LP8345 Low Dropout, Low IQ, 500mA CMOS Linear Regulator General Description Features The LP8345 low-dropout CMOS linear regulator are available in 5V, 3.3V, 2.5V, 1.8V or adjustable output versions. Packaged in our 6ld LLP package and 3ld DPAK they can deliver up to 500mA output current. Typical dropout voltage @ 500mA is 210mV for the 5.0V version, 270mV for the 3.3V version and 335mV for the 2.5V version. n n n n n n n n n n The devices include a zener trimmed bandgap voltage reference, foldback current limiting and thermal overload limiting. The LP8345 features a PMOS output transistor which unlike PNP type low dropout regulators requires no base drive current. This allows the device ground current to remain less than 50µA over operating temperature, supply voltage and irrespective of the load current. ± 1.5% Typical VOUT tolerance 210mV Typical Dropout @ 500mA (VO = 5V) Wide Operating Range 2.7V to 10V Internal 500mA PMOS Output Transistor 19µA Typical Quiescent Current Thermal Overload Limiting Foldback Current Limiting Zener Trimmed Bandgap Reference Space saving LLP package Temperature Range — LP8345C 0˚C to 125˚C — LP8345I −40˚C to 125˚C Applications n n n n Hard Disk Drives Notebook Computers Battery Powered Electronics Portable Instrumentation Typical Applications Fixed VOUT 20064801 Adjustable VOUT 20064802 © 2003 National Semiconductor Corporation DS200648 www.national.com LP8345 Low Dropout, Low IQ, 500mA CMOS Linear Regulator October 2003 LP8345 Ordering Information Package 6-Pin LLP Part Number LP8345CLD-ADJ LP8345CLDX-ADJ LP8345CLD-1.8 LP8345CLDX-1.8 LP8345CLD-2.5 LP8345CLDX-2.5 LP8345CLD-3.3 LP8345CLDX-3.3 LP8345CLD-5.0 LP8345CLDX-5.0 LP8345ILD-ADJ LP8345ILDX-ADJ LP8345ILD-1.8 LP8345ILDX-1.8 LP8345ILD-2.5 LP8345ILDX-2.5 LP8345ILD-3.3 LP8345ILDX-3.3 LP8345ILD-5.0 LP8345ILDX-5.0 3-Pin DPAK LP8345CDT-1.8 LP8345CDTX-1.8 LP8345CDT-2.5 LP8345CDTX-2.5 LP8345CDT-3.3 LP8345CDTX-3.3 LP8345CDT-5.0 LP8345CDTX-5.0 LP8345IDT-1.8 LP8345IDTX-1.8 LP8345IDT-2.5 LP8345IDTX-2.5 LP8345IDTX-3.3 LP8345IDT-3.3 LP8345IDTX-5.0 LP8345IDT-5.0 www.national.com Package Marking L045B Transport Media NSC Drawing 1k Units Tape and Reel LDE06A 4.5k Units Tape and Reel 1k Units Tape and Reel L046B 4.5k Units Tape and Reel 1k Units Tape and Reel L047B 4.5k Units Tape and Reel 1k Units Tape and Reel L048B 4.5k Units Tape and Reel 1k Units Tape and Reel L049B 4.5k Units Tape and Reel 1k Units Tape and Reel L073B 4.5k Units Tape and Reel 1k Units Tape and Reel L074B 4.5k Units Tape and Reel 1k Units Tape and Reel L075B 4.5k Units Tape and Reel 1k Units Tape and Reel L076B 4.5k Units Tape and Reel 1k Units Tape and Reel L077B 4.5k Units Tape and Reel LP8345CDT-1.8 LP8345CDT-2.5 LP8345CDT-3.3 LP8345CDT-5.0 LP8345IDT-1.8 LP8345IDT-2.5 LP8345IDTX-3.3 LP8345IDTX-5.0 2 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel 75 Units/Rail 2.5k Units Tape and Reel TD03B LP8345 Connection Diagrams 6-Pin LLP ADJUSTABLE OUTPUT VOLTAGE 6-Pin LLP FIXED OUTPUT VOLTAGE 20064806 Bottom View 20064804 Bottom View Note: VIN Pins (Pin 1 & 6) must be connected together externally for full 500mA operation (250mA max per pin). VOUT Sense (Pin 5) must be connected to VOUT (Pin 4). T0-252 20064805 Top View 3 www.national.com LP8345 Absolute Maximum Ratings Human Body Model (Note 6) (Notes 1, 2kV Machine Model 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN, VOUT, VOUT Sense, ADJ −0.3V to 12V Storage Temperature Range −65˚C to 160˚C Junction Temperature (TJ) Operating Ratings(Notes 1, 2) Supply Voltage 2.7 to 10V Temperature Range LP8345C 150˚C Power Dissipation 200V 0˚C to 125˚C