PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Key Features Description n Low-Dropout Regulator Supports Input Voltages Down to 1.4V n Low Dropout Voltage: 300mV@ 3A n Output Voltage Adjustable from 0.9V-3.3V n Stable with a Ceramic Output Capacitor of 1.0μF or Higher Low Quiescent Current n Current Limit n Over Temperature Shutdown n Short Circuit Current Protection n Low Temperature Coefficient n Standard TO-263 and PSOP-8 (Exposed n Pad) Packages n Pb-Free Package The PAM3131 is a 3A CMOS adjustable LDO regulator that features a low quiescent current, ultra low input, output, and dropout voltages, as well as over temperature protection. It is available in TO-263 and PSOP-8 (Exposed Pad) packages. The output voltage is adjustable from 0.9V to 3.3V. The PAM3131 is stable with a ceramic output capacitor of 1.0μF or higher. This family of regulators can provide either a stand-alone power supply solution or act as a post regulator for switch mode power supplies. They are particularly well suited for applications requiring low input and output voltages. Applications n DSP, FPGA, and Microprocessor Power Supplies n 1.2V Core Voltage for DSPs n SATA Power Supply n LCD TV/ Monitors n Wireless Devices n Communication Devices n Portable Electronics n Post Regulator for SMPS Typical Application R P 10kΩ VIN VIN EN PAM3131 C1 4.7μF GND VIN VOUT VOUT R1 EN C2 2.2μF ADJ C1 4.7μF R2 PWRGD VOUT VIN VOUT PAM3131 GND R1 C2 2.2μF ADJ R2 Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 1 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Block Diagram VOUT VIN OverCurrent Shutdown Thermal Shutdown EN AMP PWRGD ADJ Power Monitor Reference GND Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 2 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Pin Configuration & Marking Information Top View TO263-5L P3131: PAM3131 X: Internal Code Y: Year W: Week P3131 XXXYW 1 2 3 4 5 Pin Number 1 2 3 4 5 Name VIN EN GND ADJ VOUT Function Input Enable Pin Ground（Heatsink） Adjustable Pin Output Top View PSOP-8 (EPD) 8 7 6 5 P3131: PAM3131 X: Internal Code Y: Year W: Week P3131 XXXYW 1 Pin Number 1 2 3 4 5 6 7 8 2 3 4 Name GND VIN EN GND PWRGD ADJ VOUT GND Function Ground Input Enable Pin Ground Power Good Adjustable Pin Output Ground Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 3 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Absolute Maximum Ratings These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may affect device reliability. All voltages are with respect to ground. Input Voltage...............................................4.0V Output Pin Voltage.....................-0.3V to V IN +0.3V Operation Temperature Range......... -40°C to 85°C Operation Junction Temperature..... -40°C to 125°C Maximum Output Current......................P D/(V IN-V O) Storage Temperature.................... -65 °C to 150 °C Maximum Junction Temperature..................150 °C Soldering Temperature......................300 °C , 5sec Recommended Operating Conditions Supply Voltage Range.......................1.4V to 3.6V Operation Temperature Range.........-40 °C to 85 °C Junction Temperature Range......... -40 °C to 125 °C Thermal Information Parameter Thermal Resistance (Junction to Case) Thermal Resistance (Junction to Ambient) Internal Power Dissipation (@TA=25°C) Symbol θJC θJA PD Package Maximum TO-263 7 PSOP-8 10 TO-263 35 PSOP-8 50 TO-263 2800 PSOP-8 2000 Unit °C/W mW Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 4 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Electrical Characteristic V IN = V O+0.5V, T A=25 OC, C IN =4.7μF, C O=2.2μF, unless otherwise noted. Parameters Symbol Input Voltage Range VIN ADJ Reference Voltage Vref Test Conditions IO=3.0A ISC Output Current IO Quiescent Current IQ Ground Pin Current IGND MAX UNITS 3.6 V 0.9 0.918 V Vo=0.9V 330 500 Vo=1.0V 