A6318 AITSEMI | Alldatasheet
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AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 1 - DESCRIPTION FEATURES The A6318 is a high performance linear voltage regulator with adjustable output with a 1.23 reference voltage. It operates from an input of 2V to 6V and provides output current up to 300mA with two external resistors to set the outpu t voltage. The A6318 designed for portable RF and wireless applications with demanding performance and space requirements. Optimized for battery -powered systems to deliver ultra-low noise and low quiescent current. A noise FB pin is available for further r eduction of output noise. Regulator ground current increases only slightly in dropout, further prolonging the battery life. The A6318 works with low -ESR ceramic capacitors, reducing the PCB space. The A6318 consumes less than 0.01μA in shutdown mode and has fast turn-on time less than 50μs. The A6318 has superior regulation over variations in line and load. Also it provides fast respond to step changes in load. Other features include over-current and over-temperature protection and high ripple rejection ratio. The A6318 is available in SOT-25 package Low Dropout:210mV@300mA TTL-logic-Controlled Shutdown Input <0.01μA Standby Current When Shutdown Ultra-low noise for RF Application Ultra-Fast Response in Line/Load Transient Quick Start-Up (Typically 50μS) Wide Operating Voltage Ranges: 2V to 6V Low Temperature Coefficient Current Limiting Protection Thermal Shutdown Protection Only 1μF Output Capacitor Required for Stability High Power Supply Rejection Ratio Fast output discharge Available in SOT-25 package APPLICATION Battery-Powered Equipment Cellular and Smart Phones Graphic Card, Laptop, Palmtops, Notebook Computers Hand-Held Instruments Peripheral Cards PCMCIA Card ORDERING INFORMATION TYPICAL APPLICATION Package Type Part Number SOT-25 SPQ: 3,000pcs/Reel A6318E5R-ADJ A6318E5VR-ADJ Note ADJ=Adjustable V: Halogen free Package R: Tape & Reel AiT provides all RoHS products
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 2 - PIN DESCTRIPTION Top View Pin # Symbol Function
1 VIN Power Input Voltage
2 GND Ground
3 EN Active high with internal 8 mΩ pull down
4 FB Feedback
5 VOUT Output Voltage
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 3 - ABSOLUTE MAXIMUM RATING VCC, Input Supply Voltage -0.3V ~ +6V EN Input Voltage -0.3V ~ +VIN Output Voltage -0.3V ~ VIN+0.3V FB Voltage -0.3V ~ VIN+0.3V Output Current 300mA PD, Power Dissipation 350mW Maximum Junction Temperature 125°C Operating Temperature RangeNOTE1 -40°C ~ 85°C Storage Temperature Range -65°C ~ 125°C Lead Temperature (Soldering, 10s) 300°C Stresses beyond may cause per manent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated in the Electrical Characteristics are not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. NOTE1: The A6318 is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the -40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. THERMAL RESISTANCENOTE2 Package θJA θJC SOT-25 250°C/W 130°C/W NOTE2: Thermal Resistance is specified with approximately 1 square of 1 oz copper
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 4 - ELECTRICAL CHARACTERISTICSNOTE3 VIN=3.6V, EN=VIN, CIN=COUT=1μF, CFB=22nF, TA=25℃, unless otherwise noted Parameter Symbol Conditions Min Typ. Max Unit Input Voltage VIN 2 - 6 V Output Voltage Accuracy ΔVOUT VIN=3.6V, IOUT=1mA -1 - +1 % -2 - +2 VIN=3.4V, IOUT=300mA -2.5 - +2.5 Current Limit ILIM RLOAD=1Ω 400 430 - mA Quiescent Current IQ VEN>1.2V, IOUT=0mA - 90 130 μA Dropout Voltage VDROP IOUT=200mA, VOUT=2.8V - 130 180 mV IOUT=300mA, VOUT=2.8V - 210 300 Line RegulationNOTE4 ΔVLINE VIN=3.6V to 5.5V, IOUT=1mA - 0.05 0.17 %/V Load RegulationNOTE5 ΔVLOAD 1mA<IOUT<300mA - - 2 %/A Output Voltage Temperature CoefficientNOTE6 TCVOUT IOUT=1mA - ±60 - ppm/℃ Standby