LP8345I (Note 3) −40˚C to 125˚C ESD Rating LP8345C Electrical Characteristics Unless otherwise specified all limits guaranteed for VIN = VO+ 1V, CIN = COUT = 10µF, TJ = 25˚C. Boldface limits apply over the full operating temperature range of TJ = 0˚C to 125˚C Symbol Parameter Conditions Min (Note 5) Typ (Note 4) Input Voltage LP8345-ADJ,1.8, 2.5 LP8345-3.3, 5.0 VOUT Output Voltage LP8345-ADJ, ADJ = OUT IOUT = 10mA, VIN = 2.7V, TJ = 25˚C 100µA ≤IOUT≤ 500mA, 2.7V ≤VIN≤VOUT +4V 1.231 1.213 1.250 1.269 1.288 V LP8345-1.8 IOUT = 10mA, VIN = 2.8V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 2.8V ≤VIN≤6V 1.773 1.746 1.800 1.827 1.854 V LP8345-2.5 IOUT = 10mA, VIN = 3.5V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 3.5V ≤VIN ≤6.5V 2.463 2.425 2.500 2.538 2.575 V LP8345-3.3 IOUT = 10mA, VIN = 4.3V TJ = 25˚C 100µA ≤IOUT ≤500mA, 4.3V ≤VIN ≤7.5V 3.250 3.201 3.300 3.350 3.399 V LP8345-5.0 IOUT = 10mA, VIN = 6V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 6V ≤VIN ≤9V 4.925 4.850 5.000 5.075 5.150 V LP8345-ADJ, ADJ=OUT IOUT = 1mA to 500mA, VIN = 2.7V 6 20 LP8345-1.8 IOUT = 1mA to 500mA, VIN = 2.8V 7 20 LP8345-2.5 IOUT = 1mA to 500mA, VIN = 3.5V 9 30 LP8345-3.3 IOUT = 1mA to 500mA, VIN = 4.3V 12 35 LP8345-5.0 IOUT = 1mA to 500mA, VIN = 6V 14 40 4 15 335 650 270 500 LP8345-5.0 IOUT = 500mA 210 400 Quiescent Current VIN ≤10V 19 50 µA Minimum Load Current VIN − VOUT ≤4V 100 µA ∆VO Load Regulation Line Regulation VIN − VO Dropout Voltage (Note 7) (Note 8) VOUT + 0.5V ≤VIN ≤10V, IOUT = 25mA (Note 7) LP8345-2.5 IOUT = 500mA LP8345-3.3 LP8345-ADJ, VOUT = 3.3V, IOUT = 500mA IQ www.national.com 4 10 10 Units VIN ∆VO 2.7 Max (Note 5) V mV mV mV (Continued) Unless otherwise specified all limits guaranteed for VIN = VO+ 1V, CIN = COUT = 10µF, TJ = 25˚C. Boldface limits apply over the full operating temperature range of TJ = 0˚C to 125˚C Symbol ILIMIT Parameter Foldback Current Limit Ripple Rejection Ratio TSD Conditions Min (Note 5) Typ (Note 4) VIN − VOUT > 5V 450 VIN − VOUT < 4V 1200 VIN (dc) = VOUT + 2V VIN (ac) = 1VP-P @ 120Hz 48 Thermal Shutdown Temp. Thermal Shutdown Hyst. mA dB 160 10 ˚C ± 0.01 ± 100 ADJ Input Leakage Current VADJ = 1.5V or 0V VOUT Leakage Current LP8345-ADJ ADJ = OUT, VOUT = 2V, VIN = 10V 10 LP8345-1.8, VOUT = 2.5V, VIN = 10V 10 LP8345-2.5, VOUT = 3.5V, VIN = 10V 10 LP8345-3.3, VOUT = 4V, VIN = 10V 10 Output Noise Units 55 LP8345-5.0, VOUT = 6V, VIN = 10V en Max (Note 5) nA µA 10 10Hz to 10kHz, RL = 1kΩ, COUT = 10µF 250 µVrms LP8345I Electrical Characteristics Unless otherwise specified all limits guaranteed for VIN = VO+ 1V, CIN = COUT = 10µF, TJ = 25˚C. Boldface limits apply over the full operating temperature range of TJ = −40˚C to 125˚C Symbol Parameter Conditions Min (Note 5) Typ (Note 4) Input Voltage LP8345-ADJ,1.8, 2.5 LP8345-3.3, 5.0 VOUT Output Voltage LP8345-ADJ, ADJ = OUT IOUT = 10mA, VIN = 2.7V, TJ = 25˚C 100µA ≤IOUT≤ 500mA, 2.7V ≤VIN≤VOUT +4V 1.231 1.213 1.250 1.269 1.288 V LP8345-1.8 IOUT = 10mA, VIN = 2.8V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 2.8V ≤VIN≤6V 1.773 1.746 1.800 1.827 1.854 V LP8345-2.5 IOUT = 10mA, VIN = 3.5V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 3.5V ≤VIN ≤6.5V 2.463 2.425 2.500 2.538 2.575 V LP8345-3.3 IOUT = 10mA, VIN = 4.3V TJ = 25˚C 100µA ≤IOUT ≤500mA, 4.3V ≤VIN ≤7.5V 3.250 3.201 3.300 3.350 3.399 V LP8345-5.0 IOUT = 10mA, VIN = 6V, TJ = 25˚C 100µA ≤IOUT ≤500mA, 6V ≤VIN ≤9V 4.925 4.850 5.000 5.075 5.150 V LP8345-ADJ, ADJ=OUT IOUT = 1mA to 500mA, VIN = 2.7V 6 20 LP8345-1.8 IOUT = 1mA to 500mA, VIN = 2.8V 7 20 LP8345-2.5 IOUT = 1mA to 500mA, VIN = 3.5V 9 30 LP8345-3.3 