Triple, 200 mA, Low Noise, High PSRR Voltage Regulator ADP320 FEATURES TYPICAL APPLICATION CIRCUITS 2.5V TO VBIAS 5.5V 1.8V TO VIN1/VIN2 5.5V ADP320 + + VBIAS 1µF 1µF EN1 LDO 1 ON EN LD1 OFF VOUT1 + 1µF VBIAS EN2 ON OFF LDO 2 EN LD2 VOUT2 + 1µF VBIAS 1.8V TO VIN3 5.5V + 1µF EN3 ON OFF LDO 3 EN LD3 VOUT3 + 1µF GND 02839-001 Bias voltage range (VBIAS): 2.5 V to 5.5 V LDO input voltage range (VIN1/VIN2, VIN3): 1.8 V to 5.5 V Three 200 mA low dropout voltage regulators 16-lead, 3 mm × 3 mm LFCSP Initial accuracy: ±1% Stable with 1 μF ceramic output capacitors No noise bypass capacitor required 3 independent logic controlled enables Over current and thermal protection Key specifications High PSRR 76 dB PSRR up to 1 kHz 70 dB PSRR 10 kHz 60 dB PSRR at 100 kHz 40 dB PSRR at 1 MHz Low output noise 29 μV rms typical output noise at VOUT = 1.2 V 55 μV rms typical output noise at VOUT = 2.8 V Excellent transient response Low dropout voltage: 110 mV @ 200 mA load 85 μA typical ground current at no load, all LDOs enabled 100 μs fast turn-on circuit Guaranteed 200 mA output current per regulator −40°C to +125°C junction temperature Figure 1. Typical Application Circuit APPLICATIONS Mobile phones Digital cameras and audio devices Portable and battery-powered equipment Portable medical devices Post dc-to-dc regulation GENERAL DESCRIPTION The ADP320 200 mA triple output LDO combines high PSRR, low noise, low quiescent current, and low dropout voltage in a voltage regulator ideally suited for wireless applications with demanding performance and board space requirements. The low quiescent current, low dropout voltage, and wide input voltage range of the ADP320 triple LDO extend the battery life of portable devices. The ADP320 triple LDO maintains power supply rejection greater than 60 dB for frequencies as high as 100 kHz while operating with a low headroom voltage. The ADP320 triple LDO offers much lower noise performance than competing LDOs without the need for a noise bypass capacitor. The ADP320 triple LDO is available in a miniature 16-lead 3 mm × 3 mm LFCSP package and is stable with tiny 1 μF ±30% ceramic output capacitors, resulting in the smallest possible board area for a wide variety of portable power needs. The ADP320 triple LDO is available in output voltage combinations ranging from 0.8 V to 3.3 V and offers over current and thermal protection to prevent damage in adverse conditions. Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2010 Analog Devices, Inc. All rights reserved. ADP320 TABLE OF CONTENTS Features .............................................................................................. 1 Typical Performance Characteristics ..............................................7 Applications ....................................................................................... 1 Theory of Operation ...................................................................... 14 Typical Application Circuits............................................................ 1 Applications Information .............................................................. 15 General Description ......................................................................... 1 Capacitor Selection .................................................................... 15 Revision History ............................................................................... 2 Undervoltage Lockout ............................................................... 16 Specifications..................................................................................... 3 Enable Feature ............................................................................ 16 Input and Output Capacitor, Recommended Specifications .. 4 Current-Limit and Thermal Overload Protection ................. 17 Absolute Maximum Ratings............................................................ 5 Thermal Considerations............................................................ 17 Thermal Resistance ...................................................................... 5 Printed Circuit Board Layout Considerations ....................... 19 ESD Caution .................................................................................. 5 Outline Dimensions ....................................................................... 20 Pin Configurations and Function Descriptions ........................... 6 Ordering Guide .......................................................................... 