RT9049 500mA, Low Dropout, Low Noise Ultra-Fast Without Bypass Capacitor CMOS LDO Regulator General Description Features The RT9049 is a high-performance, 500mA LDO regulator, offering extremely high PSRR and ultra-low dropout. The RT9049 is designed for portable RF and wireless applications with demanding performance and space requirements. The RT9049 quiescent current is as low as 115μA, further prolonging the battery life. The RT9049 also works with low-ESR ceramic capacitors, reducing the amount of board space necessary which is critical for power applications in hand-held wireless devices. The RT9049 consumes typical 1.35μA in shutdown mode and has fast turn-on time less than 40μs. The other features include ultra-low dropout voltage, high output accuracy, current limiting protection, and high ripple rejection ratio. The RT9049 is available in the SOT-23-5 package. z Wide Operating Voltage Ranges : 2.2V to 5.5V z Low Dropout : 250mV at 500mA z Ultra-Low-Noise for RF Application z Ultra-Fast Response in Line/Load Transient z Current Limiting Protection z Thermal Shutdown Protection z High Power Supply Rejection Ratio z Only 10μ μF Output Capacitor Required for Stability z 1.35μ μA Shutdown Current z TTL-Logic-Controlled Shutdown Input z RoHS Compliant and Halogen Free Applications CDMA/GSM Cellular Handsets Portable Information Appliances z Laptop, Palmtops, Notebook Computers z HandHeld Instruments z Mini PCI & PCI-Express Cards z PCMCIA & New Cards z z Ordering Information RT9049 Package Type B : SOT-23-5 Lead Plating System G : Green (Halogen Free and Pb Free) Note : Pin Configurations Fixed Output Voltage 12 : 1.2V (TOP VIEW) VOUT Richtek products are : ` NC 5 RoHS compliant and compatible with the current require- 4 2 3 ments of IPC/JEDEC J-STD-020. ` VIN GND EN Suitable for use in SnPb or Pb-free soldering processes. SOT-23-5 Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. Typical Application Circuit 1 VIN VIN CIN 1µF/X7R VOUT 5 VOUT COUT 10µF/X7R RT9049 Chip Enable 3 EN Rpull_down 100k DS9049-01 April 2011 NC 4 GND 2 www.richtek.com 1 RT9049 Function Block Diagram EN Current Limit POR OTP VIN VREF + MOS Driver VOUT GND Functional Pin Description Pin No. Pin Name Pin Function 1 VIN Supply Input. 2 GND 3 EN 4 NC Common Ground. Chip Enable (Active High). When the EN goes to a logic low, the device will be in shutdown mode. No Internal Connection. 5 VOUT Regulator Output. www.richtek.com 2 DS9049-01 April 2011 RT9049 Absolute Maximum Ratings z z z z z z z z (Note 1) Input Voltage, VIN ---------------------------------------------------------------------------------------------------------EN, VEN ---------------------------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOT-23-5 -------------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) SOT-23-5, θJA --------------------------------------------------------------------------------------------------------------SOT-23-5, θJC -------------------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------Junction Temperature ----------------------------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Mode) ---------------------------------------------------------------------------------------------MM (Machine Mode) ------------------------------------------------------------------------------------------------------ Recommended Operating Conditions z z 6V 6V 0.4W 250°C/W 25°C/W 260°C 150°C −65°C to 150°C 2kV 200V (Note 4) Junction Temperature Range -------------------------------------------------------------------------------------------Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C −40°C to 85°C Electrical Characteristics (VIN = 2.7V, VEN = VIN, CIN = 1μF, COUT = 10μF(Ceramic, X7R), TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Input Voltage Range VIN 2.2 -- 5.5 V Output Noise Voltage VON -- 30 -- μV RMS Output Voltage Accuracy ΔV OUT IOUT = 10mA −2 0 +2 % Quiescent Current IQ IOUT = 0mA -- 115 125 μA Shutdown Current ISHDN VEN = 0V -- 1.35 2 μA Current Limit ILIM RLOAD = 0 Ω 1mA < IOUT < 400mA VIN = 2.5V 0.5 0.6 0.85 A -- -- 0.6 % Load Regulation (Note 5) (Note 6) ΔV LOAD Logic-High VIH 1.6 -- -- Logic-Low VIL -- -- 0.6 Enable Pin Current IEN -- 0.1 1 μA Power Supply Rejection Rate PSRR IOUT = 100mA, f = 10kHz -- −50 -- dB Line Regulation ΔV LINE VIN = 2.2V to 5.5V, IOUT = 1mA -- 0.01 0.2 %/V Thermal Shutdown Temperature TSD -- 170 -- °C Thermal Shutdown Hysteresis ΔT SD -- 30 -- °C EN Threshold Voltage DS9049-01 April 2011 V www.richtek.com 3 RT9049 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 thermal conductivity single layer test board of JEDEC 51-3 thermal measurement standard. The case position of θJC is on the package top of 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. Quiescent, or ground current, is the difference between input and output currents. It is defined by IQ = IIN-IOUT under no load condition (IOUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground pin current. Note 6. Regulation is measured at constant junction temperature by using a 2ms current pulse. Devices are tested for loadregulation in the load range from 10mA to 500mA. www.richtek.com 4 DS9049-01 April 2011 RT9049 Typical Operating Characteristics Output Voltage vs. Temperature Quiescent Current vs. Temperature 1.300 140 Quiescent Current (μA) Output Voltage(V) 1.275 1.250 1.225 1.200 1.175 1.150 130 120 110 100 1.125 90 VIN = 2.75V, VOUT = 1.2V, No Load 1.100 VIN = 2.75V, VOUT = 1.2V, No Load 80 -50 -25 0 25 50 75 100 125 -50 Temperature (°C) 0 25 50 75 100 125 Temperature (°C) Line Transient Response Power On-Off from EN VIN (1V/Div) VEN (1V/Div) -25 3.6 2.6 20 VOUT (20mV/Div) 0 VOUT (0.5V/Div) −20 VIN = 2.75V, VOUT = 1.2V, IOUT = 50mA VIN (1V/Div) VIN = 2.6V to 3.6V, VOUT = 1.2V, IOUT = 10mA Time (100μs/Div) Time (100μs/Div) Line Transient Response Load Transient Response VOUT (5mV/Div) 3.6 2.6 20 VOUT (20mV/Div) 0 −20 VIN = 2.6V to 3.6V, VOUT = 1.2V, IOUT = 100mA Time (100μs/Div) DS9049-01 April 2011 IOUT (50mA/Div) VIN = 2.75V, VOUT = 1.2V, IOUT = 10mA to 100mA Time (500μs/Div) www.richtek.com 5 RT9049 Load Transient Response Noise VOUT (5mV/Div) VOUT (100μV/Div) IOUT (100mA/Div) VIN = 2.75V, VOUT = 1.2V, IOUT = 10mA to 300mA VIN = 4.5V (By Battery), VOUT = 1.2V, No Load Time (500μs/Div) Time (10msDiv) Noise PSRR 20 10 PSRR(dB) 0 VOUT (100μV/Div) -10 -20 -30 IOUT = 100mA -40 IOUT = 300mA -50 VIN = 4.5V (By Battery), VOUT = 1.2V, IOUT = 10mA Time (10msDiv) IOUT = 10mA -60 VIN = 2.5V to 2.6V -70 10 100 1000 10000 100000 1000000 Frequency (Hz) www.richtek.com 6 DS9049-01 April 2011 RT9049 Applications Information Like any low-dropout regulator, the external capacitors used with the RT9049 must be carefully selected for regulator stability and performance. Using a capacitor more than 1μF on the RT9049 is suitable. 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. 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 capacitance and ESR in all LDOs application. The RT9049 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 10μF with ESR is > 45mΩ on the RT9049 output ensures stability. The RT9049 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 at less than 0.5 inch from the VOUT pin of the RT9049 and returned to a clean analog ground. Region of Stable COUT ESR (Ω ) Region of Stable COUT ESR vs. Load Current Enable The RT9049 goes into sleep mode when the Enable pin is in a logic low condition. During this condition, the pass transistor, error amplifier, and bandgap are turned off, reducing the supply current to 1.35μA typical. The Enable pin may be directly tied to VIN to keep the part on. The Enable input is CMOS logic and cannot be left floating. PSRR The power supply rejection ratio (PSRR) is defined as the gain from the input to output divided by the gain from the supply to the output. The PSRR is found to be ⎛ ΔGain Error ⎞ ⎟⎟ PSRR = 20 × log⎜⎜ ⎝ ΔSupply ⎠ Note that when heavy load measuring, Δsupply will cause Δtemperature. And Δtemperature will cause Δoutput voltage. So the heavy load PSRR measuring is includes temperature effect. Current Limit The RT9049 contains an independent current limiter, which monitors and controls the pass transistor's gate voltage, limiting the output current to 0.6A (typ.). The output can be shorted to ground indefinitely without damaging the part. 100 Thermal Considerations Unstable Range For continuous operation, do not exceed absolute maximum operation junction temperature. 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 : 10 1 RT9049 -12GB VIN = 2.75V COUT = 10μF/X7R 0.1 Stable Range Unstable Range PD(MAX) = (TJ(MAX) − TA) / θJA 0.01 0 0.1 0.2 0.3 0.4 0.5 Load Current (mA) Figure 1.Region of Stable COUT ESR vs. Load Current DS9049-01 April 2011 Where T J(MAX) is the maximum operation junction temperature, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. For recommended operating conditions specification of RT9049, the maximum junction temperature is 125°C. The junction to ambient thermal resistance θJA is layout dependent. For SOT-23-5 package, the thermal resistance www.richtek.com 7 RT9049 θJA is 250°C/W on the standard JEDEC 51-3 single layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by following formula : P D(MAX) = (125°C − 25°C) / (250°C/W) = 0.4W for SOT-23-5 package Maximum Power Dissipation (W)1 The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance θJA. For RT9049 package, the Figure 2 of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power dissipation allowed. 0.50 Single Layer PCB 0.45 0.40 0.35 SOT-23-5 0.30 0.25 0.20 0.15 0.10 0.05 0.00 0 25 50 75 100 125 Ambient Temperature (°C) Figure 2. Derating Curves for RT9049 Package www.richtek.com 8 DS9049-01 April 2011 RT9049 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. DS9049-01 April 2011 www.richtek.com 9