IOUT = 1mA to 500mA, VIN = 4.3V 12 35 LP8345-5.0 IOUT = 1mA to 500mA, VIN = 6V 14 40 Load Regulation 5 10 10 Units VIN ∆VO 2.7 Max (Note 5) V mV www.national.com LP8345 LP8345C Electrical Characteristics LP8345 LP8345I Electrical Characteristics (Continued) Unless otherwise specified all limits guaranteed for VIN = VO+ 1V, CIN = COUT = 10µF, TJ = 25˚C. Boldface limits apply over the full operating temperature range of TJ = −40˚C to 125˚C Symbol ∆VO Parameter Line Regulation VIN − VO Dropout Voltage (Note 7) (Note 8) Conditions Min (Note 5) VOUT + 0.5V ≤VIN ≤10V, IOUT = 25mA (Note 7) LP8345-2.5 IOUT = 500mA ILIMIT Units 4 15 mV 650 270 500 LP8345-5.0 IOUT = 500mA 210 400 19 Quiescent Current VIN ≤10V Minimum Load Current VIN − VOUT ≤4V Foldback Current Limit VIN − VOUT > 5V 450 VIN − VOUT < 4V 1200 Ripple Rejection Ratio TSD Max (Note 5) 335 LP8345-3.3 LP8345-ADJ, VOUT = 3.3V, IOUT = 500mA IQ Typ (Note 4) 48 VIN (dc) = VOUT + 2V VIN (ac) = 1VP-P @ 120Hz Thermal Shutdown Temp. Thermal Shutdown Hyst. 50 µA 100 µA mA 55 dB 160 10 ˚C ± 0.01 ± 100 ADJ Input Leakage Current VADJ = 1.5V or 0V VOUT Leakage Current LP8345-ADJ ADJ = OUT, VOUT = 2V, VIN = 10V 10 LP8345-1.8, VOUT = 2.5V, VIN = 10V 10 LP8345-2.5, VOUT = 3.5V, VIN = 10V 10 LP8345-3.3, VOUT = 4V, VIN = 10V 10 LP8345-5.0, VOUT = 6V, VIN = 10V en Output Noise 10Hz to 10kHz, RL = 1kΩ, COUT = 10µF mV nA µA 10 250 µVrms Note 1: Absolute Maximum ratings indicate limits beyond which damage may occur. Electrical specifications do not apply when operating the device outside of its rated operating conditions. Note 2: All voltages are with respect to the potential at the ground pin. Note 3: Maximum Power dissipation for the device is calculated using the following equations: where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θJA is the junction-to-ambient thermal resistance. The value of the θJA for the LLP package is specifically dependant on the PCB trace area, trace material, and the number of layers and thermal vias. For improved thermal resistance and power dissipation for the LLP package, refer to Application Note AN-1187. Note 4: Typical Values represent the most likely parametric norm. Note 5: All limits are guaranteed by testing or statistical analysis. Note 6: Human body model 1.5kΩ in series with 100pF. Note 7: Condition does not apply to input voltages below 2.7V since this is the minimum input operating voltage. Note 8: Dropout voltage is measured by reducing VIN until VO drops 100mV from its normal value. www.national.com 6 LP8345 Typical Performance Characteristics Unless otherwise specified, VIN = VO + 1.5V, CIN = COUT = 10µF X7R ceramic, TJ = 25˚C Output Voltage Change vs. Temperature Dropout Voltage vs. Load Current 20064807 20064808 Ground Current vs. Temperature (ILOAD = 500mA) Ground Current vs. Load Current 20064810 20064809 Ground Current vs. Input Voltage Ripple Rejection Ratio vs. Frequency 20064811 20064812 7 www.national.com LP8345 Typical Performance Characteristics (Continued) Load Transient Response Line Transient Response 20064813 20064814 Start-up Response Minimum Input Voltage Rise Time 20064815 20064819 Minimum Input Voltage Rise Time Minimum Input Voltage Rise Time 20064820 www.national.com 20064821 8 LP8345 Typical Performance Characteristics (Continued) Minimum Input Voltage Rise Time Minimum Input Voltage Rise Time 20064822 20064823 9 www.national.com LP8345 Applications Section GENERAL INFORMATION achieved by means of negative feedback to the noninverting input of the error amplifier. Feedback resistors R1 and R2 are either internal or external to the