RT9037 300mA, Low Noise, Ultra-Fast CMOS LDO Regulator General Description Features The RT9037 is designed for portable RF and wireless applications with demanding performance and space requirements. The RT9037 performance is optimized for battery-powered systems to deliver ultra low noise and low quiescent current. Regulator ground current increases only slightly in dropout, further prolonging the battery life. The RT9037 also works with low-ESR ceramic capacitors, reducing the amount of board space necessary for power applications, critical in hand-held wireless devices. The RT9037 consumes less than 0.01uA in shutdown mode and has fast turn-on time less than 50us. The other features include ultra low dropout voltage, high output accuracy, current limiting protection, and high ripple rejection ratio. Available in the SOT-23-5 package, the RT9037 also offers a wide output voltage range from 3.3V to 5V with 0.1V per step. z Low-Noise for RF Application z Fast Response in Line/Load Transient Quick Start-Up (Typically 50us) < 0.01uA Standby Current When Shutdown Low Dropout : 220mV @ 300mA Wide Operating Voltage Ranges : 2.5V to 5.5V TTL-Logic-Controlled Shutdown Input Low Temperature Coefficient Current Limiting Protection Thermal Shutdown Protection Only 1uF Output Capacitor Required for Stability High Power Supply Rejection Ratio Custom Voltage Available RoHS Compliant and Halogen Free Ordering Information RT9037 Lead Plating System G : Green (Halogen Free and Pb Free) Output Voltage 33 : 3.3V 34 : 3.4V : 49 : 4.9V 50 : 5.0V 1H : 1.85V 2H : 2.85V 4G : 4.75V Richtek products are : ` RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. ` z z z z z z z z z z z Applications z z z Package Type B : SOT- 23-5 BR : SOT- 23-5 (R-Type) Note : z Suitable for use in SnPb or Pb-free soldering processes. Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. DS9037-01 April 2011 z z z CDMA/GSM Cellular Handsets Battery-Powered Equipment Laptop, Palmtops, Notebook Computers Hand-Held Instruments PCMCIA Cards Portable Information Appliances Pin Configurations (TOP VIEW) VIN VOUT 5 4 2 3 EN NC GND SOT-23-5 VOUT NC 5 4 2 3 VIN GND EN SOT-23-5 (R-Type) www.richtek.com 1 RT9037 Typical Application Circuit RT9037 VIN CIN 1uF Chip Enable On VIN VOUT COUT 1uF EN VOUT GND Off Functional Pin Description Pin Name Pin Function EN Chip Enable (Active High). Note that this pin is high impedance. There should be a pull low 100kΩ resistor connected to GND when the control signal is floating. NC No Internal Connection. GND Ground. VOUT Output Voltage. VIN Input Voltage. Function Block Diagram EN Shutdown and Logic Control VIN VREF - MOS Driver + Error Amplifier Current-Limit and Thermal Protection VOUT GND www.richtek.com 2 DS9037-01 April 2011 RT9037 Absolute Maximum Ratings (Note 1) Supply Input Voltage -----------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOT-23-5 -------------------------------------------------------------------------------------------------------------------z Package Thermal Resistance (Note 2) SOT-23-5, θJA --------------------------------------------------------------------------------------------------------------z Junction Temperature ----------------------------------------------------------------------------------------------------z Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------z Storage Temperature Range -------------------------------------------------------------------------------------------z ESD Susceptibility (Note 3) HBM (Human Body Mode) ---------------------------------------------------------------------------------------------MM (Machine Mode) -----------------------------------------------------------------------------------------------------z 6V z Recommended Operating Conditions z z z z 400mW 250°C/W 150°C 260°C −65°C to 150°C 2kV 200V (Note 4) Supply Input Voltage -----------------------------------------------------------------------------------------------------EN Input Voltage ----------------------------------------------------------------------------------------------------------Junction Temperature Range -------------------------------------------------------------------------------------------Ambient Temperature Range -------------------------------------------------------------------------------------------- 2.5V to 5.5V 0V to 5.5V −40°C to 125°C −40°C to 85°C Electrical Characteristics (VIN = VOUT + 1V, CIN = COUT = 1uF, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Output Voltage Accuracy ΔV OUT IOUT = 1mA −2 -- +2 % Current Limit ILIM RLOAD = 1Ω 360 400 -- mA Quiescent Current IQ VEN ≧ 1.2V, IOUT = 0mA -- 90 130 uA IOUT = 200mA -- 170 200 -- 220 330 -- -- 0.3 % -- -- 0.6 % Dropout Voltage (Note 5) VDROP mV Line Regulation ΔV LINE Load Regulation ΔV LOAD IOUT = 300mA VIN = (VOUT + 1V) to 5.5V, IOUT = 1mA 1mA < IOUT < 300mA Shutdown Current ISHDN VEN = GND, Shutdown -- 0.01 1 uA EN Input Bias Current IIBEN VEN = GND or V IN -- 0 100 nA VIL VIN = 3V to 5.5V, Shutdown -- -- 0.4 1.2 -- -- -- −60 -- -- −30 -- EN Threshold Logic-Low Voltage Logic-High Voltage VIH VIN = 3V to 5.5V, Enable V Power Supply f = 100Hz Rejection Rate f = 10kHz PSRR Thermal Shutdown Temperature TSD -- 165 -- °C Thermal Shutdown Temperature Hysteresis ΔT SD -- 30 -- °C DS9037-01 April 2011 COUT = 1uF, IOUT = 100mA dB www.richtek.com 3 RT9037 Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for stress ratings. Functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may remain possibility to affect device reliability. Note 2. θJA is measured in the natural convection at TA = 25°C on a low effective single layers thermal conductivity test board of JEDEC 51-3 thermal measurement standard. The case point of θJC is on the exposed pad for the package. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. Note 5. The dropout voltage is defined as VIN -VOUT, which is measured when VOUT is VOUT(NORMAL) − 100mV. www.richtek.com 4 DS9037-01 April 2011 RT9037 Typical Operating Characteristics Quiesent Current vs. Temperature Output Voltage vs. Temperature 100 VIN = 5V CIN = COUT = 1uF VIN = 3.3V CIN = COUT = 1uF 95 Quiescent Current (uA) Output Voltage (V) 2 1.9 1.8 No Load 1.7 90 85 80 75 70 65 60 1.6 -50 -25 0 25 50 75 100 -50 125 -25 0 RT9037-15 VIN = 3.3V CIN = COUT = 1uF 0.75 0.50 125 CIN = COUT = 1uF 500 450 400 350 300 0.25 -50 -25 0 25 50 75 100 2 125 2.5 3 Temperature (°C) 20 VOUT = 3.3V CIN = COUT = 1uF 3.5 4 4.5 5 5.5 6 6.5 Input Voltage (V) Dropout Voltage vs. Load Current TJ = 125°C 250 PSRR VOUT = 2.5V CIN = COUT = 1uF, X7R 0 200 TJ = 25°C PSRR (dB) Dropout Voltage (mV) 100 550 Current Limit (mA) EN Threshold Voltage (V) 600 1.00 300 75 Current Limit vs. Input Voltage EN Threshold Voltage vs. Temperature 1.25 50 Temperature (°C) Temperature (°C) 1.50 25 150 TJ = -40°C 100 -20 -40 ILOAD = 100mA -60 50 ILOAD = 10mA 0 -80 0 0.05 0.1 0.15 0.2 Load Current (A) DS9037-01 April 2011 0.25 0.3 10 0.01 100 0.1 1K 1 10K 10 100K 100 1M 1000 Frequency (kHz) (Hz) www.richtek.com 5 RT9037 Line Transient Response ILOAD = 50mA 4 3 Input Voltage Deviation (V) CIN = COUT = 1uF 5 Output Voltage Deviation (mV) Output Voltage Deviation (mV) Input Voltage Deviation (V) Line Transient Response 20 0 -20 CIN = COUT = 1uF 4 3 50 0 -50 Time (100μs/Div) Time (100μs/Div) 50 Output Voltage Deviation (mV) 0 50 0 -50 10 400 VIN = 3.3V CIN = COUT = 1uF VOUT = 1.5V ILOAD = 1mA to 250mA 200 0 50 0 -50 Time (100μs/Div) Time (100μs/Div) Start Up Noise RT9037-18, VIN = 5V CIN = COUT = 1uF VOUT = 1.8V ILOAD = 1mA 5 400 0 200 2 1 VOUT = 1.8V ILOAD = 150mA VIN = 4.5V CIN = COUT = 1uF Noise (μV) EN Pin Voltage (V) Output Voltage (V) VOUT = 1.5V ILOAD= 1mA to 50mA Load Transient Response Load Current (mA) 100 Output Voltage Deviation (mV) Load Current (mA) Load Transient Response VIN = 3.3V CIN = COUT = 1uF ILOAD = 250mA 5 0 -200 -400 0 f = 10Hz to 100kHz Time (10μs/Div) www.richtek.com 6 Time (5ms/Div) DS9037-01 April 2011 RT9037 Applications Information Like any low-dropout regulator, the external capacitors used for the RT9037 must be carefully selected for regulator stability and performance. Using a capacitor whose value is > 1uF on the RT9037 input and the amount of capacitance can be increased without limit. The input capacitor