage divider resistors can have values of up to 800kΩ because of the very high impedance and low bias current of the sense comparator. The output voltage is set according to the following equation : VOUT = VADJ   1+ R1   R2  where VADJ is the reference voltage with a typical value of 0.5V. Chip Enable Operation The RT9048 goes into sleep mode when the EN pin is in a logic low condition. In this condition, the pass transistor, error amplifier, and band gap are all turned off, reducing the supply current to only 10μA (max.). The EN pin can be directly tied to VIN to keep the part on. UVLO Protection The RT9048 provides an input under-voltage lockout protection (UVLO). When the input voltage exceeds the UVLO rising threshold voltage (1.2V typ.), the device resets the internal circuit and prepares for operation. If the input voltage falls below the UVLO falling threshold voltage during normal operation, the device will be shut down. A hysteresis (140mV typ.) between the UVLO rising and falling threshold voltage is designed to avoid noise. CIN and COUT Selection Like any low dropout regulator, the external capacitors of the RT9048 must be carefully selected for regulator stability and performance. Using a capacitor of at least 10μF is suitable. The input capacitor must be located at a distance of not more than 0.5 inch from the input pin of the IC. Any good quality ceramic capacitor can be used. However, a capacitor with larger value and lower ESR (Equivalent Series Resistance) is recommended since it will provide better PSRR and line transient response. The RT9048 is designed specifically to work with low ESR ceramic output capacitor for space saving and performance consideration. Using a ceramic capacitor with capacitance of at least 10μF and ESR larger than 1mΩ on the RT9048 output ensures stability. Nevertheless, the RT9048 can still work well with other types of output capacitors due to its wide range of stable ESR. Figure 3 shows the allowable ESR range as a function of load current for various output capacitance. Output capacitors with larger capacitance can reduce noise and improve load transient response, stability, and PSRR. The output capacitor should be located at a distance of not more than 0.5 inch from the output pin of the RT9048. Region of Stable COUT ESR vs. Load Current 100 Unstable Range 10 COUT ESR (Ω) The RT9048 is a low voltage, low dropout linear regulator with an external bias supply input capable of supporting an input voltage range from 1.4V to 6V. 1 Stable Range 0.1 Current Limit The RT9048 contains an independent current limit circuitry, which monitors and controls the pass transistor's gate voltage, limiting the output current to 3A (typ.). 0.01 VIN = 3.3V, VOUT = 2.5V, COUT = 10μF / X7R 0.001 0.0 0.3 0.5 0.8 1.0 Load Current (A) Figure 3 Copyright © 2019 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 is a registered trademark of Richtek Technology Corporation. DS9048-04 June 2019 RT9048 Thermal Considerations Thermal protection limits power dissipation in the RT9048. When the operation junction temperature exceeds 160°C, the OTP circuit starts the thermal shutdown function and turns the pass element off. The pass element turns on again after the junction temperature cools by 30°C. The RT9048 output voltage will be closed to zero when output short circuit occurs as shown in Figure 4. It can reduce the IC temperature and provides maximum safety to end users when output short circuit occurs. VOUT Short to GND For recommended operating condition specifications, the maximum junction temperature is 125°C. The junction to ambient thermal resistance, θJA, is layout dependent. For SOP-8 (Exposed Pad) package, the thermal resistance, θJA, is 49°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 formula : P D(MAX) = (125°C − 25°C) / (49°C/W) = 2.04W for SOP-8 (Exposed Pad) package The maximum power dissipation depends on the operating ambient temperature for fixed T J(MAX) and thermal resistance, θJA. The derating curve in Figure 5 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. VOUT ILIM IOUT IC Temperature Figure 4. Short Circuit Protection when Output Short Circuit Occurs 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 : 3.2 Maximum Power Dissipation (W) ILIM’ Four-Layer PCB 2.8 2.4 2.0 1.6 1.2 0.8 0.4 0.0 0 25 50 75 100 125 Ambient Temperature (°C) Figure 5. Derating Curve of Maximum Power Dissipation 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. Copyright © 2019 Richtek Technology Corporation. All rights reserved. DS9048-04 June 2019 is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9048 Outline Dimension 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. 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 10 DS9048-04 June 2019