RT9001

RT9001 RICHTEK | Alldatasheet

Document overview

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Technical content

Features

zzzzz Low Quiescent Current (Typically 220μμμμμA) zzzzz Guaranteed 600mA Output Current zzzzz Low Dropout Voltage : 580mV at 600mA zzzzz Wide Operating Voltage Ranges : 3V to 5.5V zzzzz Ultra-Fast Transient Response zzzzz Tight Load and Line Regulation zzzzz Current Limiting Protection zzzzz Thermal Shutdown Protection zzzzz Only low-ESR Ceramic Capacitor Required for Stability zzzzz Custom Voltage Available zzzzz RoHS Compliant and 100% Lead (Pb)-Free

Applications

z CD/DVD-ROM, CD/RW z Wireless LAN Card/Keyboard/Mouse z Battery-Powered Equipment z XDSL Router z PCMCIA Card (TOP VIEW) 1 2 3 GND VOUT (TAB) VIN SOT-223 Note : RichTek Pb-free and Green products are : \RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. \Suitable for use in SnPb or Pb-free soldering processes. \`100%matte tin (Sn) plating. RT9001- Package Type G : SOT-223 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commer- cial Standard) Output Voltage 12 : 1.2V 13 : 1.3V 45 : 4.5V

DS9001-04 March 2007www.richtek.com Typical Application Circuit Functional Pin Description Function Block Diagram Note: To prevent oscillation, a 1μμμμμF minimum X7R or X5R dielectric is strongly recommended if ceramics are used as input/output capacitors. When using the Y5V dielectric, the minimum value of the input/output capacitance that can be used for stable over full operating temperature range is 3.3μμμμμF. (see Application Information Section for further details) Pin Name Pin Function VIN Supply Input VOUT Regulator Output GND Common Ground Current Limiting Sensor Thermal Shutdown Error Amplifier 1.2V Reference VIN GND VOUT VIN GND VOUT RT9001 COUT 1uF CIN 1uF VIN VOUT

DS9001-04 March 2007 www.richtek.com

Electrical Characteristics

Absolute Maximum Ratings (Note 1) z Power Dissipation, PD @ TA = 25°C z Package Thermal Resistance (Note 7) z ESD Susceptibility (Note 2) Recommended Operating Conditions (Note 3) (VIN = VOUT + 1V or VIN = 2.8V whichever is greater, CIN = 1μF, COUT = 1μF, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Units Output Voltage Accuracy ΔVOUT I OUT = 1mA −1 -- +3 % Current Limit I LIM R LOAD = 1Ω 600 -- -- mA Quiescent Current (Note 6) I Q I OUT = 0mA -- 220 300 μA Dropout Voltage (Note 4) V DROP I OUT = 600mA -- 580 -- mV Line Regulation ΔVLINE VIN = (VOUT + 0.3V) to 5.5V, IOUT = 1mA -- 0.2 -- %/V Load Regulation (Note 5) ΔVLOAD 1mA < IOUT < 600mA -- 30 55 mV Power Supply Rejection Rate PSRR f = 1kHz, C OUT = 1μF -- −55 -- dB Thermal Shutdown Temperature T SD -- 170 -- °C Thermal Shutdown Hysteresis ΔTSD -- 40 -- °C 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. Devices are ESD sensitive. Handling precaution recommended. Note 3. The device is not guaranteed to function outside its operating conditions. Note 4.The dropout voltage is defined as V IN -VOUT, which is measured when V OUT is V OUT(NORMAL) − 100mV. Note 5. Regulation is measured at constant junction temperature by using a 20ms current pulse. Devices are tested for load regulation in the load range from 1mA to 600mA respectively. Note 6. Quiescent, or ground current, is the difference between input and output currents. It is defined by I Q = IIN - IOUT under no load condition (I OUT = 0mA). The total current drawn from the supply is the sum of the load current plus the ground pin current. Note 7. θ JA is measured in the natural convection at T A = 25 °C on a low effective thermal conductivity test board of JEDEC 51-3 thermal measurement standard.