must be located at 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. Enable Function The output capacitor must meet both requirements for minimum amount of capacitance and ESR in all LDOs application. The RT9037 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 1uF with ESR is more than 20mΩ on the RT9037 output ensures stability. The RT9037 still works well with output capacitor of other types due to the wide stable ESR range. Figure 1. shows the curves of allowable ESR range as a function of load current for various output capacitor values. Output capacitor of larger capacitance can reduce noise and improve load transient response, stability, and PSRR. The output capacitor should be located with in 0.5 inch from the VOUT pin of the RT9037 Thermal Considerations and returned to a clean analog ground. Region of Stable COUT ESR vs. Load Current 100.00 100 C OUT ESR (Ω) To assure the RT9037 LDO regulator will switch on, the EN turn on control level must be greater than 1.2V. The RT9037 LDO regulator will go into shutdown mode when the voltage on the EN pin falls below 0.4V. If the enable function is not needed in a specific application, it may be tied to GND/VIN to keep the LDO regulator in a continuously on state. Thermal protection limits power dissipation in the RT9037. When the operating junction temperature exceeds 165°C, the OTP circuit starts the thermal shutdown function and turns the pass element off. The pass element turns on again after the junction temperature cools by 30°C. For continuous operation, do not exceed absolute maximum operatiog junction temperature 125°C. The power dissipation definition in device is shown as following formula : PD = (VIN − VOUT) x IOUT + VIN x IQ The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference between junction to ambient. The maximum power dissipation can be calculated by following formula : PD(MAX) = ( TJ(MAX) - TA ) / θJA Instable 10 10.00 COUT = 1uF 1.001 Stable 0.10 0.01 0.00 The RT9037 features an LDO regulator enable/disable function. RT9037-15xU5 COUT = 1μF, X7R 0 50 Simulation Verify 100 150 200 Load Current (mA) 300 For recommended operating conditions specification of the RT9037, the maximum junction temperature of the die is 125°C. The junction to ambient thermal resistance (θJA is layout dependent) for SOT-23-5 package is 250°C/ W on standard JEDEC 51-3 thermal test board. The maximum power dissipation at TA = 25°C can be calculated by following formula : PD(MAX) = (125°C − 25°C)/250 = 400mW (SOT-23-5) Figure 1 DS9037-01 April 2011 250 Where T J(MAX) is the maximum operating junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. The maximum power dissipation depends on operating Instable www.richtek.com 7 RT9037 Maximum Power Dissipation (mW)1 ambient temperature for fixed T J(MAX) and thermal resistance θJA. For the RT9037 packages, the Figure 2. of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. 700 600 500 400 300 200 100 0 0 15 30 45 60 75 90 105 120 135 Ambient Temperature (°C) Figure 2. Derating Curve for Packages www.richtek.com 8 DS9037-01 April 2011 RT9037 Outline Dimension H D L B C b A A1 e Dimensions In Millimeters Dimensions In Inches Symbol 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 SOT-23-5 Surface Mount Package Richtek Technology Corporation Richtek Technology Corporation Headquarter Taipei Office (Marketing) 5F, No. 20, Taiyuen Street, Chupei City 5F, No. 95, Minchiuan Road, Hsintien City Hsinchu, Taiwan, R.O.C. Taipei County, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Tel: (8862)86672399 Fax: (8862)86672377 Email: [email protected] Information that is provided by Richtek Technology Corporation is believed to be accurate and reliable. Richtek reserves the right to make any change in circuit design, specification or other related things if necessary without notice at any time. No third party intellectual property infringement of the applications should be guaranteed by users when integrating Richtek products into any application. No legal responsibility for any said applications is assumed by Richtek. DS9037-01 April 2011 www.richtek.com 9