RT2519GQV(2)

® RT2519 1A, Low Noise, Ultra High PSRR, Low-Dropout Linear Regulator General Description Features The RT2519 is a high performance positive low dropout (LDO) regulator designed for applications requiring very low dropout voltage and ultra high Power Supply Ripple Rejection (PSRR) at up to 1A. The input voltage range is from 2.2V to 6V and the output voltage is programmable as low as 0.8V. A P-MOSFET switch provides excellent transient response with just a 4.7μF ceramic output capacitor. The external enable control effectively reduces power dissipation while shutdown and further output noise immunity is achieved through bypass capacitor on NR pin. Additionally, the RT2519 features a precise 3% output regulation over line, load, and temperature variations. The device is available in the VDFN-8AL 3x3 package and is specified from −40°C to 125°C.  Very Low Dropout : 170mV Typical at 1A  Ultra High PSRR : 63dB @ 1kHz, 38dB @ 1MHz Input Voltage Range : 2.2V to 6V Adjustable Output Voltage : 0.8V to 5.5V −40°°C to 125°°C Operating Junction Temperature Range Excellent Noise Immunity Fast Response Over Load and Line Transient Stable with a 4.7μ μF Output Ceramic Capacitor Accurate Output Voltage 3% Over Load, Line, Process, and Temperature Variations Enable Control Over-Current Protection Over-Temperature Protection Ordering Information Applications RT2519             Pin 1 Orientation*** (2) : Quadrant 2, Follow EIA-481-D   Package Type QV : VDFN-8AL 3x3 (V-Type)   Lead Plating System G : Green (Halogen Free and Pb Free)   Note : Telecom/Networking Cards Motherboards/Peripheral Cards Industrial Applications Wireless Infrastructures Set-Top Boxes Medical Equipments Notebook Computers Battery Powered Systems ***Empty means Pin1 orientation is Quadrant 1 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. Simplified Application Circuit RT2519 VIN VIN VOUT EN FB CIN Enable R1 CNR Copyright © 2017 Richtek Technology Corporation. All rights reserved. COUT R2 NR DS2519-03 August 2017 VOUT GND is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT2519 Pin Configuration Marking Information KN= : Product Code (TOP VIEW) VOUT 1 8 VIN VOUT 2 7 VIN FB 3 6 NR GND 4 5 EN GND 9 KN=YM DNN YMDNN : Date Code VDFN-8AL 3x3 Functional Pin Description Pin No. 1, 2 3 Pin Name Pin Function VOUT Output of the regulator. Decouple this pin to GND with at least 4.7F for stability. FB Feedback voltage input. This pin is used to set the desired output voltage via an external resistive divider. The feedback reference voltage is 0.8V typically. 4, 9 (Exposed Pad) GND System ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. 5 EN Enable control input. Connecting this pin to logic high enables the regulator or driving this pin low puts it into shutdown mode. EN can be connected to IN if not used. (EN pin is not allowed to be left floating.) 6 NR Noise reduction input. Decouple this pin to GND with an external capacitor can not only reduce output noise to very low levels but also slow down the VOUT rise like a soft-start behavior. 7, 8 VIN Supply input. A minimum of 1F ceramic capacitor should be placed as close as possible to this pin for better noise rejection. Functional Block Diagram VOUT VIN UVLO Control Logic Quick Start-Up Bandgap + EN Thermal Protection Current Limit FB NR GND Copyright © 2017 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS2519-03 August 2017 RT2519 Operation The RT2519 is a low noise, high PSRR LDO which supports very low dropout operation. The operating input range from 2.2V to 6V and the output voltage is programmable as low to 0.8V and the output current can be up to 1A. The internal compensation network is well designed to achieve fast