220 400 2.5V>Vo³ 1.2V 50 200 Vo³ 2.5V 40 150 Vo=0.9V 500 Vo=1.0V 400 2.5V>Vo³ 1.2V 350 Vo³ 2.5V 300 Io=100mA VDROP Short Circuit Current TYP Note 1 IO=500mA Dropout Voltage MIN 0.882 Vo < 0.3V mV 1.0 3.0 Io=0mA A Note 2 A 150 µA 1.0 mA 0.2 1.0 %/V 0.5 2 %/A 90 Io=1mA to 3.0A Vo£ 2.5V,Io=10mA Line Regulation LNR VIN =Vo+0.5V to Vo+1.5V Vo>2.5V,Io=10mA VIN =3.3V to 3.6V Load Regulation Over Temperature Shutdown Over Temperature Hysteresis Temperature Coefficient Power Supply Ripple Rejection Output Noise LDR Io=1mA to 3.0A,VIN=Vo+0.5V OTS 150 °C OTH 50 °C TC 40 ppm/°C PSRR Vn Io=100mA, Vo=1.5V f=10Hz to 100kHz f=100Hz 64 f=1kHz 58 40 dB µVrms Note1: The minimum input voltage ( V IN(MIN) ) of the PAM3131 is determined by output voltage and dropout voltage. The minimum input voltage is defined as: V IN(MIN)=V O+V drop Note 2: Output current is limited by P D , maximum I O =P D /(V IN(MAX) -V O ). Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 5 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Typical Performance Characteristics 1 1 0.9 0.9 0.8 Output Voltage(V) Output Voltage(V) T A=25 OC, C IN =4.7μF, C O=2.2μF, unless otherwise noted. 1. Output Voltage vs Input Voltage Vo=0.9V Io=10mA 0.7 0.6 Io=500mA 0.5 Io=1.5A 0.4 Vo=0.9V 0.8 0.7 Io=10mA,TA=85℃ 0.6 IO=10mA,TA=25℃ 0.5 0.4 0.3 0.3 0.8 1.2 1.6 2 2.4 2.8 3.2 0.8 3.6 1.2 1.6 Vo=1.5V 1.7 2.8 3.2 3.6 2.8 3.2 3.6 Vo=1.5V 1.7 1.5 1.5 Output Voltage(V) Output Voltage(V) 2.4 Input Voltage(V) Input Voltage(V) 1.3 1.1 Io=10mA 0.9 Io=500mA 0.7 1.3 Io=10mA,TA=25℃ 1.1 0.9 Io=10mA,TA=85℃ 0.7 Io=1.5A 0.5 0.5 0.3 0.3 0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 0.8 1.2 1.6 Input Voltage(V) 2.4 Vo=2.5V 3 Output Voltage(V) 2.5 Io=10mA 2 1.5 Io=500mA 1 2 Input Voltage(V) Vo=2.5V 3 Output Voltage(V) 2 2.5 2 Io=10mA,TA=25℃ 1.5 1 Io=10mA,TA=85℃ Io=1.5A 0.5 0.5 0.8 1.2 1.6 2 2.4 2.8 3.2 3.6 0.8 Input Voltage(V) 1.2 1.6 2 2.4 2.8 3.2 3.6 Input Voltage(V) Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 6 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Typical Performance Characteristics (continued) 2. Output Voltage vs Output Current Vo=0.9V 0.96 0.915 0.94 0.905 0.92 0.9 Output Voltage(V) Output Voltage(V) 3. Output Voltage vs Temperature Vo=0.9V,V IN=3.3V V IN=3.3V 0.88 V IN=1.5V 0.86 V IN=2.5V 0.84 Io=500mA 0.895 Io=10mA 0.885 0.875 0.865 0.82 0.8 0.855 0 500 1000 1500 2000 2500 3000 0 30 Output Current(mA) 120 150 Vo=1.5V,V IN=3.3V 1.52 1.52 1.5 1.5 Output Voltage(V) Output Voltage(V) 90 Temperature(℃) Vo=1.5V 1.54 60 V IN=3.3V 1.48 V IN=2.0V 1.46 V IN=2.5V 1.44 1.48 Io=10mA Io=500mA 1.46 1.44 1.42 1.42 1.4 1.4 0 500 1000 1500 2000 2500 0 3000 30 90 120 150 120 150 Temperature(℃) Output Current(mA) Vo=1.5V 2.56 60 Vo=2.5V,V IN=3.3V 2.55 2.5 2.52 Voltage(V) Output Voltage 2.54 2.5 2.48 V IN=3.6V 2.46 V IN=3.0V V IN=3.3V 2.44 2.45 Io=10mA Io=500mA 2.4 2.35 2.42 2.4 2.3 0 500 1000 1500 2000 2500 0 3000 30 60 90 Temperature(℃) Output Current(mA) Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 7 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Typical Performance Characteristics (continued) 5. Ground Current vs Input Voltage 140 90 120 Ground Current(uA) Quiescent Current(uA) 4. Quiescent Current vs Input Voltage 100 80 Io=0mA,TA=25℃ 70 Io=0mA,TA=85℃ 60 Io=1.5A Io=500mA 100 80 60 50 Io=10mA 40 40 20 1.8 2.1 2.4 2.7 3 3.3 1.8 3.6 2.1 2.4 2.7 3 3.3 3.6 Input Voltage(V) Input Voltage(V) 6. Ground Current vs Output Current 7. Ground Current vs Temperature 90 350 V IN =3.3V ,Io=10mA Ground Current(uA) Ground Current(uA) 300 250 200 V IN=3.3V 150 100 V IN=2.5V 50 V IN=2V 0 0 500 1000 85 80 V IN =2.5V ,Io=10mA 75 70 65 1500 2000 2500 0 3000 30 400 400 350 350 Dropout Voltage Dropout Voltage(mV) 450 Vo=2.5V Vo=0.9V 200 150 120 150 9. Dropout Voltage vs Temperature 8. Dropout Voltage vs Output Current 450 250 90 Temperature(℃) Output