RT9198T 300mA, Thermal Folded Back CMOS LDO Regulator General Description Features The RT9198T is designed for portable RF and wireless applications with demanding performance and space requirements. The RT9198T 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 RT9198T also works with low-ESR ceramic capacitors, reducing the amount of board space necessary for power applications, critical in hand-held wireless devices. The RT9198T consumes less than 0.01uA in shutdown mode and has fast turn-on time less than 50μs. RT9198T is short circuit thermal folded back protected. RT9198T lowers its OTP trip point from 165°C to 110°C when output short z Short Circuit Thermal Folded Back Protection z circuit occurs (VOUT < 0.4V) providing maximum safety to end users. The other features include ultra low dropout voltage, high output accuracy, current limiting protection, and high ripple rejection ratio. Available in the SOT-23-3, SOT-23-5 and SC-70-5 packages, the RT9198T also offers a range of 1.5V to 3.5V with 0.1V per step. z Low-Noise for RF Application 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 100% Lead (Pb)-Free z z z z z z z z z z z z Applications z z z Ordering Information z RT9198T- z Package Type U5 : SC-70-5 U5R : SC-70-5 (R-Type) V : SOT-23-3 B : SOT- 23-5 BR : SOT- 23-5 (R-Type) Lead Plating System P : Pb Free G : Green (Halogen Free and Pb Free) Note : Output Voltage 15 : 1.5V 16 : 1.6V : 34 : 3.4V 35 : 3.5V 1H : 1.85V 2H : 2.85V Richtek products are : ` RoHS compliant and compatible with the current require- ` Suitable for use in SnPb or Pb-free soldering processes. z CDMA/GSM Cellular Handsets Battery-Powered Equipment Laptop, Palmtops, Notebook Computers Hand-Held Instruments PCMCIA Cards Portable Information Appliances Marking Information For marking information, contact our sales representative directly or through a Richtek distributor located in your area. Pin Configurations (TOP VIEW) VIN 3 2 GND VOUT SOT-23-3 ments of IPC/JEDEC J-STD-020. DS9198T-04 April 2011 www.richtek.com 1 RT9198T VIN VOUT VOUT NC 5 4 5 4 2 3 2 3 EN NC GND VIN GND EN SOT-23-5/SC-70-5 SOT-23-5/SC-70-5 (R-Type) Typical Application Circuit RT9198T VIN VIN CIN 1uF VOUT COUT 1uF Chip Enable EN VOUT GND Functional Pin Description Pin Name EN Pin Function 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 Connection GND Ground VOUT Output Voltage VIN Input Voltage Function Block Diagram EN Shutdown and Logic Control VIN VREF + - Error Amplifier MOS Driver VOUT Current-Limit and Thermal Protection GND www.richtek.com 2 DS9198T-04 April 2011 RT9198T Absolute Maximum Ratings z z z z z z z (Note 1) Supply Input Voltage ---------------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOT-23-3 ------------------------------------------------------------------------------------------------------------------SOT-23-5 ------------------------------------------------------------------------------------------------------------------SC-70-5 -------------------------------------------------------------------------------------------------------------------Package Thermal Resistance (Note 2) SOT-23-3, θJA ------------------------------------------------------------------------------------------------------------SOT-23-5, θJA ------------------------------------------------------------------------------------------------------------SC-70-5, θJA --------------------------------------------------------------------------------------------------------------Junction Temperature --------------------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------------------Storage Temperature Range ------------------------------------------------------------------------------------------ESD Susceptibility (Note 3) HBM (Human Body Mode) --------------------------------------------------------------------------------------------MM (Machine Mode) ---------------------------------------------------------------------------------------------------- Recommended Operating Conditions z z z 6V 0.4W 0.4W 0.3W 250°C/W 250°C/W 333°C/W 150°C 260°C −65°C to 150°C 2kV 200V (Note 4) Supply Input Voltage ---------------------------------------------------------------------------------------------------- 2.5V to 5.5V Operation Ambient Temperature Range ----------------------------------------------------------------------------- −40°C to 85°C Operation Junction Temperature Range ----------------------------------------------------------------------------- −40°C to 125°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 ΔVOUT 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 IOUT = 300mA -- 220 330 VIN = (VOUT + 1V) to 5.5V, IOUT = 1mA -- -- 0.3 % Dropout Voltage (Note 5) V DROP mV Line Regulation ΔVLINE Load Regulation ΔVLOAD 1mA < IOUT < 300mA -- -- 0.6 % Standby Current ISTBY VEN = GND, Shutdown -- 0.01 1 uA EN Input Bias Current IIBSD VEN = GND or VIN -- 0 100 nA V IL VIN = 3V to 5.5V, Shutdown -- -- 0.4 1.2 -- -- -- −60 -- -- −30 -- EN Threshold Power Supply Rejection Rate Logic-Low Voltage Logic-High Voltage V IH f = 100Hz f = 10kHz PSRR VIN = 3V to 5.5V, Start-Up COUT = 1uF, IOUT = 100mA V dB Thermal Shutdown Temperature T SD -- 165 -- °C Thermal Shutdown Temperature Hysteresis ΔT SD -- 30 -- °C -- 110 -- °C Thermal Folded Back DS9198T-04 April 2011 www.richtek.com 3 RT9198T 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 test board of JEDEC 51-3 thermal measurement standard. 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 DS9198T-04 April 2011 RT9198T Typical Operating Characteristics Quiesent Current vs. Temperature Output Voltage vs. Temperature 100 VIN = 5V CIN = COUT = 1uF RT9198T-15PB 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 EN Pin Shutdown Threshold vs. Temperature Current Limit (mA) EN Pin Threshold Voltage (V) 0.75 0.5 125 RT9198T-15PB CIN = COUT = 1uF 500 450 400 350 0.25 300 -50 -25 0 25 50 75 100 125 2 2.5 3 Temperature (°C) 20 RT9198T-33PB 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 1 300 75 Current Limit vs. Input Voltage 600 RT9198T-15PU5 VIN = 3.3V CIN = COUT = 1uF 1.25 50 Temperature (°C) Temperature (°C) 1.5 25 150 TJ = -40°C 100 -20 -40 ILOAD = 100mA -60 50 ILOAD = 10mA -80 0 0 0.05 0.1 0.15 0.2 Load Current (A) DS9198T-04 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 RT9198T Line Transient Response Input Voltage Deviation (V) CIN = COUT = 1uF ILOAD = 50mA 5 4 Output Voltage Deviation (mV) Output Voltage Deviation (mV) 3 Input Voltage Deviation (V) Line Transient Response 20 0 -20 CIN = COUT = 1uF 4 3 50 0 -50 Time (100μs/Div) Time (100μs/Div) Output Voltage Deviation (mV) 0 50 0 -50 10 Load Current (mA) 50 VOUT = 1.5V ILOAD = 1mA to 250mA 200 0 50 0 -50 Time (100μs/Div) Start Up EN Pin Shutdown Response VIN = 5V CIN = COUT = 1uF 5 0 2 1 0 Time (10μs/Div) www.richtek.com 6 400 VIN = 3.3V CIN = COUT = 1uF Time (100μs/Div) VOUT = 1.8V ILOAD = 1mA Output Voltage (V) EN Pin Voltage (V) Output Voltage (V) VOUT = 1.5V ILOAD = 1mA to 50mA Load Transient Response EN Pin Voltage (V) 100 Output Voltage Deviation (mV) Load Current (mA) Load Transient Response VIN = 3.3V CIN = COUT = 1uF ILOAD = 250mA 5 10 VOUT = 1.8V ILOAD = 1mA VIN = 5V CIN = COUT = 1uF 5 0 2 1 0 Time (1ms/Div) DS9198T-04 April 2011 RT9198T Noise Noise VOUT = 1.8V ILOAD = 150mA 400 400 200 200 0 -200 -400 0 -200 -400 f = 10Hz to 100kHz Time (5ms/Div) DS9198T-04 April 2011 VOUT = 1.8V No Load VIN = 4.5V CIN = COUT = 1uF Noise (μV) Noise (μV) VIN = 4.5V CIN = COUT = 1uF f = 10Hz to 100kHz Time (5ms/Div) www.richtek.com 7 RT9198T Applications Information Like any low-dropout regulator, the external capacitors used with the RT9198T must be carefully selected for regulator stability and performance. Using