Current ISTBY VEN=GND, Shutdown - 0.01 1 μA EN Input Bias Current IIBSD VEN=GND or VIN - 0 100 nA EN Input Threshold Logic Low VIL VIN=3V to 5.5V,Shutdown - - 0.4 V Logic High VIH VIN=3V to 5.5V,Start up 1.2 - - Output Noise Voltage eNO 10Hz to100kHz, IOUT=200mA, COUT=1μF - 100 - μVRMS Power Supply Rejection Ratio f=217Hz PSRR COUT=1uF, IOUT=100mA - -80 - dB f=1kHz - -78 - f=10kHz - -65 - Thermal Shutdown Temperature TSD Shutdown, Temp increasing - 165 - ℃ Thermal Shutdown Hysteresis TSDHY - 30 - ℃ NOTE3: 100% production test at +25°C. Specifications over the temperature range are guaranteed by design and characterization. NOTE4: Line regulation is calculated by ΔVLINE= [(VOUT1-VOUT2)/(ΔVINxVOUT(normal))]x100 NOTE5: Load regulation is calculated by ΔVLOAD= [(VOUT1-VOUT2)/(ΔIOUTxVOUT(normal))]x100 Where V OUT1 is the output voltage when I OUT=1mA, and V OUT2 is the output voltage when I OUT=300mA. ΔIOUT=0.299A, VOUT (normal) =2.8V. NOTE6: The temperature coefficient is calculated by TCVOUT=ΔVOUT /(ΔTxVOUT)
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 5 - TYPICAL PERFORMANCE CHARACTERISTICS 1. Output Voltage vs. Temperature 2. Quiescent Current vs. Temperature 3. Dropout Voltage vs. Load Current 4. PSRR 5. EN Pin Shutdown Threshold vs. Temperature 6. EN Pin Shutdown Response
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 6 - 7. Load Transient Response 8. Load Transient Response 9. Line Transient Response 10. Line Transient Response 11. Start Up
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 7 - BLOCK DIAGRAM
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 8 - APPLICATIONS INFORMATION Like any low -dropout regulator, the external capacitors used with the A6318 must be carefully selected for regulator stability and performance. Using a capacitor whose value is > 1μF on the A6318 input and the amount of capacitance can be increased without limit. The input capacitor must be located a distance of not more than 0.5 inch from the input pin of the IC and returned to a clean analog ground. Any good quality ceramic or tantalum can be used for this capacitor. The capacitor with larger value and lower ESR (equivalent series resistance) provides better PSRR and line-transient response. The output capacitor must meet both requirements for minimum amount of capacitance and ESR in all LDOs application. The A6318 is designed specifically to work with low ESR ceramic output capacitor in space -saving and performance consideration. Using a ceramic capacitor whose value is at least 1μF with ESR is > 25mΩ on the A6318 output ensures stability. The A6318 still works well with output capacitor of other types due to the wide stable ESR range. Output capacitor of larger capacitance can reduce noise and improve load transient response, stability, and PSRR. The output capacitor should be located not more than 0.5 inch from the VOUT pin of the A6318 and returned to a clean analog ground. FB Capacitor and Low Noise Connecting a 22nF between the FB pin and GND pin significantly reduces noise on the regulator output, it is critical that the capacitor connection between the FB pin and GND pin be direct and PCB traces should be as short as possible. There is a relationship between the FB capacitor value and the LDO regulator turn on time. DC leakage on this pin can affect the LDO regulator output noise and voltage regulation performance. Enable Function The A6318 features an LDO regulator enable/ disable function. To assure the LDO regulator will switch on; the EN turn on control level must be greater than 1.2 volts. The LDO regulator will go into the shutdown mode when the voltage on the EN pin falls below 0.4 volts. For to protect the system, the A6318 have a quick discharge function. If the enable function is not needed i n a specific application, it may be tied to VIN to keep the LDO regulator in a continuously on state.