Current(mA) 300 60 Vo=1.5V 300 250 Vo=0.9V,Io=500mA 200 150 100 100 50 50 Vo=1.5V,Io=500mA Vo=2.5V,Io=500mA 0 0 0 500 1000 1500 2000 2500 3000 0 Output Voltage(mA) 30 60 90 120 150 Temperature(℃) Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 8 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Typical Performance Characteristics (continued) Audio Precision 12/05/06 18:30:42 11. Load Transient Response 10. Ripple Rejection vs Frequency +0 -10 -20 Io DC Coupling -30 d B -40 Vo AC Coupling Io=500mA Io=100mA -50 -60 -70 -80 10 Io=1mA 20 50 100 200 500 1k 2k 5k 10k 20k 50k 100k Hz Vo=0.9V,V IN =2.5V,Vpp=1V 12/05/06 18:24:51 Audio Precision Sweep Trace Color 1 1 1 1 +0 2 3 Line Style Thick Data Green Solid Yellow Solid Red Solid 1 1 1 Vo=1.5V,V IN=3.3V, Io=1mA to 3.0A Axis Comment Anlr.Crosstalk Left Anlr.Crosstalk Left Anlr.Crosstalk Left Io=1mA Io=100mA -10 shanghai PSRR-3 test.at1 -20 Io DC Coupling -30 d B Io=500mA -40 Io=100mA Vo AC Coupling -50 -60 Io=1mA -70 -80 10 20 50 100 200 500 1k 2k 5k 10k 20k 50k 100k Hz Audio Precision Sweep Trace 1 1 1 1 +0 2 3 Vo=1.5V,V IN =2.5V,Vpp=1V Line Style Thick Data Axis Comment12/05/06 18:37:46 Vo=1.5V,V IN=3.3V, Io=1mA to 1.0A Color Blue Solid Cyan Solid Green Solid -10 1 1 1 Anlr.Crosstalk Left Anlr.Crosstalk Left Anlr.Crosstalk Left Io=1mA Io=100mA Io=500mA shanghai PSRR-3 test.at1 Io DC Coupling -20 -30 d B Io=500mA Io=100mA -40 Vo AC Coupling -50 -60 Io=1mA -70 -80 10 20 50 100 200 500 1k 2k 5k 10k 20k 50k 100k Hz Vo=2.5V,V IN=3.3V,Vpp=0.3V Sweep Trace Color 1 2 3 1 1 1 Line Style Thick Data Magenta Solid Blue Solid Cyan Solid 1 1 1 Vo=1.5V,V IN=3.3V, Io=1A to 3.0A Axis Comment Anlr.Crosstalk Left Anlr.Crosstalk Left Anlr.Crosstalk Left Io=1mA Io=100mA Io=500mA shanghai PSRR-3 test.at1 Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 9 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Typical Performance Characteristics (continued) 12. Line Transient Response V IN DC Coupling Vo AC Coupling Vo=1.5V,Io=100mA, V IN =2.0V to 3.3V Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 10 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Application Information T h e PA M 3 1 3 1 f a m i l y o f l o w - d r o p o u t ( L D O ) regulators have several features that allow them to apply to a wide range of applications. The family operates with very low input voltage (1.4V) and low dropout voltage (typically 300mV at full load), making it an efficient stand-alone power supply or post regulator for battery or switch mode power supplies. The 3A output current make the PAM3131 family suitable for powering many microprocessors and FPGA supplies. The PAM3131 family also has low output noise (typically 40µVRMS with 2.2µF output capacitor), making it ideal for use in telecom equipment. increasing R1+R2 will reduce stability. In general, R1 and R2 in the 10’s of kΩ will produce adequate stability, given reasonable layout p r e c a u t i o n s . To i m p r o v e s t a b i l i t y characteristics, keep parasitics on the ADJ pin to a minimum, and lower R1 and R2 values. Thermal Information The amount of heat that an LDO linear regulator generates is: P D =(V IN -V O )I O . All integrated circuits have a maximum allowable junction temperature (T J max) above which normal operation is not assured. A system designer must design the operating environment so that the operating junction temperature (T J ) does not exceed the maximum junction temperature (T J max). The two main environmental variables that a designer can use to improve thermal performance are air flow and external heatsinks. The purpose of this information is to aid the designer in determining the proper operating environment for a linear regulator that is operating at a specific power level. External Capacitor Requirements A 2.2µF or larger ceramic input bypass