Low Dropout Voltage Regulator

www.DataSheet4U.com SPX2815 1.5A Low Dropout Voltage Regulator FEATURES ■ Guaranteed 1.5A Output Current ■ Three Terminal Adjustable or Fixed 2.5V, 3.3V and 5.0V ■ Low Quiescent Current ■ Low Dropout Voltage of 1.1V @ 1.5A ■ 0.1% Line and 0.1% Load Regulation ■ Stable with 10uF Ceramic Capacitor ■ Overcurrent and Thermal Protection ■ Available Packages: TO-252, TO-220, and TO-263 ■ Similar to Industry Standard LT1086/ LT1586 APPLICATIONS ■ Desktop PCs, Servers ■ Powering VGA and Sound Cards ■ Cordless Phones ■ Battery Chargers ■ Adjustable Power Supplies ■ Portable Instrumentation ■ SMPS Post-Regulator ■ Constant Current Regulators ■ Disk Drives Refer to Page 5 for Pinouts Now Available in Lead Free Packaging DESCRIPTION The SPX2815 is a low power positive-voltage regulator designed to satisfy moderate power requirements with a cost effective, small footprint solution. This device is an excellent choice for use in battery-powered applications and portable computers. The SPX2815 features very low quiescent current and a low dropout voltage of 1.1V at a full load. As output current decreases, quiescent current flows into the load, increasing efficiency. SPX2815 is available in adjustable or fixed 2.5V, 3.3V and 5.0V output voltages. The SPX2815 is offered in several 3-pin surface mount packages: TO-252, TO-220 and TO-263. An output capacitor of 10μF ceramic or tantalum provides unconditional stability. FUNCTIONAL DIAGRAM (Adjustable) VIN Current Limit + VOUT ICL _ AMP + 1.25V Thermal Limit + – VREF ADJ/GND IADJ ~ 50μA – I TL Date: 6/21/06 Rev C SPX2815 1.5A Low Dropout Voltage Regulator © 2006 Sipex Corporation 1 ABSOLUTE MAXIMUM RATINGS Power Dissipation.......................................Internally Limited Lead Temperature (soldering, 5 seconds) ...............260°C Storage Temperature Range.......................-65°C to +150°C Operating Junction Temperature Range.....-40°C to +125°C Input Supply Voltage .................................................... +10V Input to Output Voltage ................................................ +8.8V ESD Rating .............................................................. 2kV min ELECTRICAL CHARACTERISTICS at VIN=VOUT + 1.5V, TA = 25°C, CIN = COUT = 10μF, IOUT =10mA, unless otherwise specified. The Boldface applies over the full operating temperature range. PARAMETER 2.5V Version Output Voltage 3.30V Version Output Voltage 5.0V Version Output Voltage All Voltage Options Reference Voltage Output Voltage Temperature Stability Line Regulation 1.238 1.250 1.225 0.3 0.1 0.1 0.1 0.1 0.1 0.1 1.00 1.10 4 50 2.5 0.01 60 75 0.03 0.003 3 29.3 3 31.4 6 50 0.1 60 0.2 0.2 0.2 0.3 0.3 0.3 1.2 10 120 2.5 0.01 75 0.03 0.003 3 29.3 3 31.4 6 50 0.1 1.262 1.225 1.250 1.275 1.212 0.5 0.1 0.1 0.1 0.1 0.1 0.1 1.00 1.10 4 50 0.2 0.2 0.2 0.3 0.3 0.3 1.2 10 120 mA μA A %/W dB % % °C/W (VIN-VOUT)=5V 25°C, 30mS pulse fRIPPLE=120Hz, (VIN-VOUT)=2V, VRIPPLE=1VPP 125°C, 1000Hrs % of VOUT, 10Hz≤f≤10kHz TO-220 Junction to Case, at Tab TO-220 Junction to Ambient TO-263 Junction to Case, at Tab TO-263 Junction to Ambient TO-252 Junction to Case, at Tab TO-252 Junction to Ambient 1.275 1.287 V % % 4.25V≤VIN≤ 10V,VOUT=2.5V,IOUT=10mA 4.75V≤VIN≤ 