20 REVISION HISTORY 6/10—Revision 0: Initial Version Rev. 0 | Page 2 of 20 ADP320 SPECIFICATIONS VIN1/VIN2 = VIN3 = (VOUT + 0.5 V) or 1.8 V (whichever is greater), VBIAS = 2.5 V, EN1, EN2, EN3 = VBIAS, IOUT1 = IOUT2 = IOUT3 = 10 mA, CIN = COUT1 = COUT2 = COUT3 = 1 μF, and TA = 25°C, unless otherwise noted. Table 1. Parameter INPUT BIAS VOLTAGE RANGE INPUT LDO VOLTAGE RANGE GROUND CURRENT WITH ALL REGULATORS ON Symbol VBIAS VIN1/VIN2/ VIN3 IGND Conditions TJ = −40°C to +125°C TJ = −40°C to +125°C IOUT = 0 μA Min 2.5 1.8 IBIAS SHUTDOWN CURRENT IGND-SD OUTPUT VOLTAGE ACCURACY VOUT LINE REGULATION ∆VOUT/∆VIN LOAD REGULATION 1 ∆VOUT/∆IOUT DROPOUT VOLTAGE 2 VDROPOUT Max 5.5 5.5 Unit V V μA 160 μA μA μA μA μA μA μA μA μA % % 85 IOUT = 0 μA, TJ = −40°C to +125°C IOUT = 10 mA IOUT = 10 mA, TJ = −40°C to +125°C IOUT = 200 mA IOUT = 200 mA, TJ = −40°C to +125°C INPUT BIAS CURRENT Typ 120 220 250 380 66 TJ = −40°C to +125°C EN1 = EN2 = EN3 = GND EN1 = EN2 = EN3 = GND, TJ = −40°C to +125°C 100 μA < IOUT < 200 mA, VIN = (VOUT + 0.5 V) to 5.5 V, TJ = −40°C to +125°C VIN = (VOUT + 0.5 V) to 5.5 V VIN = (VOUT + 0.5 V) to 5.5 V, TJ = −40°C to +125°C IOUT = 1 mA to 200 mA IOUT = 1 mA to 200 mA, TJ = −40°C to +125°C VOUT = 3.3 V IOUT = 10 mA IOUT = 10 mA, TJ = −40°C to +125°C IOUT = 200 mA IOUT = 200 mA, TJ = −40°C to +125°C VOUT = 3.3 V, all VOUT initially off, enable one VOUT = 0.8 V VOUT = 3.3 V, one VOUT initially on, enable second VOUT = 0.8 V START-UP TIME 3 TSTART-UP CURRENT LIMIT THRESHOLD 4 THERMAL SHUTDOWN Thermal Shutdown Threshold Thermal Shutdown Hysteresis EN INPUT EN Input Logic High EN Input Logic Low EN Input Leakage Current ILIMIT TSSD TSSD-HYS TJ rising VIH VIL VI-LEAKAGE 2.5 V ≤ VBIAS ≤ 5.5 V 2.5 V ≤ VBIAS ≤ 5.5 V EN1 = EN2 = EN3 = VIN or GND EN1 = EN2 = EN3 = VIN or GND, TJ = −40°C to +125°C UNDERVOLTAGE LOCKOUT Input Bias Voltage (VBIAS) Rising Input Bias Voltage (VBIAS) Falling Hysteresis OUTPUT NOISE UVLO UVLORISE UVLOFALL UVLOHYS OUTNOISE 140 0.1 2.5 +1 +2 −1 −2 0.01 −0.03 +0.03 0.001 0.005 6 9 110 170 250 240 100 160 20 360 600 155 15 °C °C 1.2 0.4 0.1 1 2.45 2.0 10 Hz to 100 kHz, VIN = 5 V, VOUT = 3.3 V 10 Hz to 100 kHz, VIN = 5 V, VOUT = 2.8 V 10 Hz to 100 kHz, VIN = 3.6 V, VOUT = 2.5 V 10 Hz to 100 kHz, VIN = 3.6 V, VOUT = 1.2 V Rev. 0 | Page 3 of 20 180 63 55 50 29 %/ V %/ V %/mA %/mA mV mV mV mV mV μs μs μs μs mA V V μA μA V V mV μV rms μV rms μV rms μV rms ADP320 Parameter POWER SUPPLY REJECTION RATIO Symbol PSRR Conditions VIN = 1.8 V, VOUT = 0.8 V, IOUT = 100 mA 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz VIN = 3.8 V, VOUT = 2.8 V, IOUT = 100 mA 100 Hz 1 kHz 10 kHz 100 kHz 1 MHz Min Typ Max Unit 70 70 70 60 40 dB dB dB dB dB 68 62 68 60 40 dB dB dB dB dB 1 Based on an end-point calculation using 1 mA and 200 mA loads. Dropout voltage is defined as the input-to-output voltage differential when the input voltage is set to the nominal output voltage. This applies only for output voltages above 1.8 V. 3 Start-up time is defined as the time between the rising edge of ENx to VOUTx being at 90% of its nominal value. 4 Current-limit threshold is defined as the current at which the output voltage drops to 90% of the specified typical value. For example, the current limit for a 3.0 V output voltage is defined as the current that causes the output voltage to drop to 90% of 3.0 V, or 2.7 V. 2 INPUT AND OUTPUT CAPACITOR, RECOMMENDED SPECIFICATIONS Table 2. Parameter MINIMUM INPUT AND OUTPUT CAPACITANCE 1 CAPACITOR ESR 1 Symbol CMIN RESR Conditions TA = −40°C to +125°C TA = −40°C to +125°C Min 0.70 0.001 Typ Max 1 Unit μF Ω The minimum input and output capacitance should be greater than 0.70 μF over the full range of operating conditions. The full range of operating conditions in the application must be considered during device selection to ensure that the minimum capacitance specification is met. X7R and X5R type capacitors are recommended, Y5V and Z5U capacitors are not recommended for use with LDOs. Rev. 0 | Page 4 of 20 ADP320 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter VIN1/VIN2, VIN3, VBIAS to GND VOUT1, VOUT2 to GND VOUT3 to GND EN1, EN2, EN3 to GND Storage Temperature Range Operating Junction Temperature Range Soldering Conditions Rating –0.3 V to +6.5 V –0.3 V to VIN1/VIN2 –0.3 V to VIN3 –0.3 V to +6.5 V –65°C to +150°C –40°C to +125°C JEDEC J-STD-020 Stresses above those listed under absolute maximum ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. THERMAL DATA Absolute maximum ratings apply individually only, not in combination. The ADP320 triple LDO can be damaged when the junction temperature limits are exceeded. Monitoring ambient temperature does not guarantee that the junction