DS9001-04 March 2007www.richtek.com Typical Operating Characteristics Power Supply Rejection Ratio -60 -50 -40 -30 -20 -10 Frequency (Hz) PSRR (dB) VIN = 5V CIN = 1uF COUT = 1uF 100mA 1mA 10 100 1k 10k 100k 1M Current Limit vs. Input voltage 700 750 800 850 900 33 . 544 . 555 . 5 Input voltage (V) Current Limit (mA)VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω Current Limit vs. Temperature 700 750 800 850 900 -50 -25 0 25 50 75 100 125 Temperature Current Limit (mA)VIN = 5V CIN = 1uF COUT = 1uF RL = 0.5Ω (°C) -40 Dropout Voltage vs. Load Current 100 200 300 400 500 600 700 0 100 200 300 400 500 600 Load Current (mA) Dropout Voltage (mV) CIN = 1uF COUT = 1uF TJ = 125°C TJ = 25°C TJ = −40°C Output Voltage vs. Temperature 3.1 3.15 3.2 3.25 3.3 3.35 3.4 3.45 3.5 -50 -25 0 25 50 75 100 125 Temperature Output Voltage (V) (°C) Quiescent Current vs. Temperature 150 170 190 210 230 250 -50 -25 0 25 50 75 100 125 Temperature Quiescent Current (uA) VIN = 5V (°C)

DS9001-04 March 2007 www.richtek.com Load Transient Response Time (100us/Div) Load Current (mA) 200 100 Output Voltage Deviation (mV) -20 VIN = 5V, ILOAD = 1 to 150mA CIN = COUT = 1uF (Ceramic, X7R) Line Transient Response Time (100us/Div) Output Voltage Deviation (mV) -20 Input Voltage Deviation (V) VIN = 4 to 5V CIN = 1uF COUT = 1uF Output Noise Output Noise Signal (μV) Time (1ms/DIV) 400 200 -200 -400 VIN = 5V CIN = 1uF ILOAD = 100mA COUT = 1uF f = 10Hz to 100kHz Region of Stable COUT ESR vs. Load Current 0.00 0.01 0.10 1.00 10.00 100.00 0 100 200 300 400 500 600 Load Current (mA) COUT ESR (Ω) Instable Instable Stable COUT = 1uF to 4.7uF

DS9001-04 March 2007www.richtek.com

Application Information

Like any low-dropout regulator, the RT9001 series requires input and output decoupling capacitors. These capacitors must be correctly selected for good performance (see Capacitor Characteristics Section). Please note that linear regulators with a low dropout voltage have high internal loop gains which require care in guarding against oscillation caused by insufficient decoupling capacitance. Input Capacitor An input capacitance of ≅ 1μF is required between the device input pin and ground directly (the amount of the capacitance may be increased without limit). The input capacitor MUST be located less than 1 cm from the device to assure input stability. A lower ESR capacitor allows the use of less capacitance, while higher ESR type (like aluminum electrolytic) require more capacitance. Capacitor types (aluminum, ceramic and tantalum) can be mixed in parallel, but the total equivalent input capacitance/ ESR must be defined as above to stable operation. There are no requirements for the ESR on the input capacitor, but tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance will be ≅ 1 μF over the entire operating temperature range. Output Capacitor The RT9001 is designed specifically to work with very small ceramic output capacitors. The recommended minimum capacitance (temperature characteristics X7R or X5R) is from 1μF to 4.7μF ceramic capacitor between LDO output and GND for transient stability, but it may be increased without limit. Higher capacitance values help to improve transient. The output capacitor's ESR is critical because it forms a zero to provide phase lead which is required for loop stability. (When using the Y5V dielectric, the minimum value of the input/output capacitance that can be used for stable over full operating temperature range is 3.3μF.) No Load Stability The device will remain stable and in regulation with no external load. This is specially important in CMOS RAM keep-alive applications. Input-Output (Dropout) Voltage A regulator's minimum input-to-output voltage differential (dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this determines the useful end-of-life battery voltage. Because the device uses a PMOS, its dropout voltage is a function of drain-to-source on-resistance, R DS(ON), multiplied by the load current : VDROPOUT = VIN - VOUT = RDS(ON) x IOUT Current Limit The RT9001 monitors output current and controls the PMOS' gate voltage to limit the output current to 600mA (MIN). The output can be shorted to ground for an indefinite period of time without damaging the part. Short-Circuit Protection The device is short circuit protected and in the event of a peak over-current condition, the short-circuit control loop will rapidly drive the output PMOS pass element off. Once the power pass element shuts down, the control loop will rapidly cycle the output on and off until the average power dissipation causes the thermal shutdown circuit to respond to servo the on/off cycling to a lower frequency. Please refer to the section on thermal information for power dissipation calculations. Capacitor Characteristics It is important to note that capacitance tolerance and variation with temperature must be taken into consideration when selecting a capacitor so that the minimum required amount of capacitance is provided over the full operating temperature range. In general, a good tantalum capacitor will show very little capacitance variation with temperature, but a ceramic may not be as good (depending on dielectric type). No Load Stability The device will remain stable and in regulation with no external load. This is specially important in CMOS RAM keep-alive applications. Aluminum electrolytics also typically have large temperature variation of capacitance value.

