RT9266GX5

RT9266 Tiny Package, High Efficiency, Step-up DC/DC Converter General Description The RT9266 is a compact, high efficiency, and low voltage step-up DC/DC converter with an Adaptive Current Mode PWM control loop, includes an error amplifier, ramp generator, comparator, switch pass element and driver in which providing a stable and high efficient operation over a wide range of load currents. It operates in stable waveforms without external compensation. The low start-up input voltage below 1V makes RT9266 suitable for 1 to 4 battery cells applications of providing up to 300mA output current. The 450kHz high switching rate minimized the size of external components. Besides, the 17µA low quiescent current together with high efficiency maintains long battery lifetime. The output voltage is set with two external resistors. Both internal 2A switch and driver for driving external power devices (NMOS or NPN) are provided. Features l l l l l l l l l 1.0V Low Start-up Input Voltage High Supply Capability to Deliver 3.3V 100mA with 1 Alkaline Cell 17µA Quiescent (Switch-off) Supply Current Zero Shutdown Mode Supply Current 90% Efficiency 450kHz Fixed Switching Frequency Providing Flexibility for Using Internal and External Power Switches Small SOT-23-6 & SOT-89-5 Package RoHS Compliant and 100% Lead (Pb)-Free Applications l l l l l Ordering Information RT9266 Package Type E : SOT-23-6 X5 : SOT-89-5 Operating Temperature Range P : Pb Free with Commercial Standard G : Green (Halogen Free with Commercial Standard) l l PDA DSC LCD Panel RF-Tags MP3 Portable Instrument Wireless Equipment Pin Configurations (TOP VIEW) GND FB VDD 5 2 LX 4 3 5 4 LX Note : RichTek Pb-free and Green products are : }RoHS compliant and compatible with the current requirements of IPC/JEDEC J-STD-020. }Suitable for use in SnPb or Pb-free soldering processes. }100% matte tin (Sn) plating. 6 1 EN 1 2 3 EXT GND EN VDD FB SOT-23-6 SOT-89-5 Marking Information For marking information, contact our sales representative directly or through a RichTek distributor located in your area, otherwise visit our website for detail. Note : There is no pin1 indicator on top mark for SOT-23-6 type, and pin 1 will be lower left pin when reading top mark from left to right. DS9266-12 May 2007 www.richtek.com 1 RT9266 Typical Application Circuit L1 VIN + EN EXT C3 100uF 3.3 to 10 uH D1 1N5819 VOUT 3.3V/5V R1 1.6M/3M + C1 100uF C2 1uF VDD RT9266 GND LX FB R2 980k/1M Figure 1. RT9266 Typical Application for Portable Instruments 3.1V to 5V for 12V 2.8V to 5V for 9V VIN + C4 100uF RVDD 100 VDD EN RT9266 GND EXT LX FB L1 4.7uH D1 1N5819 CVDD 1uF Q1 N MOS R1 C3 0.1uF 860k/620k + RM 0.22 R2 100k C2 1uF 12V/9V 300mA C1 100uF Figure 2. RT9266 High Voltage Applications www.richtek.com 2 DS9266-12 May 2007 RT9266 L1 VIN + EN C3 100uF 3.3 to 10 uH D1 1N5819 VOUT 3.3V/5V C2 1uF VDD LX Q1 N MOS R1 1.6M/3M + C1 100uF RT9266 EXT GND FB R2 980k/1M Figure 3. RT9266 for Higher Current Applications L1 VIN 3.3V/5V C1 1uF Q1 VDD EN RT9266 GND LX FB EXT R2 100k C5 10uF N MOS C6 C7 1uF 0.1uF R1 620k C4 10uF R3 100 C2 1uF 4.7uH C8 1uF C3 10uF VOUT2 +18V 10mA VOUT1 +9V 10mA VOUT3 -9V 10mA Figure 4. RT9266 for Multi-Output Applications DS9266-12 May 2007 www.richtek.com 3 RT9266 Test Circuit I (VIN) VIN L1 C3 100uF 10uH + D1 1N5819 VOUT 3.3V/5V + R1 1.6M/3M LX FB R2 980k/1M C4 102 C1 100uF C5 106 A A I (VDD) VDD EN EXT