LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET KEY FEATURES DESCRIPTION Accurate Output Voltage Typical Dropout of 1.2V at 1A and 1.1V at 500mA Independent Thermal and Current Limit Protection Low Profile 3 Lead SMT Power Package Low Tolerance Load Regulation (0.4%) Wide DC Supply Voltage of 4.3V to 10V Loop Stability Independent of Output Capacitor Type bs ol et e The LX8818 features on-chip trimming of the internal voltage enabling precise output voltages, typically ±1% of it’s specified value, while the BiPolar output transistor has a low dropout voltage even at full output current (VDO < 1.2V typ. @ 1A). Output voltage overshoot is minimized when VIN is applied, typically VOUT overshoot < 2% for VIN ≤ 1V/uS ramp. Thermal and Short Circuit Current Protection are integrated on-chip. Microsemi’s D-PAK or Micro power package enables maximum power dissipation and ease of assembly using surface mount technology. WWW . Microsemi .C OM The LX8818 is a single channel positive-voltage linear regulator. The regulator output is configured as fixed (3.3v or 2.5v) or adjustable, featuring low-dropout and high accuracy. The LX8818 regulator is stable with ceramic or tantalum low-value capacitors, typically 2.2µF on the outputs, allowing designers flexibility in external component selection. The LX8818 provides designers with a flexible power management solution. The regulator design is optimized for system efficiency by consuming minimal ground current and directing quiescent current to the load. APPLICATIONS/BENEFITS IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com 5V to 3.3V/2.5V Regulators Hard Disk Drives, CD-ROMs ADSL and Cable Modems Battery Charging Circuits Instrumentation PC Peripherals APPLICATION CIRCUITS Fixed Output Adjustable Output VIN = 5V VIN = 5V VIN VOUT 3.3V @ 1.0A VOUT LX8818-0x 4.7µF 1.8V* @ 1.0A R1 499 4.7µF ADJ 4.7µF GND GND R2 1150 ⎛ R1 ⎞ *V1 = VREF⎜⎜1+ ⎟ + I ADJR1 ⎝ R2 ⎠ LX8818 O 4.7µF VIN LX8818-0x PACKAGE ORDER INFO TJ (°C) OUTPUT V 0 to 125 3.3V LM Plastic MLP 6-PIN RoHS Compliant / Pb-free Transition DC: 0452 LX8818-02CLM MLP Part Marking DT 8-02 Plastic TO-252 3-PIN LX8818-01CDT Consult Factory for 2.5V and Adjustable Versions Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX8818-01CDT-TR) Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 1 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION PACKAGE PIN OUT Input Voltage (VIN) .................................................................................................... 13.5V Load Current (Internally Limited)................................................................................... 1A Power Dissipation ................................................................................... Internally Limited Short-Circuit Protection ........................................................................................Indefinite Operating Junction Temperature................................................................................ 150°C Lead Temperature (Soldering 180 seconds)............................................................... 235°C RoHS Peak Package Solder Reflow Temperature (40 seconds maximum exposure)..................................................................260°C (+0, -5) VIN GND bs ol et e Note: TAB is GND Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal. VOUT DT PACKAGE WWW . Microsemi .C OM ABSOLUTE MAXIMUM RATINGS DATA SHEET (Top View) THERMAL DATA DT Plastic D-Pak 3-Pin * THERMAL RESISTANCE-JUNCTION TO TAB, θJT THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 6°C/W ADJ 1 6 GND 25-35°C/W VOUT 2 5 N/C VIN 3 4 N/C (TYPICAL, DEPENDING ON MOUNTING/PCB LAYOUT) LM Plastic MLP 6-Pin * 8°C/W THERMAL RESISTANCE-JUNCTION TO TAB, θJT LM PACKAGE THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA 29-35°C/W (TYPICAL, DEPENDING ON MOUNTING/PCB LAYOUT) Junction Temperature Calculation: TJ = TA + (PD x θJA). The θJA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. θJA can vary significantly depending on mounting technique. (See Application Notes Section: Thermal considerations) (Top View) * Must be connected to GND or left floating (see pg 8 for details) RoHS / Pb-free 100% Matte Tin Lead Finish N/C = Not internally connected FUNCTIONAL PIN DESCRIPTION DESCRIPTION O PIN NAME VIN GND VOUT Adjustable version only. The output voltage can be set by two external resistors with the following relationship: VOUT = VREF * (1+ (R1/R2)) + (IADJ * R1) where R1 is the resistor connected between VOUT and ADJ, and R2 is the resistor connected between ADJ and GND (see figure 2 on page 7). Common terminal for ground reference. The input and output bypass capacitors should be connected to this pin. In addition the tab on the “DT” package is also used for heat sinking the device. Regulator output. It is recommended to bypass to GND with at least 2.2uF. Size your output capacitor to meet the transient loading requirement. If you have a very dynamic load, a lower ESR capacitor will improve the response to these load steps. Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 2 PACKAGE DATA ADJ Positive unregulated supply input for the regulator. Bypass to GND with at least 2.2µF of low ESR and ESL capacitance. LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET Parameter Symbol Input Voltage VIN Min LX8818-0x Typ Units Max 10 V VOUT 5.5 V Load Current (with adequate heat sinking) IL 1000 mA Operating Junction Temperature TJ 125 °C 4.5 bs ol et e Output Voltage (adjustable) ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C ≤ TA ≤ 125°C except where otherwise noted and the following test conditions: VIN = 5V, IOUT = 10mA, C1= 10µF (Tantalum), C2= 4.7µF (Tant.), & TJ = TA using low duty cycling methods. LX8818-0x Parameter Symbol Test Conditions Units Min Typ Max ` Fixed Output (3.3V) Output Voltage VOUT 3.250 3.300 3.353 V .0065 V/V(Vin) ∆VOUT(VIN) 4.75V < VIN < 10V, IOUT = 5mA .0042 Load Regulation ∆VOUT(IOUT) 5mA < IOUT < 1A, VIN = 4.75V 4 7 mV ILOAD = 1A, ∆VOUT = -1% 1.25 1.33 V ILOAD = 0.5A, ∆VOUT = -1% 1.12 1.18 V 0 mA 2.500 2.539 V .0042 .0065 V/V(Vin) ∆V Current Limit IOUT (MAX) Minimum Load Current IL 1.0 Note 1 1.32 0 A Fixed Output (2.5V) Output Voltage VOUT Line Regulation ∆VOUT(VIN) 4.75V < VIN < 10V, IOUT = 5mA Load Regulation ∆VOUT(IOUT) 5mA < IOUT < 1A, VIN = 4.75V ∆V Dropout Voltage (PWR) Current Limit 5mA < IOUT < 1A, 4.75V < VIN < 7V O IL 2.469 4 6 mV ILOAD = 1A, ∆VOUT = -1% 1.25 1.30 V ILOAD = 0.5A, ∆VOUT = -1% 1.12 1.15 IOUT (MAX) Minimum Load Current ` 5mA < IOUT < 1A, 4.75V < VIN < 7V Line Regulation Dropout Voltage (PWR) ` WWW . Microsemi .C OM RECOMMENDED MAX OPERATING CONDITIONS 1.0 Note 1 1.32 A 0 0 mA 1.250 1.266 V Adjustable Output Reference Voltage VREF 5mA < IOUT < 1A, 4.75V < VIN < 7V 1.234 ∆VOUT(VIN) 4.5V < VIN < 10V, IOUT = 5mA .06 .075 %/VOUT Load Regulation ∆VOUT(IOUT) 5mA < IOUT < 1A, VIN = 4.75V .14 0.2 %/VOUT ILOAD = 1A, ∆VOUT = -1% 1.25 1.30 V ILOAD = 0.5A, ∆VOUT = -1% 1.12 1.15 ILOAD = 5mA, ∆VOUT = -1% 1.0 1.02 Dropout Voltage (PWR) Current Limit ∆V IOUT (MAX) Minimum Load Current IL Adjust Pin Bias Current IADJ 1.0 Note 1 1.32 A 0 5 mA 0.05 0.5 µA Note 1: Minimum load current is defined as the amount of output current required to maintain regulation. Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 3 ELECTRICALS Line Regulation LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET ` Entire Regulator Quiescent Current IQ PSRR VIN < 7V f=120Hz, VIN = 5V 2.56 60 3.5 75 bs ol et e Ripple Rejection RMS Output Noise (% of VOUT) Thermal Shutdown VOUT (RMS) TJSD 10Hz < f < 10kHz 5mA < IOUT < 1A, VIN = 4.75V 135 mA DB 0.003 %/V 140 °C WWW . Microsemi .C OM ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature 0°C ≤ TA ≤ 125°C except where otherwise noted and the following test conditions: VIN = 5V, IOUT = 10mA, C1= 10µF (Tantalum), C2= 4.7µF (Tant.), & TJ = TA using low duty cycling methods. LX8818-0x Parameter Symbol Test Conditions Units Min Typ Max Copyright © 2000 Rev. 1.0a, 2005-03-14 ELECTRICALS O Note 1: Minimum load current is defined as the amount of output current required to maintain regulation. Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 4 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET WWW . Microsemi .C OM BLOCK DIAGRAM V IN C1 10µF V OUT BIAS C2 4.7µF bs ol et e + - 1.25V V REF GND Note: Application circuit above using ceramic capacitors. Figure 1 – Fixed Output V IN C1 10µF V OUT BIAS C2 4.7µF + - R1 O ADJ R2 1.25V V REF BLOCK DIAGRAM ⎛ R1 ⎞ VOUT = VREF × ⎜1 + ⎟ + IADJ × R1//R2 ⎝ R2 ⎠ GND Note: Application circuit above using ceramic capacitors. Figure 2 – Adjustable Output (R1/R2 can be selected to satisfy the minimum load requirements) Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 5 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET CHARACTERISTIC CURVES WWW . Microsemi .C OM STEP LOAD STABILITY OUTPUT VOLTAGE TEMPERATURE STABILITY T Vout vs Temp 2 Vout bs ol et e 3.32 3.315 3.31 3.305 3.3 3.295 3.29 3.285 3.28 3.275 3.27 -75 4 -50 -25 0 25 50 75 100 125 150 Temp, °C CH2 50.0mV~ CH4 500mAΩ B W M 10.0µs T 11.80% A CH4 610mA CH2: Vout, CH4: Istep, Cin = Cout = 10µF Ceramic, Load Current, dc = 5mAVdroop=150mV SUPPLY VOLTAGE, FAST TURN ON (Trise = 10uS) SHORT CIRCUIT AND RECOVERY CH1: Vout, CH4: Istep, Cin = Cout = 10µF Ceramic T 1 4 2 CH1 2.00V CH2 1.00V M 100µs T A CH1 3.64V CH1: Vin, CH2: Vout, Cin = Cout = 10µF Ceramic, Load Current, dc = 5mA Copyright © 2000 Rev. 1.0a, 2005-03-14 CH1 2.00V M CH4 288.8µs 4.00 s A CH1 3.92V 500mAΩ CH1: Vout, CH4: Iout, Cin = Cout = 10µF Ceramic Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 6 CHARTS O 1 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET Description Temperature Protection The LX8818 is part of a family of LDO (Low Drop-Out) linear regulators in the TO-252 or MO229 packages which offer maximum power dissipation in a low profile surface mount technology. The family includes either fixed or adjustable output versions. The output can supply up to one amp with a regulator design optimized for system efficiency by consuming minimal ground current and directing quiescent current to the load. The thermal protection shuts the LX8818 down when the junction temperature exceeds 1400C. Exposure to absolute maximum rated conditions for extended periods may affect device reliability (see Thermal Considerations below). Current Limit Protection bs ol et e The LX8818 includes over current protection. When the output load current exceeds typically 1.4A, the circuit forces the regulator output to decrease. Input Capacitor To improve load transient response and noise rejection an input bypass capacitor of at least 10uF is required. Generally we recommend a 10uF ceramic or tantalum or 22uF electrolytic capacitor. Output Capacitor The regulator requires an output capacitor connected between VOUT to GND to stabilize the internal control loop. Many types of capacitors are available, with different capacitance values tolerances, temperature coefficients and equivalent series resistance. We recommend a minimum of 4.7uF. To ensure good transient response from the power supply system under rapidly changing current load conditions, designers generally use additional output capacitors connected in parallel. Such an arrangement serves to minimize the effects of the parasitic resistance (ESR) and inductance (ESL) that are present in all capacitors. The regulator has been tested stable with capacitor ESR’s in the range of 0.05 to 2 ohms. We have found it best to use the same type of capacitor for both input and output bypass. Adjustable Output Voltage ADJ TJUNCTION = TJUNCTION-TAB RISE _+ TTAB-AMB RISE + TAMB TTAB = PD MAX * θJT ; TTAB-AMB = PD REG * θPCB = (5V-3.3V) * (200mA) * 6°C/W = (440mW) * 6°C/W = 2.6°C TTAB-AMB RISE = ( 440mW ) * 32°C/W = 14.1°C TJUNCTION = 2.6°C + 14.1°C + 50°C = 66.7°C R2 Minimum Load Requirement The LX8818 has a minimum load requirement for proper output regulation. This minimum current is specified at 0mA for the fixed output and 5ma for the adjustable output. It is important to note that although each output of the regulator will produce up to 1A in current, the individual or total power dissipation may limit the useful total current draw. The junction temperature should be calculated for each individual output as well as the combined outputs to insure the maximum junction temperature in not exceeded. Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 7 APPLICATIONS VREF For the D-PAK package, thermal resistance, θTAB-AMB is 25-450C/W depending on mounting technique when mounted on a FR4 copper clad PCB. Junction temperature of the integrated circuit can be calculated using: TJ-TAB REG FIGURE 2 - BASIC ADJUSTABLE REGULATOR Copyright © 2000 Rev. 1.0a, 2005-03-14 PD = (VIN(MAX)-Vout) * Iout Calculated values: R1 IADJ 1µA ⎛ R1 ⎞ ⎟ + I ADJ R1 Vout = V REF ⎜1 + ⎜ R 2 ⎟⎠ ⎝ Power dissipation for regulator can be calculated using the following equation: An example: Given conditions: TA = 50°C, VIN= 5.0V, Vout= 3.3V, Iout= 200mA. Vout O LX8818-0x Thermal shutdown protects the integrated circuit from thermal overload caused from a rise in junction temperature during power dissipation. This means of protection is intended for fault protection only and not as a means of current or power limiting during normal application usage. Proper thermal evaluation should be done to ensure that the junction temperature dose not exceed it’s maximum rating. Operating at the maximum TJ of 150°C can impact reliability . Due to variation in individual device electrical characteristics and thermal resistance , the built in thermal overload protection may be activated at power levels slightly above or below the rated dissipation. Also peak output power should be considered for each individual output. (Note: power dissipation resulting from quiescent (ground) current is negligible) The LX8818 develops a 1.25V reference voltage between the adjust terminal and GND (See Figure 2). By placing a resistor, R2, between these two terminals, a constant current is caused to flow through R1 and down through R2 to set the overall output voltage.. Because IADJ is very small and constant when compared with the current through R2, it represents a small error and can usually be ignored. VIN Thermal Considerations WWW . Microsemi .C OM APPLICATION INFORMATION LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET LM WWW . Microsemi .C OM MECHANICAL DRAWINGS 6-Pin Plastic Exposed Pad JEDEC MO-229 Reference D D1 Dim E/2 E E1 Pin 1 Identifier D/2 TOP VIEW θ A2 θ A .08 Note: SIDE VIEW b 1. Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006”) on any side. Lead dimension shall not include solder coverage. e E3 D2 D2/2 E2/2 E2 (E-L)/2 L MECHANICALS O E3/2 INCHES MIN MAX 0.031 0.041 0.025 0.295 0.012 0.017 0.114 0.127 0.106 --0.070 0.092 0.033 0.041 0.114 0.127 0.106 --0.039 0.061 0.006 0.012 0.007 0.024 --0.005 0° 12° bs ol et e A A2 b D D1 D2 e E E1 E2 E3 L L2 MILLIMETERS MIN MAX 0.80 1.05 0.65 0.75 0.33 0.45 2.90 3.25 2.70 --1.78 2.34 0.85 1.05 2.90 3.25 2.70 --1.01 1.57 0.17 0.30 0.20 0.60 --0.12 0° 12° L2 BOTTOM VIEW Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 8 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET DT 3-Pin Plastic TO-252 Dim P U G N F A B C D E F G H I J K L M N O P Q R S T U V W X MILLIMETERS MIN MAX 6.47 5.97 2.16 0.68 0.38 0.63 2.16 0.84 0.89 2.44 9.55 5.20 7.0° 0.51 0.51 4.19 0.76 0.48 0.89 R0.20 0.51 45° 1.44 0 6.73 6.23 2.42 0.94 0.64 0.89 2.42 1.10 1.15 2.70 9.81 5.46 INCHES MIN MAX 0.255 0.235 0.085 0.027 0.015 0.025 0.085 0.033 0.035 0.096 0.376 0.205 7.0° 0.020 0.020 0.165 0.030 0.019 0.035 R0.008 0.020 45° 0.057 0 0.265 0.245 0.095 0.037 0.025 0.035 0.095 0.043 0.045 0.106 0.386 0.215 bs ol et e J W L A Q O V M H C R D E WWW . Microsemi .C OM MECHANICAL DRAWINGS B X I 1.70 0.10 0.030 0.030 0.175 0.040 0.029 0.045 R0.012 0.030 0.067 0.004 Copyright © 2000 Rev. 1.0a, 2005-03-14 MECHANICALS O K 0.77 0.77 4.45 1.02 0.74 1.15 R0.30 0.77 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 9 LX8818 ® TM 1A Low Dropout Regulator P RODUCTION DATA SHEET O bs ol et e WWW . Microsemi .C OM NOTES NOTES PRODUCTION DATA – Information contained in this document is proprietary to Microsemi and is current as of publication date. This document may not be modified in any way without the express written consent of Microsemi. Product processing does not necessarily include testing of all parameters. Microsemi reserves the right to change the configuration and performance of the product and to discontinue product at any time. Copyright © 2000 Rev. 1.0a, 2005-03-14 Microsemi Integrated Products 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570 Page 10