temperature (TJ) is within the specified temperature limits. In applications with high power dissipation and poor thermal resistance the maximum ambient temperature may have to be derated. In applications with moderate power dissipation and low PCB thermal resistance, the maximum ambient temperature can exceed the maximum limit as long as the junction temperature is within specification limits. The junction temperature (TJ) of the device is dependent on the ambient temperature (TA), the power dissipation of the device (PD), and the junction-to-ambient thermal resistance of the package (θJA). Maximum junction temperature (TJ) is calculated from the ambient temperature (TA) and power dissipation (PD) using the following formula: TJ = TA + (PD × θJA) Junction-to-ambient thermal resistance (θJA) of the package is based on modeling and calculation using a 4-layer board. The junction-to-ambient thermal resistance is highly dependent on the application and board layout. In applications where high maximum power dissipation exists, close attention to thermal board design is required. The value of θJA may vary, depending on PCB material, layout, and environmental conditions. The specified values of θJA are based on a four-layer, 4-inch × 3-inch circuit board. Refer to JEDEC JESD 51-9 for detailed information on the board construction. For additional information, see the AN-617 Application Note, MicroCSP™ Wafer Level Chip Scale Package. ΨJB is the junction to board thermal characterization parameter with units of °C/W. ΨJB of the package is based on modeling and calculation using a 4-layer board. The JESD51-12, Guidelines for Reporting and Using Package Thermal Information, states that thermal characterization parameters are not the same as thermal resistances. ΨJB measures the component power flowing through multiple thermal paths rather than a single path as in thermal resistance, θJB. Therefore, ΨJB thermal paths include convection from the top of the package as well as radiation from the package; factors that make ΨJB more useful in realworld applications. Maximum junction temperature (TJ) is calculated from the board temperature (TB) and power dissipation (PD) using the following formula TJ = TB + (PD × ΨJB) Refer to JEDEC JESD51-8 and JESD51-12 for more detailed information about ΨJB. THERMAL RESISTANCE θJA and ΨJB are specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages. Table 4. Package Type 16-Lead 3 mm × 3 mm LFCSP ESD CAUTION Rev. 0 | Page 5 of 20 θJA 49.5 ΨJB 25.2 Unit °C/W ADP320 13 NC EN1 1 12 GND VBIAS 2 11 GND ADP320 VIN1/VIN2 3 10 VIN3 VIN1/VIN2 4 VIN3 NC 8 VOUT3 7 VOUT2 6 VOUT1 5 9 TOP VIEW (Not to Scale) NOTES 1. NC = NO CONNECT. 2. CONNECT EXPOSED PAD TO GROUND PLANE. 02839-002 14 NC 16 EN2 15 EN3 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS Figure 2. Pin Configuration Table 5. Pin Function Descriptions Pin No. 1 Mnemonic EN1 2 3 VBIAS VIN1/VIN2 4 VIN1/VIN2 5 6 7 8 9 10 11 12 13 14 15 VOUT1 VOUT2 VOUT3 NC VIN3 VIN3 GND GND NC NC EN3 16 EN2 EP EP Description Enable Input for Regulator 1. Drive EN1 high to turn on Regulator 1; drive it low to turn off Regulator 1. For automatic startup, connect EN1 to VBIAS. Input Voltage Bias Supply. Bypass VBIAS to GND with a 1 μF or greater capacitor. Regulator Input Supply for Output Voltage 1 and Output Voltage 2. Bypass VIN1/VIN2 to GND with a 1 μF or greater capacitor. Regulator Input Supply for Output Voltage 1 and Output Voltage 2. Bypass VIN1/VIN2 to GND with a 1 μF or greater capacitor. Regulated Output Voltage 1. Connect a 1 μF or greater output capacitor between VOUT1 and GND. Regulated Output Voltage 2. Connect a 1 μF or greater output capacitor between VOUT2 and GND. Regulated Output Voltage 3. Connect a 1 μF or greater output capacitor between VOUT3 and GND. Not connected internally. Regulator Input Supply for Output Voltage 3. Bypass VIN3 to GND with a 1 μF or greater capacitor. Regulator Input Supply for Output Voltage 3. Bypass VIN3 to GND with a 1 μF or greater capacitor. Ground Pin. Ground Pin. Not connected internally. Not connected internally. Enable Input for Regulator 3. Drive EN3 high to turn on Regulator 3; drive it low to turn off Regulator 3. For automatic startup, connect EN3 to VBIAS. Enable Input for Regulator 2. Drive EN1 high to turn on Regulator 2; drive it low to turn off Regulator 2. For automatic startup, connect EN2 to VBIAS. Exposed pad for enhanced thermal performance. Connect to copper ground plane. Rev. 0 | Page 6 of 20 ADP320 TYPICAL PERFORMANCE CHARACTERISTICS VIN1/VIN2 = VIN3 =VBIAS = 4 V, VOUT1 = 3.3 V, VOUT2 = 1.8 V, VOUT3 = 1.5 V, IOUT = 10 mA, CIN = COUT1 = COUT2 = COUT3 = 1 μF, TA = 25°C, unless otherwise noted. 