10V,VOUT=3.3V,IOUT=10mA 6.50V≤VIN≤ 10V,VOUT=5.0V,IOUT=10mA 10mA≤IOUT≤ 1.5A, VOUT=2.5V 10mA≤IOUT≤ 1.5A, VOUT=3.3V 10mA≤IOUT≤ 1.5A, VOUT=5.0V IOUT=0.5A IOUT=1.5A Fixed voltage versions IOUT=10mA, (VIN - VOUT )= 2V 10mA≤IOUT≤ 1.5A, 1.5V≤(VIN-VOUT)≤ 10V 4.950 5.000 4.900 5.050 4.900 5.000 5.100 4.850 5.100 5.150 V IOUT=10mA, VIN=7V 10mA ≤ IOUT ≤ 1.5A, 6.50V ≤ VIN ≤ 10V 3.267 3.300 3.234 3.333 3.234 3.300 3.366 3.201 3.366 3.399 V IOUT = 10mA, VIN =5V 10mA ≤ IOUT ≤ 1.5A, 4.75V ≤ VIN ≤ 10V MIN TYP SPX2815A 2.475 2.500 2.450 MAX MIN TYP SPX2815 2.525 2.450 2.500 2.550 2.425 2.550 2.575 V IOUT = 10mA, VIN =4.5V 10mA ≤ IOUT ≤ 1.5A, 4.25V ≤ VIN ≤ 10V MAX UNITS CONDITIONS Load Regulation % Dropout Voltage (Note 2) Quiescent Current Adjust Pin Current Current Limit Thermal Regulation Ripple Rejection Long Term Stability RMS Output Noise Thermal Resistance V Date: 6/21/06 Rev C SPX2815 1.5A Low Dropout Voltage Regulator © 2006 Sipex Corporation 2 TYPICAL PERFORMANCE CHARACTERISTICS 3.325 3.320 1.275 1.27 1.265 1.26 1.255 1.25 1.245 1.24 1.235 1.23 1.225 -50 1.25v Adj Vout (V) 3.315 3.310 3.305 3.300 4.5 6.5 8.5 10.5 Vin (V) 12.5 14.5 Vout (V) -30 -10 10 30 50 70 90 110 130 Temp (C) Figure 1. Line Regulation for SPX2815U-3.3; IOUT=10mA Figure 2. VOUT vs Temperature, VIN=2.5V, IOUT=10mA 2.55 2.54 2.53 2.52 2.51 2.5 2.49 2.48 2.47 2.46 2.45 -50 3.38 2.5v Adj 2.5v Fixed 3.36 3.34 Vout (V) 3.3v Adj 3.3v Fixed Vout (V) 3.32 3.3 3.28 -30 -10 10 30 50 Temp (C) 70 90 110 130 3.26 -50 -30 -10 10 30 50 70 90 110 130 Temp (C) Figure 3. VIN=4.0V, IOUT=10mA Figure 4. VIN=5.0V, IOUT=10mA APPLICATION INFORMATION Output Capacitor To ensure the stability of the SPX2815, an output capacitor of at least 10μF (ceramic or tantalum) or 22μF (aluminum) is required. The value may change based on the application requirements of the output load or temperature range. The value of Equivalent Series Resistance (ESR) can vary based on the type of capacitor used in the applications to guarantee stability. The recommended value for ESR is 0.5Ω or less. A larger value of output capacitance (up to 100μF) can improve the load transient response. Soldering Methods tions. Special care needs to be taken during continuous load conditions such that the maximum junction temperature does not exceed 125°C. Thermal protection is activated at >179°C and deactiviated at <165°C. The thermal interaction from other components in the application can affect the thermal resistance of the SPX2815. The actual thermal resistance can be determined with experimentation. SPX2815 power dissipation is calculated as follows: PD = (VIN - VOUT)(IOUT) Maximum Junction Temperature range: TJ = TA(max) + PD* θJA (thermal resistance, junction-to-ambient) Maximum junction temperature must not exceed 125°C. The SPX2815 die is attached to the heatsink lead which exits opposite the input, output, and ground pins. Thermal Characteristics The SPX2815 features internal thermal limiting to protect the device during overload condi- Date: 6/21/06 Rev C SPX2815 1.5A Low Dropout Voltage Regulator © 2006 Sipex Corporation 3 APPLICATION INFORMATION: Continued Ripple Rejection Ripple rejection can be improved by adding a capacitor between the ADJ pin and ground as shown in Figure 