capacitor, connected between V IN and GND and located close to the PAM3131, is required for stability. A 1.0μF minimum value capacitor from V O to GND is also required. To improve transient response, noise rejection, and ripple rejection, an additional 10µF or larger, low ESR capacitor is recommended at the output. A higher value, low ESR output capacitor may be necessary if large, fast-rise-time load transients are anticipated and the device is located several inches from the power source, especially if the minimum input voltage of 1.4V is used. In general, the maximum expected power (P D(max)) consumed by a linear regulator is computed as: Regulator Protection PDmax= ( VI ( avg)( -VO avg) ×IO ( avg)( +VI avg) ×I ( Q) ) (1) The PAM3131 features internal current limiting, thermal protection and short circuit protection. During normal operation, the PAM3131 limits output current to about 4.5A. When current limiting engages, the output voltage scales back linearly until the over current condition ends. While current limiting is designed to prevent gross device failure, care should be taken not to exceed the power dissipation ratings of the package. If the temperature of the device exceeds 150°C, thermalprotection circuitry will shut down. Once the device has cooled down to approximately 50°C below the high temp trip point, regulator operation resumes. The short circuit current of the PAM3131 is about 1A when its output pin is shorted to ground. Where: l V I (avg) is the average input voltage. l V O(avg) is the average output voltage. l I O(avg) is the average output current. l I (Q) is the quiescent current. For most LDO regulators, the quiescent current is insignificant compared to the average output current; therefore, the term V I(avg) xI (Q) can be neglected. The operating junction temperature is computed by adding the ambient temperature (T A) and the increase in temperature due to the regulator' s power dissipation. The temperature rise is computed by multiplying the maximum expected power dissipation by the sum of the thermal resistances between the junction and the case (R θJC), the case to heatsink (R θCS ), and t h e h e a t s i n k t o a m b i e n t ( R θSA) . T h e r m a l resistances are measures of how effectively an object dissipates heat. Typically, the larger the device, the more surface area available for power dissipation so that the object 's thermal resistance will be lower. Output Adjustment The PAM3131 uses external feedback resistors to generate an output voltage from 0.9V to 3.3V. V adj is trimmed to 0.9V and V OUT is given by the equation: V OUT = V adj ( 1 + R1 / R2 ) Feedback resistors R1 and R2 should be high enough to keep quiescent current low, but Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 11 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Ordering Information PAM3131 X X X X Packing Number of Pins Package Type Pin Configuration Pin Configuration A Type 1. VIN Package Type Number of Pins M: TO-263 B: 5 E: PSOP C: 8 2. EN 3. GND 4. ADJ 5. VOUT B Type 1. GND 2. VIN 3. EN 4. GND 5. PWRGD 6. ADJ 7. VOUT 8. GND Part Number Package Type Standard Package PAM3131AMBR TO263-5L 800 Units/Tape&Reel PAM3131BECR PSOP-8 2,500 Units/Tape&Reel Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 12 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Outline Dimension TO263-5L A c2 L D L2 E L4 L1 c e b θ Dimensions(Millimeter) Symbol MIN NOM MAX A 4.40 4.60 4.80 b 0.66 0.78 0.91 L4 0.00 0.15 0.30 c 0.36 0.43 0.50 L3 1.50 REF. L1 2.29 2.54 2.79 E 9.80 10.1 10.4 c2 1.25 1.35 1.45 L2 1.27 REF. D 8.6 8.8 9.0 e 1.70 REF. L 14.6 15.2 15.8 θ 0º 4º 8º Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 13 PAM3131 3A Adjustable Low Voltage Low Dropout CMOS Regulator Outline Dimension PSOP-8 Power Analog Microelectronics,Inc www.poweranalog.com 10/2010 Rev1.1 14