1.820 3.33 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 3.32 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.815 1.810 3.31 VOUT (V) VOUT (V) 1.805 3.30 1.800 1.795 3.29 1.790 3.28 1.785 –5 25 85 125 –40 02839-003 –40 TJ (°C) 85 125 Figure 6. Output Voltage vs. Junction Temperature 3.320 1.820 3.315 1.815 VOUT (V) 3.310 1.810 1.805 3.305 10 100 1000 ILOAD (mA) 1 02839-004 1 1000 Figure 7. Output Voltage vs. Load Current 3.320 1.820 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA VOUT (V) 1.815 3.310 3.305 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.810 1.805 3.8 4.0 4.2 4.4 4.6 4.8 5.0 VIN (V) 5.2 5.4 1.800 2.1 02839-005 3.300 3.6 100 ILOAD (mA) Figure 4. Output Voltage vs. Load Current 3.315 10 02839-007 1.800 3.300 2.5 2.9 3.3 3.7 4.1 4.5 4.9 VIN (V) Figure 5. Output Voltage vs. Input Voltage Figure 8. Output Voltage vs. Input Voltage Rev. 0 | Page 7 of 20 5.3 02839-008 VOUT (V) 25 TJ (°C) Figure 3. Output Voltage vs. Junction Temperature VOUT (V) –5 02839-006 1.780 3.27 ADP320 1.520 140 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.500 1.495 1.490 100 80 60 40 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 20 1.485 –40C –5C 25C 85C 125C TJ (°C) 0 02839-009 1.480 –40 –5 25 85 125 TJ (°C) Figure 9. Output Voltage vs. Junction Temperature Figure 12. Ground Current vs. Junction Temperature, Single Output Loaded 1.510 120 100 GROUND CURRENT (µA) 1.508 VOUT (V) 1.506 1.504 80 60 40 1.502 20 1.500 100 1000 ILOAD (mA) Figure 10. Output Voltage vs. Load Current 1 1000 Figure 13. Ground Current vs. Load Current, Single Output Loaded 120 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA GROUND CURRENT (µA) 100 VOUT (V) 1.506 1.504 1.502 80 60 40 20 2.20 2.60 3.00 3.40 3.80 4.20 4.60 5.00 VIN (V) 5.40 0 1.8 02839-011 1.500 1.80 100 ILOAD (mA) 1.510 1.508 10 02839-013 10 02839-010 0 1 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 2.2 2.6 3.0 3.4 3.8 VIN (V) 4.2 4.6 5.0 5.4 02839-014 VOUT (V) 1.505 02839-012 1.510 120 GROUND CURRENT (µA) 1.515 Figure 14. Ground Current vs. Input Voltage, Single Output Loaded Figure 11. Output Voltage vs. Input Voltage Rev. 0 | Page 8 of 20 ADP320 350 120 100 250 BIAS CURRENT (µA) 200 150 100 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 50 –40 –5 25 85 60 40 125 TJ (°C) LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 20 0 02839-015 0 80 –40 –5 25 85 125 02839-018 GROUND CURRENT (µA) 300 TJ (°C) Figure 18. Bias Current vs. Junction Temperature, Single Output Loaded Figure 15. Ground Current vs. Junction Temperature, All Outputs Loaded Equally 100 300 90 80 BIAS CURRENT (µA) GROUND CURRENT (µA) 250 200 150 100 70 60 50 40 30 20 50 10 100 1000 TOTAL LOAD CURRENT (mA) 0 1 74 BIAS CURRENT (µA) 250 50 0 1.7 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 2.1 2.5 2.9 72 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 70 68 66 3.3 3.7 VIN (V) 4.1 4.5 4.9 5.3 64 2.5 02839-017 GROUND CURRENT (µA) 76 100 1000 Figure 19. Bias Current vs. Load Current, Single Output Load 300 150 100 ILOAD (mA) Figure 16. Ground Current vs. Load Current, All Outputs Loaded Equally 200 10 02839-019 10 2.9 3.3 3.7 4.1 4.5 4.9 5.3 VIN (V) Figure 17. Ground Current vs. Input Voltage, All Outputs Loaded Equally Rev. 0 | Page 9 of 20 Figure 20. Bias Current vs. Input Voltage, Single Output Load 02839-020 1 02839-016 0 ADP320 350 0.9 300 0.6 0.5 0.4 0.3 250 200 150 100 0.2 50 0.1 –25 0 25 50 75 100 0 3.10 02839-021 0 –50 125 TEMPERATURE (°C) LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 3.15 3.20 3.25 3.30 3.35 3.40 3.45 3.50 VIN (V) Figure 21. Shutdown Current vs. Temperature at Various Input Voltages 02839-024 0.7 GROUND CURRENT (µA) SHUTDOWN CURRENT (µA) 0.8 3.6 3.8 4.2 4.4 4.8 5.5 Figure 24. Ground Current vs. Input Voltage (in Dropout), VOUT1 = 3.3 V 100 300 90 250 80 200 DROPOUT (mV) DROPOUT (mV) 70 60 50 40 150 100 30 20 50 1 10 100 1000 LOAD (mA) 3.25 1000 1.85 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.80 1.75 VOUT (V) 1.70 3.15 1.65 3.10 1.60 3.05 1.55 3.00 1.50 3.15 3.20 3.25 3.30 3.35 3.40 3.45 3.50 VIN (V) 02839-023 VOUT (V) 100 LOAD (mA) 3.20 2.95 3.10 10 Figure 23. Output Voltage vs. Input Voltage (In Dropout), VOUT1 = 3.3 V 1.45 1.70 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.80 1.90 2.00 2.10 VIN (V) Figure 26. Output Voltage vs. Input Voltage (in Dropout), VOUT2 = 1.8 V Rev. 0 | Page 10 of 20 02839-026 3.30 1 Figure 25. Dropout Voltage vs. Load Current and Output Voltage, VOUT2 = 1.8 V Figure 22. Dropout