8. When ADJ pin bypassing is used, the value of the output capacitor required increases to its maximum. If the ADJ pin is not bypassed, the value of the output capacitor can be lowered to 22μF for an electrolytic aluminum capacitor or 10μF for a solid tantalum capacitor (Fig 7). However, the value of the ADJ-bypass capacitor should be chosen with respect to the following equation: Ripple rejection for the adjustable version is shown in Figure 5. Output Voltage The output of the adjustable regulator can be set to any voltage between 1.25V and 15V. The value of VOUT can be quickly approximated using the formula VOUT=1.25 *(R1 + R2)/R1 A small correction to this formula is required depending on the values of resistors R1 and R2, since the adjustable pin current (approx 50μA) flows through R2. When IADJ is taken into account, the formula becomes VOUT = VREF(1+ (R2/R1)) + IADJ * R2 where VREF=1.25V C= _______1______-_ ( 6.28 * FR * R1 ) Where C = value of the capacitor in Farads (select an equal or larger standard value), FR = ripple frequency in Hz, R1 = value of resistor R1 in Ohms. If an ADJ-bypass capacitor is used, the amplitude of the output ripple will be independent of the output voltage. If an ADJ-bypass capacitor is not used, the output ripple will be proportional to the ratio of the output voltage to the reference voltage: M = VOUT / VREF Where M = multiplier for the ripple seen when the ADJ pin is optimally bypassed. VREF =1.25V Layout Considerations Parasitic line resistance can degrade load regulation. In order to avoid this, connect R1 directly to VOUT as illustrated in Figure 13. For the same reason, R2 should be connected to the negative side of the load. 0 -10 -20 -30 -40 -50 -60 -70 -80 -90 10 100 1000 10000 100000 1000000 Frequency, Hz Ripple Rejection, Db V IN 4.7μF + C1 IN SPX2815 ADJ OUT C2 R1 VOUT IOUT = VREF R1 IOUT LOAD Figure 5. Ripple Rejection; Vin=3.3V, Vout=1.8V (adj.), Iload=200mA Figure 6. Current Source Date: 6/21/06 Rev C SPX2815 1.5A Low Dropout Voltage Regulator © 2006 Sipex Corporation 4 APPLICATION INFORMATION: Continued (Note A) V IN SPX2815 IN OUT 5V VOUT R1 330Ω 1% 10μF VIN 4.7μF + C1 IN SPX2815 ADJ I ADJ 50μA OUT C2 VREF R1 VOUT + 4.7μF ADJ VOUT = V REF (1+R 2 /R1 ) +I ADJ R 2 R2 *C 1 improves ripple rejection. ZC should be ~ R1 at ripple frequency R2 1kΩ, 1% + C1 10μF* Note A: VIN(MIN) = (Intended VOUT ) + (V DROPOUT (MAX) ) Figure 7. Typical Adjustable Regulator Figure 8. Improving Ripple Rejection SPX2815 VIN (Note A) ADJ IN OUT 5V 330W 1% + R P Parasitic Line Resistance VIN SPX2815 VOUT + 4.7μF TTL Input 1K 2N3904 1k ADJ 10μF Connect R to Case of Regulator 1kΩ 1% R1 Connect R2 to Load RL R2 Note A: VIN(MIN) = (Intended VOUT ) + (V ) DROPOUT (MAX) Figure 9. 5V Regulator with Shutdown Figure 10. Recommended Connections for Best Results PINOUTS TO-252 (R) TO-220-3 (U) TO-263-3 (T) 1 2 3 1 2 3 1 2 3 ADJ/GND V OUT V IN ADJ/GND V OUT V IN Front View ADJ/GND V OUT V IN Top View Front View Note: Tab is connected to Pin 2 (Vout) Date: 6/21/06 Rev C SPX2815 1.5A Low Dropout Voltage Regulator © 2006 Sipex Corporation 5 PACKAGE: 3 PIN TO-263 E A E/2 L1 C2 Seating Plane SIDE VIEW H D Chamfer Optional 1 2 3 c e See Detail C b2 b Gauge Plane FRONT VIEW θ L3 A1