DS9001-04 March 2007 www.richtek.com Equally important to consider is a capacitor's ESR change with temperature: this is not an issue with ceramics, as their ESR is extremely low. However, it is very important in Tantalum and aluminum electrolytic capacitors. Both show increasing ESR at colder temperatures, but the increase in aluminum electrolytic capacitors is so severe they may not be feasible for some applications. Ceramic: For values of capacitance in the 10 μF to 100μF range, ceramics are usually larger and more costly than tantalums but give superior AC performance for by-passing high frequency noise because of very low ESR (typically less than 10mΩ). However, some dielectric types do not have good capacitance characteristics as a function of voltage and temperature. Z5U and Y5V dielectric ceramics have capacitance that drops severely with applied voltage. A typical Z5U or Y5V capacitor can lose 60% of its rated capacitance with half of the rated voltage applied to it. The Z5U and Y5V also exhibit a severe temperature effect, losing more than 50% of nominal capacitance at high and low limits of the temperature range. X7R and X5R dielectric ceramic capacitors are strongly recommended if ceramics are used, as they typically maintain a capacitance range within ±20% of nominal over full operating ratings of temperature and voltage. Of course, they are typically larger and more costly than Z5U/Y5U types for a given voltage and capacitance. Tantalum: Solid tantalum capacitors are recommended for use on the output because their typical ESR is very close to the ideal value required for loop compensation. They also work well as input capacitors if selected to meet the ESR requirements previously listed. Tantalums also have good temperature stability: a good quality tantalum will typically show a capacitance value that varies less than 10~15% across the full temperature range of 125°C to -40°C. ESR will vary only about 2X going from the high to low temperature limits. The increasing ESR at lower temperatures can cause oscillations when marginal quality capacitors are used (if the ESR of the capacitor is near the upper limit of the stability range at room temperature). Aluminum: This capacitor type offers the most capacitance for the money. The disadvantages are that they are larger in physical size, not widely available in surface mount, and have poor AC performance (especially at higher frequencies) due to higher ESR and ESL. Compared by size, the ESR of an aluminum electrolytic is higher than either Tantalum or ceramic, and it also varies greatly with temperature. A typical aluminum electrolytic can exhibit an ESR increase of as much as 50X when going from 25°C down to −40°C. It should also be noted that many aluminum electrolytics only specify impedance at a frequency of 120Hz, which indicates they have poor high frequency performance. Only aluminum electrolytics that have an impedance specified at a higher frequency (between 20kHz and 100kHz) should be used for the device. Derating must be applied to the manufacturer's ESR specification, since it is typically only valid at room temperature. Any applications using aluminum electrolytics should be thoroughly tested at the lowest ambient operating temperature where ESR is maximum. Thermal Considerations Thermal protection limits power dissipation in RT9901. When the operation junction temperature exceeds 170°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 40°C. For continuous loading operation, do not exceed absolute maximum operation junction temperature 125 °C. The power dissipation definition in device is: PD = (VIN - VOUT) IOUT + VIN IGND The final operating junction temperature for any set of conditions can be estimated by the following thermal equation : P D (MAX) = ( TJ (MAX) - TA ) / θJA

DS9001-04 March 2007www.richtek.com Where TJ(MAX) is the maximum junction temperature of the die (125°C) and TA is the ambient temperature. The junction to ambient thermal resistance (θJA) for SOT-223 package at recommended minimum footprint is 160 °C/W (θJA is layout dependent). Visit our website in whic h “Recommended Footprints for Soldering Surface Mount Packages” for detail.

DS9001-04 March 2007 www.richtek.com Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 Richtek Technology Corporation Taipei Office (Marketing) 8F, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek.com Outline Dimension Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 1.450 1.803 0.057 0.071 A1 0.020 0.100 0.0008 0.0047 b 0.610 0.787 0.024 0.031 B 3.302 3.708 0.130 0.146 C 6.706 7.290 0.264 0.287 D 6.299 6.706 0.248 0.264 D1 2.896 3.150 0.114 0.124 e 2.261 2.362 0.089 0.093 H 0.229 0.330 0.009 0.013 L 1.550 1.950 0.061 0.077 L1 0.800 1.100 0.009 0.013 3-Lead SOT-223 Surface Mount Package A b H B D C L e e