Voltage vs. Load Current and Output Voltage, VOUT1 = 3.3 V 3.35 0 02839-022 0 02839-025 10 ADP320 160 0 120 –30 PSRR (dB) 100 80 60 –50 –60 LOAD = 1mA LOAD = 5mA LOAD = 10mA LOAD = 50mA LOAD = 100mA LOAD = 200mA 1.80 –90 1.90 2.00 2.10 –100 VIN (V) 10 –10 –20 1.8V/200mA 1.8V/100mA 1.8V/10mA 1.2V/200mA 1.2V/100mA 1.2V/10mA –10 –20 –40 –40 PSRR (dB) –30 –50 –60 –80 –80 –90 –100 10 –100 10 100k 1M 10M 02839-028 –90 10k 100 1k 10k 100k 1M 10 200mA 100mA 10mA 1mA 10M Figure 31. Power Supply Rejection Ratio vs. Frequency, Channel to Channel Crosstalk 0 VRIPPLE = 50mV VIN = 4.3V VOUT = 3.3V COUT = 1µF NOISE SPECTRAL DENSITY (nV/√Hz) –20 VRIPPLE = 50mV 1V HEADROOM 1.8V PSRR 1.2 XTALK FREQUENCY (Hz) Figure 28. Power Supply Rejection Ratio vs. Frequency, 1.8 V –10 10M –60 –70 FREQUENCY (Hz) 1M –50 –70 1k 100k 0 –30 100 10k Figure 30. Power Supply Rejection Ratio vs. Frequency, 1.5 V VRIPPLE = 50mV VIN = 2.8V VOUT = 1.8V COUT = 1µF 200mA 100mA 10mA 1mA 1k FREQUENCY (Hz) Figure 27. Ground Current vs. Input Voltage in Dropout), VOUT2 = 1.8 V 0 100 02839-030 0 1.70 –80 02839-031 20 –30 –40 –50 –60 –70 –80 3.3V 1.8V 1.5V 1 0.1 –100 10 100 1k 10k 100k 1M 10M FREQUENCY (Hz) 02839-029 –90 0.01 10 100 1k 10k 100k FREQUENCY (Hz) Figure 32. Output Noise Spectral Density, VIN = 5 V, ILOAD = 10 mA Figure 29. Power Supply Rejection Ratio vs. Frequency, 3.3 V Rev. 0 | Page 11 of 20 02839-032 PSRR (dB) –40 –70 40 02839-027 GROUND CURRENT (µA) 140 PSRR (dB) 200mA 100mA 10mA 1mA VRIPPLE = 50mV –10 VIN = 2.5V VOUT = 1.5V –20 COUT = 1µF ADP320 70 60 3.3V 1.8V 1.5V ILOAD2 1 NOISE (µV rms) 50 40 VOUT2 30 2 20 0.01 0.1 1 10 100 1000 LOAD CURRENT (mA) CH1 200mA Ω 02839-033 0 0.001 B W B W M40µs A CH1 84mA T 10.4% Figure 36. Load Transient Response, ILOAD2 = 1 mA to 200 mA, COUT2 = 1 μF, CH1 = ILOAD2, CH2 = VOUT2 Figure 33. Output Noise vs. Load Current and Output Voltage, VIN = 5 V ILOAD1 ILOAD3 1 2 CH2 50mV 02839-036 10 1 VOUT1 VOUT3 2 VOUT2 3 CH1 100mA Ω CH3 10mV B W B W CH2 50mV CH4 10mV B W B W M40µs A CH1 T 9.8% 44mA CH1 200mA Ω B W CH2 50mV B W M40µs A CH1 T 10.2% Figure 34. Load Transient Response, ILOAD1 = 1 mA to 200 mA, ILOAD2 = ILOAD3 = 1 mA, CH1 = ILOAD1, CH2 = VOUT1, CH3 = VOUT2 , CH4 = VOUT3 Figure 37. Load Transient Response, ILOAD3 = 1 mA to 200 mA, COUT3 = 1 μF, CH1 = ILOAD3, CH2 = VOUT3 ILOAD1 VIN 124mA 02839-037 VOUT3 02839-034 1 1 VOUT1 2 VOUT2 VOUT1 2 3 VOUT3 CH1 200mA Ω B W CH2 50mV B W M40µs A CH1 T 10.2% 124mA 02839-035 4 CH1 1V CH3 10mV B W B W CH2 10mV CH4 10mV B B W M1µs W T 15% A CH1 4.62V Figure 38. Line Transient Response, VIN = 4 V to 5 V, ILOAD1 = ILOAD2 = ILOAD3 =100 mA, CH1 = VIN, CH2 = VOUT1, CH3 = VOUT2, CH4 = VOUT3 Figure 35. Load Transient Response, ILOAD1 = 1 mA to 200 mA, COUT1 = 1 μF, CH1 = ILOAD1, CH2 = VOUT1 Rev. 0 | Page 12 of 20 02839-038 4 ADP320 VEN VIN VOUT1 1 1 VOUT1 2 VOUT2 VOUT3 VOUT2 3 VOUT3 4 B W B W CH2 10mV CH4 10mV B W B W M2µs A CH1 4.58V T 12% CH1 1V CH3 500mV Figure 39. Line Transient Response, VIN = 4 V to 5 V, ILOAD1 = ILOAD2 = ILOAD3 =1 mA, CH1 = VIN, CH2 = VOUT1, CH3 = VOUT2, CH4 = VOUT3 B W B W CH2 500mV CH4 500mV B W B W M100µs A CH1 540mV T 10.2% Figure 40. Turn On Response, ILOAD1 = ILOAD2 = ILOAD3 =100 mA, CH1 = VEN, CH2 = VOUT1, CH3 = VOUT2, CH4 = VOUT3 Rev. 0 | Page 13 of 20 02839-040 CH1 1V CH3 10mV 02839-039 2 ADP320 THEORY OF OPERATION The ADP320 triple LDO is a low quiescent current, low dropout linear regulator that operates from 1.8 V to 5.5 V on VIN1/VIN2 and VIN3 and provides up to 200 mA of current from each output. Drawing a low 250 μA quiescent current (typical) at full load makes the ADP320 triple LDO ideal for battery-operated portable equipment. Shutdown current consumption is typically 100 nA. Optimized for use with small 1 μF ceramic capacitors, the ADP320 triple LDO provides excellent transient performance. VOUT1 VIN1/VIN2 VBIAS INTERNAL BIAS VOLTAGES/CURRENTS, UVLO AND THERMAL PROTECT EN1 SHUTDOWN VOUT1 EN2 SHUTDOWN VOUT2 EN3 SHUTDOWN VOUT3 OVERCURRENT 0.5V REF VOUT2 OVERCURRENT 0.5V REF VIN3 Internally, the ADP320 triple LDO consist of a reference, three error amplifiers, three feedback voltage dividers, and three PMOS pass transistors. Output current is delivered via the PMOS pass device, which is controlled by the error amplifier. The error amplifier compares the reference voltage with the feedback voltage from the output and amplifies the difference. If the feedback voltage is lower than the reference voltage, the gate of the PMOS device is pulled lower, allowing more current to flow and increasing the output voltage. If the feedback voltage is higher than the reference