device, depending on whether it is a fixed voltage version or the adjustable version. The negative feedback and high open loop gain of the error amplifier cause the two inputs of the error amp to be virtually equal in voltage. If the output voltage changes due to load changes, the error amplifier and MOSFET driver provide the appropriate drive to the pass transistor to maintain the error amplifier’s inputs as virtually equal. The LP8345 is a low-dropout, low quiescent current linear regulator. As shown in Figure 1 it consists of a 1.25V reference, error amplifier, MOSFET driver, PMOS pass transistor and for the fixed output versions, an internal feedback network (R1/R2). In addition, the device is protected from overload by a thermal shutdown circuit and a foldback current limit circuit. The 1.25V reference is connected to the inverting input of the error amplifier. Regulation of the output voltage is 20064803 FIGURE 1. LP8345 Functional Block Diagram EXTERNAL CAPACITOR An Input capacitor of 1µF or greater is required between the LP8345 VIN pin and ground. While 1µF will provide adequate bypassing of the VIN supply larger values of input capacitor (i.e. 10µF) can provide improved bypassing of power supply noise. Stable operation can be achieved with an output capacitor of 1µF or greater, either ceramic X7R dielectric or aluminum/ tantalum electrolytic. While the minimum capacitor value is 1µF, the typical output capacitor values selected range from 1µF to 10µF. The larger values provide improved loadtransient response, power supply rejection and stability. Use the following equation to determine the values of R1 and R2 for a desired VOUT (R2 = 100Ω is recommended). MINIMUM LOAD CURRENT A minimum load of 100µA is required for regulation and stability over the entire operating temperature range. If actual load current fall below 100µA it is recommended that a resistor of value RL =VO/100µA be placed between VO and ground. OUTPUT VOLTAGE SETTING (ADJ VERSION ONLY) The output voltage is set according to the amount of negative feedback (Note that the pass transistor inverts the feedback signal). This feedback is determined by R1 and R2 with the resulting output voltage represented by the following equation: www.national.com 10 VIN−VOUT differential. The relationship between these conditions is shown in the Typical Performance Characteristics curves (Minimum Input Voltage Rise Time). VIN rise times above the curve result in < 5% overshoot. Customers are encouraged to check the suitability of LP8345 in their specific application. (Continued) START UP CONSIDERATIONS Under certain operating conditions, overshoot of VOUT at start-up can occur. The observed overshoot is a function of rise time of VIN waveform, COUT, start-up load current, and 11 www.national.com LP8345 Applications Section LP8345 Physical Dimensions inches (millimeters) unless otherwise noted 6-Pin LLP NS Package Number LDE06A 3-Pin DPAK NS Package Number TD03B www.national.com 12 LP8345 Low Dropout, Low IQ, 500mA CMOS Linear Regulator Notes LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. National Semiconductor Americas Customer Support Center Email: [email protected] Tel: 1-800-272-9959 www.national.com National Semiconductor Europe Customer Support Center Fax: +49 (0) 180-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790 National Semiconductor Asia Pacific Customer Support Center Email: [email protected] National Semiconductor Japan Customer Support Center Fax: 81-3-5639-7507 Email: [email protected] Tel: 81-3-5639-7560 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.