transient response with good stability. In steady-state operation, the feedback voltage is regulated to the reference voltage by the internal regulator. When the feedback voltage signal is less than the reference, the output current passes through the power MOSFET will be increased. The extra amount of the current is sent to the output until the voltage level of FB pin returns to the reference. On the other hand, if the feedback voltage is higher than the reference, the power MOSFET current is decreased. The excess charge at the output can be released by the loading current. Start-Up The RT2519 has a quick-start circuit to charge the noise reduction capacitor (CNR). The switch of the quick-start circuit is closed at start up. To reduce the noise from bandgap, there is a low-pass (RC) filter consist of the CNR and the resistance which is connected with bandgap, as Functional Block Diagrams present. At the start-up, the quick-start switch is closed, with only 35kΩ resistance between bandgap and NR pin. The quickstart switch opens approximate 2ms after the device is enabled, the resistance between NR and bandgap is about 224kΩ to form a very good low pass filter and with great noise reduction performance. opens the quick-start switch, the CNR will be charged through higher resistance 224kΩ and takes much longer time to finish the start up process. Enable and Shutdown Operation The RT2519 goes into sleep mode when the EN pin is in a logic low condition. In this condition, the pass transistor, error amplifier, and bandgap are all turned off, reducing the supply current to only 2μA (max.). If the shutdown mode is not required, the EN pin can be directly tied to VIN pin to keep the LDO on. Current Limit The RT2519 continuously monitors the output current to protect the pass transistor against abnormal operations. When an overload or short circuit is encountered, the current limit circuitry controls the pass transistor's gate voltage to limit the output within the predefined range. By reason of the build-in body diode, the pass transistor conducts current when the output voltage exceeds input voltage. Since the current is not limited, external current protection should be added if device may work at reverse voltage state. Over-Temperature Protection (OTP) The RT2519 has an over-temperature protection. When the device triggers the OTP, the device shuts down until the temperature back to normal state. Under Voltage Lock-Out (UVLO) The RT2519 utilizes an under voltage lock-out circuit to keep the output shut off until the internal circuitry is operating properly. The UVLO circuit has a de-glitch feature so that it typically ignores undershoot transients on the input if they are less than 30μs duration. The 35kΩ resistance is used to slow down the reference voltage ramp to avoid inrush current at chip start-up, and the start-up time can be calculated as : tSS (sec) = 160000 x CNR (F) (1) It is recommend the CNR value larger than 0.01μF to reduce noise, and low leakage ceramic capacitors are suitable. However, with too large CNR will extend the start-up time very long if the CNR is not fully charged during 2ms and Copyright © 2017 Richtek Technology Corporation. All rights reserved. DS2519-03 August 2017 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT2519 Absolute Maximum Ratings        (Note 1) All Pins ---------------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C VDFN-8AL 3x3 ------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) VDFN-8AL 3x3, θJA -------------------------------------------------------------------------------------------------------VDFN-8AL 3x3, θJC ------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Model) ---------------------------------------------------------------------------------------------CDM (Charged Device Model) ------------------------------------------------------------------------------------------ Recommended Operating Conditions   −0.3V to 7V 3.31W 30.2°C/W 5.5°C/W 260°C 150°C −65°C to 150°C 2kV 1kV (Note 4) Supply Voltage, VIN ------------------------------------------------------------------------------------------------------ 2.2V to 6V Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C Electrical Characteristics (VIN = VOUT + 0.5V or 2.2V, VOUT = 0.8V and 5.5V, IOUT = 1mA, VEN = 2.2V, CNR = 10nF, COUT = 4.7μF, TJ = −40°C to 125°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max 2.2 -- 6 Unit Supply Voltage Input Operating Voltage VIN V Under-Voltage Lockout Threshold VUVLO ROUT = 1k 1.86 2 2.1 Under-Voltage Lockout Threshold Hysteresis VUVLO ROUT = 1k -- 200 -- mV Shutdown Current ISHDN VEN  0.4V, VIN  2.2V, ROUT = 1k, 0°C  TJ  85°C -- 0.2 2 A Quiescent Current IQ -- 190 350 A 0.8 -- 5.5 V VOUT + 0.5V  VIN  6V, VIN  2.5V, 100mA  IOUT  500mA, 0°C  TJ  85°C 2 -- +2 VOUT + 0.5V  VIN  6V, VIN  2.2V, 100mA  IOUT  1A 3 ±0.3 +3 VOUT + 0.5V  VIN  6V, VIN  2.2V, IOUT = 100mA -- 0.2 -- % -- 0.3 -- % Output Voltage Output Supply Voltage Output Supply Voltage Accuracy (Note 5) VOUT Line Regulation VOUT/VIN Load Regulation VOUT/IOUT 100mA  IOUT  1A Copyright © 2017 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 % is a registered trademark of Richtek Technology Corporation. DS2519-03 August 2017 RT2519 Parameter Symbol Test Conditions Min Typ Max 1.2 -- -- Unit Enable Voltage 2.2V  VIN  6V, ROUT = 1k VIH VEN rising VIL VEN falling, ROUT = 1k -- -- 0.4 Enable Input Current IIH VIN = 6V, VEN = 6V -- 0.02 1 A Feedback Input Current IFB VIN = 5.5V, VFB = 0.8V -- 0.02 1 A ILIM VIN = 3.3V, VOUT = 0.85 x VOUT 1.1 1.4 2 A CNR = 1nF -- 0.16 -- CNR = 10nF -- 1.6 -- VIN  2.2V, IOUT = 500mA -- -- 250 VOUT + 0.5V  VIN  6V, VIN  2.5V, VFB = 0V IOUT = 750mA -- -- 350 VIN  2.5V, IOUT = 1A -- -- 500 f = 100Hz -- 48 -- VIN = 4.3V, VOUT = 3.3V, f = 1kHz IOUT = 750mA f = 10kHz -- 63 -- -- 63 -- f = 1MHz -- 38 -- CNR = 1nF -- -- BW = 100Hz to 100kHz, VIN = 4.3V, VOUT = 3.3V, CNR = 10nF IOUT = 100mA 15.6 x VOUT -- 15.6 x VOUT -- CNR = 0.1F -- 15.1 x VOUT -- -- 160 -- -- 140 -- Enable Threshold Voltage V Current Limit Output Current Limit Power-Up Time VOUT = 3.3V, ROUT = 3.3k, COUT = 4.7F Power-Up Time ms Dropout Voltage Dropout Voltage VDROP mV Power Supply Ripple Rejection and Noise Power Supply Ripple Rejection PSRR Output Noise Voltage dB VRMS Over-Temperature Protection Thermal Shutdown TSD Thermal Shutdown Recovery Copyright © 2017 Richtek Technology Corporation. All rights reserved. DS2519-03 August 2017 °C is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT2519 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 under natural convection (still air) at TA = 25°C with the component mounted on a high effectivethermal-conductivity four-layer test board on a JEDEC 51-7 thermal measurement standard. 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. Note 5. The spec. doesn't cover the tolerances from external resistors, and which is not tested at condition of VOUT = 0.8V, 4.5V ≤ VIN ≤ 6V, and 750mA ≤ IOUT ≤ 1A since the power dissipation of the device is totally higher than the maximum rating of the package to lead a thermal shutdown issue. Typical Application Circuit VIN 2.2V to 6V Enable 7, 8 RT2519 VIN CIN 1µF VOUT 1, 2 VOUT R1 5 EN 6 NR CNR 10nF FB 3 COUT 4.7µF R2 GND 4, 9 (Exposed Pad) Note : All input and output capacitance in the suggested parameter mean the effective capacitance. The effective capacitance needs to consider any De-rating Effect like DC