voltage, the gate of the PMOS device is pulled higher, allowing less current to flow and decreasing the output voltage. The ADP320 triple LDO is available in multiple output voltage options ranging from 0.8 V to 3.3 V. The ADP320 triple LDO uses the EN1, EN2, and EN3 enable pins to enable and disable the VOUT1/VOUT2/VOUT3 pins under normal operating conditions. When the enable pins are high, VOUT1/VOUT2/ VOUT3 turn on; when enable pins are low, VOUT1/VOUT2/ VOUT3 turn off. For automatic startup, the enable pins can be tied to VBIAS. VOUT3 GND 0.5V REF 02839-041 OVERCURRENT Figure 41. Internal Block Diagram Rev. 0 | Page 14 of 20 ADP320 APPLICATIONS INFORMATION CAPACITOR SELECTION Input Bypass Capacitor Output Capacitor Connecting a 1 μF capacitor from VIN1/VIN2, VIN3, and VBIAS to GND reduces the circuit sensitivity to the PCB layout, especially when long input traces or high source impedance are encountered. If an output capacitance greater than 1 μF is required, the input capacitor should be increased to match it. The ADP320 triple LDO is designed for operation with small, space-saving ceramic capacitors, but the parts function with most commonly used capacitors as long as care is taken in regards to the effective series resistance (ESR) value. The ESR of the output capacitor affects stability of the LDO control loop. A minimum of 0.70 μF capacitance with an ESR of 1 Ω or less is recommended to ensure stability of the ADP320 triple LDO. Transient response to changes in load current is also affected by output capacitance. Using a larger value of output capacitance improves the transient response of the ADP320 triple LDO to large changes in the load current. Figure 42 show the transient response for an output capacitance value of 1 μF. ILOAD1 VOUT1 VOUT2 3 4 Any good quality ceramic capacitor may be used with the ADP320 triple LDO, as long as the capacitor meets the minimum capacitance and maximum ESR requirements. Ceramic capacitors are manufactured with a variety of dielectrics, each with a different behavior over temperature and applied voltage. Capacitors must have an adequate dielectric to ensure the minimum capacitance over the necessary temperature range and dc bias conditions. X5R or X7R dielectrics with a voltage rating of 6.3 V or 10 V are recommended. Y5V and Z5U dielectrics are not recommended, due to their poor temperature and dc bias characteristics. Figure 43 depicts the capacitance vs. voltage bias characteristic of an 0402 1 μF, 10 V, X5R capacitor. The voltage stability of a capacitor is strongly influenced by the capacitor size and voltage rating. In general, a capacitor in a larger package or higher voltage rating exhibits better stability. The temperature variation of the X5R dielectric is about ±15% over the −40°C to +85°C temperature range and is not a function of the package or voltage rating. 1 2 Input and Output Capacitor Properties VOUT3 B W CH2 50mV CH4 10mV M40µs T 9.8% A CH1 44mA 1.0 CAPACITANCE (µF) Figure 42. Output Transient Response, ILOAD1 = 1 mA to 200 mA, ILOAD2 = 1 mA, ILOAD3 = 1 mA, CH1 = ILOAD1, CH2 = VOUT1, CH3 = VOUT2 , CH4 = VOUT3 0.8 0.6 0.4 0.2 0 0 2 4 6 VOLTAGE (V) 8 Figure 43. Capacitance vs. Voltage Bias Characteristic Rev. 0 | Page 15 of 20 10 02839-043 CH1 100mA CH3 10mV B W B W 02839-042 1.2 Ω BW ADP320 As shown in Use Equation 1 to determine the worst-case capacitance accounting for capacitor variation over temperature, component tolerance, and voltage. CEFF = CBIAS × (1 − TEMPCO) × (1 − TOL) (1) where: CBIAS is the effective capacitance at the operating voltage. TEMPCO is the worst-case capacitor temperature coefficient. TOL is the worst-case component tolerance. In this example, TEMPCO over −40°C to +85°C is assumed to be 15% for an X5R dielectric. TOL is assumed to be 10%, and CBIAS is 0.94 μF at 1.8 V from the graph in Figure 43. Figure 44, the ENx pin has built-in hysteresis. This prevents on/off oscillations that can occur due to noise on the ENx pin as it passes through the threshold points. The active/inactive thresholds of the ENx pin are derived from the VBIAS voltage. Therefore, these thresholds vary with changing input voltage. Figure 45 shows typical ENx active/ inactive thresholds when the input voltage varies from 2.5 V to 5.5 V. 1.00 0.95 Substituting these values into Equation 1 yields To guarantee the performance of the ADP320 triple LDO, it is imperative that the effects of dc bias, temperature, and tolerances on the behavior of the capacitors are evaluated for each application. 