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 9 - Programming the A6318 Adjustable LDO regulator The output voltage of the A6318 adjustable regulator is programmed using an external resistor divider as show in Figure as below. The output voltage is calculated using equation as below: VOUT = VREF X R2 R1 1 Where: VREF=1.23V typ . (the internal reference voltage) .Resistors R1 and R2 should be chosen for approximately 50uA divider current . Lower value resistors can be used for improved noise performance, but the solution consumes more power. Higher resistor values should be avoided as leakage current into/out of FB across R1/R2 creates an offset voltage that artificially increases/decreases the feedback voltage and thus erroneously decrease/increases VOUT. The recommended design pr ocedure is to choose R2= 30.1kΩ to set the divider current at 50uA, C1=22pF for stability, and then calculate using Equation as below: R1 = R2 X 1 - V V REF OUT In order to improve the stability of the adjustable version, it is suggested that a small compensation capacitor be placed between OUT and FB. The suggested value of this capacitor for several resistor ratios is shown in the table below. OUTPUT VOLTAGE PROGRAMMING GUIDE OUTPUT VOLTAGTE R1 R2 C1 1.8V 13.9 kΩ 30.1 kΩ 22pF 2.5V 31.6 kΩ 30.1 kΩ 22pF 3.3V 51 kΩ 30.1 kΩ 22pF 3.6V 59 kΩ 30.1 kΩ 22pF A6318 Adjustable LDO regulator Programming
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 10 - Thermal Considerations Thermal protection limits power dissipation in A6318. When the operation junction temperature exceeds 165°C, the OTP circuit starts the thermal shutdown function turn the pass element off. The pass element turns on again after the junction temperature cools by 30°C. For continue operation, do not exceed absolute maximum operation junction temperature 125°C. The power dissipation definition in device is: PD = (VIN−VOUT) ×IOUT + VIN×IQ The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference betw een junction to ambient. The maximum power dissipation can be calculated by following formula： PD(MAX) = ( TJ(MAX) − TA ) /θJA Where TJ(MAX) is the maximum operation junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. For recommended operating conditions specification of A6318, where T J(MAX) is the maximum junction temperature of the die (125°C) and T A is the maximum ambient temperature. The junction to ambient thermal resistance ( θJA is layout dependent) for SOT -25 package is 250°C/W, on standard JEDEC 51-3 thermal tes t board. The maximum power dissipation at T A= 25°C can be calculated by following formula: PD(MAX) = (125°C−25°C)/250 = 400mW The maximum power dissipation depends on operating ambient temperat ure for fixed TJ(MAX) and thermal resistance θJA. It is also useful to calculate the junction of temperature of the A6318 under a set of specific conditions. In this example let the Input voltage V IN=3.3V, the output current Io=300mA and the case temperature TA=40°C measured by a thermal couple during operation. The power dissipation for the VOUT=2.8V version of the A6318 can be calculated as: PD = (3.3V−2.8V) ×300mA+3.6V×100uA =150mW And the junction temperature, TJ, can be calculated as follows: TJ=TA+PD×θJA=40°C+0.15W×250°C/W=40°C+37.5°C=77.5°C<TJ(MAX) =125°C
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 11 - For this operating condition, TJ is lower than the absolute maximum operating junction temperature, 125°C, so it is safe to use the A6318 in this configuration. Layout considerations To improve ac performance such as PSRR, output noise, and transient response, it is recommended that the PCB be designed with separate ground planes for VIN and VOUT, with each ground plane connected only at the GND pin of the device. In addition, the ground connection for the FB capacitor should connect directly to the GND pin of the device. TOP Layer Layout BOTTOM Layer Layout
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 12 -
PACKAGE INFORMATION
Dimension in SOT-25 (Unit: mm) Symbol Millimeters Inches Min Max Min Max A 0.889 1.295 0.035 0.051 A1 0.000 0.152 0.000 0.006 B 1.397 1.803 0.055 0.071 b 0.356 0.559 0.014 0.022 C 2.591 2.997 0.102 0.118 D 2.692 3.099 0.106 0.122 e 0.838 1.041 0.033 0.041 H 0.080 0.254 0.003 0.010 L 0.300 0.610 0.012 0.024
AiT Semiconductor Inc. www.ait-ic.com A6318 REGULATOR CMOS LOW DROPOUT REGULATOR (LDO) 300mA UL TRA-LOW NOISE, UL TRA-FAST REV2.2 - JAN 2010 RELEASED, JAN 2019 UPDATED - - 13 - IMPORTANT NOTICE AiT Semiconductor Inc. (AiT) reserves the right to make changes to any its product, specifications, to discontinue any integrated circuit product or service without notice, and advises its customers to obtain the latest version of rele vant information to verify, before placing orders, that the information being relied on is current. AiT Semiconductor Inc.’s integrated circuit products are not designed, intended, authorized, or warranted to be suitable for use in life support applicati ons, devices or systems or other critical applications. Use of AiT products in such applications is understood to be fully at the risk of the customer. As used herein may involve potential risks of de ath, personal injury, or server property, or environm ental damage. In order to minimize risks associated with the customer's applications, the customer should provide adequate design and operating safeguards. AiT Semiconductor Inc . assumes to no liability to customer product design or application support . AiT warrants the performance of its products of the specifications applicable at the time of sale.