bias. Copyright © 2017 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 is a registered trademark of Richtek Technology Corporation. DS2519-03 August 2017 RT2519 Typical Operating Characteristics UVLO vs. Temperature Reference Voltage vs. Temperature 2.2 0.810 Logic-High 0.805 2.0 UVLO (V) Reference Voltage (V) 2.1 VIN = 2.2V VIN = 3.3V VIN = 4.3V VIN = 5.5V VIN = 6V 0.800 0.795 1.9 Logic-Low 1.8 1.7 1.6 VOUT = 0.8V, VEN = 2.2V IOUT = 1mA 1.5 0.790 -50 -25 0 25 50 75 100 -50 125 -25 0 Temperature (°C) Shutdown Current vs. Temperature 50 75 100 125 Dropout Voltage vs. Input Voltage 200 VEN = 0.4V 2.0 Dropout Voltage (mV) Shutdown Current (μA)1 2.5 25 Temperature (°C) VIN = 2.2V VIN = 3.3V VIN = 4.3V VIN = 5V VIN = 5.5V VIN = 6V 1.5 1.0 0.5 125°C 85°C 25°C 0°C −40°C 150 100 50 IOUT = 1000mA 0.0 0 -50 -25 0 25 50 75 100 125 2 3 Temperature (°C) Dropout Voltage vs. Output Current 5 6 PSRR vs. Frequency 90 200 125°C 85°C 25°C 0°C −40°C 150 80 70 PSRR (dB) Dropout Voltage (mV) 4 Input Voltage (V) 100 50 60 IOUT = 10mA IOUT = 100mA IOUT = 750mA IOUT = 1000mA 50 40 30 20 VIN = 2.5V 0 No CIN, VIN = 4.3V, COUT = 4.7μF, VOUT = 3.3V 10 0 0 200 400 600 800 Output Current (mA) Copyright © 2017 Richtek Technology Corporation. All rights reserved. DS2519-03 August 2017 1000 10 100 1k 10k 100k 1M 10M Frequency (Hz) is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 Output Spectral Noise Density (μV/√ Hz) RT2519 Output Spectral Noise Density 100.00 Load Transient Response RMS Noise (100Hz to 100kHz) 69.72μVRMS (IOUT = 10mA), 59.01μVRMS (IOUT = 100mA), 56.11μVRMS (IOUT = 750mA) VOUT = 3.3V, VIN = 3.8V, COUT = 4.7μF, CNR = 0.01μF 10.00 VIN = 4.3V, VOUT = 3.3V, IOUT = 0.1A to 1A (1A/μs, only shows the transient component) VOUT (50mV/Div) 1.00 IOUT = 10mA IOUT = 100mA IOUT = 750mA 0.10 IOUT (500mA/Div) 0.01 10 100 1000 10000 100000 Time (50μs/Div) Frequency (Hz) Line Transient Response Power On from EN VEN (2V/Div) VOUT (5mV/Div) VIN (1V/Div) VIN = 3.8V to 4.8V, VOUT = 3.3V, IOUT = 0.1A Time (50μs/Div) VOUT (1V/Div) IOUT (500mA/Div) VIN = 4.3V, VOUT = 3.3V Time (500μs/Div) Power Off from EN VEN (2V/Div) VOUT (1V/Div) IOUT (500mA/Div) VIN = 4.3V, VOUT = 3.3V Time (50μs/Div) Copyright © 2017 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 is a registered trademark of Richtek Technology Corporation. DS2519-03 August 2017 RT2519 Application Information The RT2519 is a low voltage, low dropout linear regulator with input voltage from 2.2V to 6V and a fixed output voltage from 0.8V to 5.5V. Dropout Voltage The dropout voltage refers to the voltage difference between the VIN and VOUT pins while operating at specific output current. The dropout voltage VDO also can be expressed as the voltage drop on the pass-FET at specific output current(IRATED) while the pass-FET is fully operating at ohmic region and the pass-FET can be characterized as an resistance RDS(ON). Thus the dropout voltage can be defined as (VDO = VVIN − VVOUT = RDS(ON) x IRATED). For normal operation, the suggested LDO operating range is (VVIN > VVOUT + VDO) for good transient response and PSRR ability. Vice versa, while operating at the ohmic region will degrade these performance severely. Output Voltage Setting For the RT2519, the voltage on the FB pin sets the output voltage and is determined by the values of R1 and R2. The values of R1 and R2 can be calculated for any voltage using the formula given in Equation : VOUT = R1 + R2  R2  0.8 Using lower values for R1 and R2 is recommended to reduces the noise injected from the FB pin. Note that R1 is connected from VOUT pin to FB pin, and R2 is connected from FB to GND. Chip Enable Operation The EN pin is the chip enable input. Pull the EN pin low (1.2V,