0.85 0.80 VEN RISE 0.70 0.65 0.60 0.55 0.50 2.5 UNDERVOLTAGE LOCKOUT The ADP320 triple LDO has an internal undervoltage lockout circuit that disables all inputs and the output when the input voltage bias, VBIAS, is less than approximately 2.2 V. This ensures that the inputs of the ADP320 triple LDO and the output behave in a predictable manner during power-up. ENABLE FEATURE The ADP320 triple LDO uses the ENx pins to enable and disable the VOUTx pins under normal operating conditions. VEN FALL 0.75 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE (V) Figure 45. Typical ENx Pins Thresholds vs. Input Voltage The ADP320 triple LDO utilizes an internal soft start to limit the inrush current when the output is enabled. The start-up time for the 2.8 V option is approximately 220 μs from the time the ENx active threshold is crossed to when the output reaches 90% of its final value. The start-up time is somewhat dependent on the output voltage setting and increases slightly as the output voltage increases. Figure 44 shows a rising voltage on EN crossing the active threshold, then VOUTx turns on. When a falling voltage on ENx crosses the inactive threshold, VOUTx turns off. VEN VOUT1 1 1.4 VOUT2 VOUT @ 4.5VIN 1.2 VOUT3 1.0 0.6 0.4 CH1 1V CH3 500mV 0.2 0 0.5 0.6 0.7 0.8 0.9 1.0 ENABLE VOLTAGE (V) 1.1 1.2 Figure 44. Typical ENx Pin Operation Rev. 0 | Page 16 of 20 B W B W CH2 500mV CH4 500mV B W B W M100µs A CH1 540mV T 10.2% Figure 46. Typical Start-Up Time, ILOAD1 = ILOAD2 = ILOAD3 = 100 mA, CH1 = VEN, CH2 = VOUT1, CH3 = VOUT2, CH4 = VOUT3 02839-046 2 02839-054 VOUT (V) 0.8 0.4 02839-053 Therefore, the capacitor chosen in this example meets the minimum capacitance requirement of the LDO over temperature and tolerance at the chosen output voltage. ENABLE THRESHOLDS 0.90 CEFF = 0.94 μF × (1 − 0.15) × (1 − 0.1) = 0.719 μF ADP320 CURRENT-LIMIT AND THERMAL OVERLOAD PROTECTION The ADP320 triple LDO is protected against damage due to excessive power dissipation by current and thermal overload protection circuits. The ADP320 triple LDO is designed to current limit when the output load reaches 300 mA (typical). When the output load exceeds 300 mA, the output voltage is reduced to maintain a constant current limit. Thermal overload protection is built-in, which limits the junction temperature to a maximum of 155°C (typical). Under extreme conditions (that is, high ambient temperature and power dissipation) when the junction temperature starts to rise above 155°C, the output is turned off, reducing the output current to zero. When the junction temperature drops below 140°C, the output is turned on again and the output current is restored to its nominal value. Consider the case where a hard short from VOUTx to GND occurs. At first, the ADP320 triple LDO current limits, so that only 300 mA is conducted into the short. If self-heating of the junction is great enough to cause its temperature to rise above 155°C, thermal shutdown activates turning off the output and reducing the output current to zero. As the junction temperature cools and drops below 140°C, the output turns on and conducts 300 mA into the short, again causing the junction temperature to rise above 155°C. This thermal oscillation between 140°C and 154°C causes a current oscillation between 0 mA and 300 mA that continues as long as the short remains at the output. Current and thermal limit protections are intended to protect the device against accidental overload conditions. For reliable operation, device power dissipation must be externally limited so junction temperatures do not exceed 125°C. THERMAL CONSIDERATIONS In most applications, the ADP320 triple LDO does not dissipate a lot of heat due to high efficiency. However, in applications with a high ambient temperature and high supply voltage to output voltage differential, the heat dissipated in the package is large enough that it can cause the junction temperature of the die to exceed the maximum junction temperature of 125°C. When the junction temperature exceeds 155°C, the converter enters thermal shutdown. It recovers only after the junction temperature has decreased below 140°C to prevent any permanent damage. Therefore, thermal analysis for the chosen application is very important to guarantee reliable performance over all conditions. The junction temperature of the die is the sum of the ambient temperature of the environment and the temperature rise of the package due to the power dissipation, as shown in Equation 2. To guarantee reliable operation, the junction temperature of the ADP320 triple LDO must not exceed 125°C. To ensure that the junction temperature stays below this maximum