a capacitor whose value is > 1μF on the RT9198T 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. Enable Function The output capacitor must meet both requirements for minimum amount of capacitance and ESR in all LDOs application. The RT9198T is designed specifically to work with low ESR ceramic output capacitor in space-saving Thermal Considerations and performance consideration. Using a ceramic capacitor whose value is at least 1μF with ESR is > 20mΩ on the RT9198T output ensures stability. The RT9198T 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 not more than 0.5 inch from the VOUT pin of the RT9198T and returned to a clean analog ground. The RT9198T 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 protecting the system, the RT9198T have a quickdischarge function. If the enable function is not needed in a specific application, it may be tied to VIN to keep the LDO regulator in a continuously on state. Thermal protection limits power dissipation in RT9198T. When the operation junction temperature exceeds 165°C, the OTP circuit starts the thermal shutdown function and turns the pass element off. The pass element turn on again after the junction temperature cools by 30°C. RT9198T lowers its OTP trip level from 165°C to 110°C when output short circuit occurs (VOUT < 0.4V) as shown in Figure 2. This limits IC case temperature under 100°C and provides maximum safety to end users when output short circuit occurs. VOUT Short to GND 0.4V Region of Stable COUT ESR vs. Load Current VOUT 100.00 100 C OUT ESR (Ω) IOUT Instable 10 10.00 COUT = 1uF 1.001 165 °C 110 C ° OTP Trip Point 110 °C Stable 0.10 0.01 0.00 TSD IC Temperature 0 50 80 °C Simulation Verify RT9198T-15PU5 CIN = 1μF, X7R 100 150 200 Load Current (mA) 250 300 Figure 2. Short Circuit Thermal Folded Back Protection when Output Short Circuit Occurs Figure 1 www.richtek.com 8 DS9198T-04 April 2011 RT9198T 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 Where T J(MAX) is the maximum operation junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. 450 Maximum Power Dissipation (mW) For continuous operation, do not exceed absolute maximum operation junction temperature 125°C. The power dissipation definition in device is : SOT-23-3, SOT-23-5 400 350 SC 70-5 300 250 200 150 100 50 0 0 25 50 75 100 125 Ambient Temperature (°C ) Figure 3. Derating Curve for Packages For recommended operating conditions specification of RT9198T, where T J(MAX) is the maximum junction temperature of the die (125°C) and TA is the maximum ambient temperature. The junction to ambient thermal resistance (θJA is layout dependent) for SC-70 package is 333°C/W, 250°C/W is for SOT-23-3 and SOT-23-5 package 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 = 400 mW (SOT-23-3/ SOT-23-5) PD(MAX) = (125°C−25°C)/333 = 300 mW (SC-70-5) The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance θJA. For RT9198T packages, the Figure 3. of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. DS9198T-04 April 2011 www.richtek.com 9 RT9198T Outline Dimension H D L C B e A A1 b 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 0.508 0.014 0.020 C 2.591 2.997 0.102 0.118 D 2.692 3.099 0.106 0.122 e 1.803 2.007 0.071 0.079 H 0.080 0.254 0.003 0.010 L 0.300 0.610 0.012 0.024 SOT-23-3 Surface Mount Package www.richtek.com 10 DS9198T-04 April 2011 RT9198T 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 DS9198T-04 April 2011 www.richtek.com 11 RT9198T H D L B C b A A1 e Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 0.800 1.100 0.031 0.044 A1 0.000 0.100 0.000 0.004 B 1.150 1.350 0.045 0.054 b 0.150 0.400 0.006 0.016 C 1.800 2.450 0.071 0.096 D 1.800 2.250 0.071 0.089 e 0.650 0.026 H 0.080 0.260 0.003 0.010 L 0.210 0.460 0.008 0.018 SC-70-5 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. www.richtek.com 12 DS9198T-04 April 2011