value, the user needs to be aware of the parameters that contribute to junction temperature changes. These parameters include ambient temperature, power dissipation in the power device, and thermal resistances between the junction and ambient air (θJA). The θJA number is dependent on the package assembly compounds used and the amount of copper to which the GND pins of the package are soldered on the PCB. Table 6 shows typical θJA values for the ADP320 triple LDO for various PCB copper sizes. Table 6. Typical θJA Values Copper Size (mm2) JEDEC1 100 500 1000 1 ADP320 Triple LDO (°C/W) 49.5 83.7 68.5 64.7 Device soldered to JEDEC standard board. The junction temperature of the ADP320 triple LDO can be calculated from the following equation: TJ = TA + (PD × θJA) (2) where: TA is the ambient temperature. PD is the power dissipation in the die, given by PD = Σ[(VIN − VOUT) × ILOAD] + Σ(VIN × IGND) (3) where: ILOAD is the load current. IGND is the ground current. VIN and VOUT are input and output voltages, respectively. Power dissipation due to ground current is quite small and can be ignored. Therefore, the junction temperature equation simplifies to TJ = TA + {Σ[(VIN − VOUT) × ILOAD] × θJA} (4) As shown in Equation 4, for a given ambient temperature, input-to-output voltage differential, and continuous load current, there exists a minimum copper size requirement for the PCB to ensure the junction temperature does not rise above 125°C. Figure 47 to Figure 50 show junction temperature calculations for different ambient temperatures, total power dissipation, and areas of PCB copper. In cases where the board temperature is known, the thermal characterization parameter, ΨJB, may be used to estimate the junction temperature rise. TJ is calculated from TB and PD using the formula TJ = TB + (PD × ΨJB) The typical ΨJB value for the 16-lead 3 mm × 3 mm LFCSP is 25.2°C/W. Rev. 0 | Page 17 of 20 (5) 140 120 120 80 60 40 1000mm 2 500mm 2 100mm 2 50mm 2 JEDEC TJ MAX 20 0 0 0.2 0.4 0.6 0.8 1.0 80 60 40 1.2 Figure 47. Junction Temperature vs. Total Power Dissipation, TA = 25°C 0 0 120 JUCTION TEMPERATURE, TJ (°C) 120 80 60 1000mm 2 500mm 2 100mm 2 50mm 2 JEDEC TJ MAX 0 0 0.2 0.4 0.6 0.8 TOTAL POWER DISSIPATION (W) 1.0 1.2 0.6 0.8 1.0 1.2 100 80 60 40 TB = 25°C TB = 50°C TB = 85°C TJ MAX 20 0 02839-048 20 0.4 Figure 49. Junction Temperature vs. Total Power Dissipation, TA = 85°C 140 100 0.2 TOTAL POWER DISSIPATION (W) 140 40 1000mm 2 500mm 2 100mm 2 50mm 2 JEDEC TJ MAX 20 TOTAL POWER DISSIPATION (W) JUCTION TEMPERATURE, TJ (°C) 100 Figure 48. Junction Temperature vs. Total Power Dissipation, TA = 50°C Rev. 0 | Page 18 of 20 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 TOTAL POWER DISSIPATION (W) Figure 50. Junction Temperature vs. Total Power Dissipation and Board Temperature 02839-050 100 02839-049 JUCTION TEMPERATURE, TJ (°C) 140 02839-047 JUCTION TEMPERATURE, TJ (°C) ADP320 ADP320 PRINTED CIRCUIT BOARD LAYOUT CONSIDERATIONS Heat dissipation from the package can be improved by increasing the amount of copper attached to the pins of the ADP320 triple LDO. However, as can be seen from Table 6, a point of diminishing returns eventually is reached, beyond which an increase in the copper size does not yield significant heat dissipation benefits. 02839-051 Place the input capacitor as close as possible to the VINx and GND pins. Place the output capacitors as close as possible to the VOUTx and GND pins. Use 0402 or 0603 size capacitors and resistors to achieve the smallest possible footprint solution on boards where area is limited. 02839-052 Figure 51. Example of PCB Layout, Top Side Figure 52. Example of PCB Layout, Bottom Side Rev. 0 | Page 19 of 20 ADP320 OUTLINE DIMENSIONS 0.30 0.25 0.20 0.50 BSC PIN 1 INDICATOR 16 13 1 12 EXPOSED PAD 1.65 1.50 SQ 1.45 9 TOP VIEW 0.80 0.75 0.70 0.50 0.40 0.30 4 5 8 0.05 MAX 0.02 NOM COPLANARITY 0.08 0.20 REF SEATING PLANE 0.20 MIN BOTTOM VIEW FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. COMPLIANT TO JEDEC STANDARDS MO-229. 091609-A PIN 1 INDICATOR 3.10 3.00 SQ 2.90 Figure 53. 16-Lead Lead Frame Chip Scale Package [LFCSP_WQ] 3 mm × 3 mm Body, Very, Very Thin Quad (CP-16-27) Dimensions shown in millimeters ORDERING GUIDE Model 1 ADP320ACPZ331815R7 Temperature Range −40°C to +125°C Output Voltage (V) 2 3.3, 1.8, 1.5 1 Z = RoHS Compliant Part. 2 For additional voltage options, contact a local sales or distribution representative. ©2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02839-0-6/10(0) Rev. 0 | Page 20 of 20 Package Description 16-Lead LFCSP_WQ Package Option CP-16-27 Branding LGP