RT9266 GND C2 1uF Functional Pin Description Pin No. RT9266CX5 1 -5 4 2 3 R T9266CE 1 2 3 4 5 6 EN EXT GND LX VDD FB Chip Enable (Active High) Output Pin for Driving External NMOS Ground Pin for Switching Input Positive Power Pin of RT9266 Feedback Input Pin Internal Reference Voltage for the Error Amplifier is 1.25V. Pin Name Pin Function Function Block Diagram EXT VDD RT9266 LX FB 1.25V VDD R2 Shut Down EN Q2 N MOS Over Temp. Detector + Loop Control Circuit Q1 N MOS R1 GND www.richtek.com 4 DS9266-12 May 2007 RT9266 Absolute Maximum Ratings l l l l l l l l Supply Voltage --------------------------------------------------------------------------------------------------- −0.3V to 7V LX Pin Switch Voltage ------------------------------------------------------------------------------------------ −0.3V to 7V Other I/O Pin Voltages ------------------------------------------------------------------------------------------ −0.3V to (VDD + 0.3V) LX Pin Switch Current ------------------------------------------------------------------------------------------- 2.5A EXT Pin Driver Current ------------------------------------------------------------------------------------------ 200mA Package Thermal Resistance SOT-23-6, θJC ----------------------------------------------------------------------------------------------------- 145°C/W SOT-89-5, θJC ----------------------------------------------------------------------------------------------------- 45°C/W Operating Junction Temperature ------------------------------------------------------------------------------ 125°C Storage Temperature Range ----------------------------------------------------------------------------------- −65°C to +150°C NOTE: Absolute Maximum ratings are threshold limit values that must not be exceeded even for an instant under any conditions. Moreover, such values for any two items must not be reached simultaneously. Operation above these absolute maximum ratings may cause degradation or permanent damage to the device. These are stress ratings only and do not necessarily imply functional operation below these limits Electrical Characteristics (VIN = 1.5V, VDD set to 3.3V, Load Current = 0, TA = 25° C, unless otherwise specified) Parameter Start-UP Voltage Operating VDD Range Shutdown Current I (V IN) Switch-off Current I (VDD) Continuous Switching Current No Load Current I (V IN) Feedback Reference Voltage Switching Frequency Maximum Duty LX ON Resistance Current Limit Setting EXT ON Resistance to VDD EXT ON Resistance to GND Line Regulation Load Regulation EN Pin Trip Level Temperature Stability for Vout Thermal Shutdown Hysterises Symbol VST VDD IOFF IL = 1mA Test Conditions Min -2 --0.4 -1.225 425 85 -1.6 ----0.4 --- Typ 0.98 -0.01 17 0.55 75 * Max 1.05 6 1 25 0.7 -1.275 575 -1.1 2.6 ** Units V V µA µA mA µA V kHz % Ω A Ω Ω mV/V mV/mA V ppm/°C °C VDD pin voltage EN Pin = 0V, VIN = 4.5V ISWITCH OFF VIN = 6V ISWITCH INO LOAD VREF FS DMAX VIN = EN = 3.3V, VFB = GND VIN = 1.5V, VOUT = 3.3V Close Loop, VDD = 3.3V VDD = 3.3V VDD = 3.3V VDD = 3.3V ILIMIT VDD = 3.3V VDD = 3.3V VDD = 3.3V ∆VLINE ∆VLOAD VIN = 3.5 ~ 6V, IL = 1mA VIN = 2.5V, IL = 1 ~ 100mA VDD = 3.3V TS ∆TSD 1.25 500 95 0.3 2 5 5 1.5 0.25 *** 8.5 8.5 10 -1.2 --- 0.8 50 10 DS9266-12 May 2007 www.richtek.com 5 RT9266 Note : * No Load Current is highly dependent on practical system design and component selection that cannot be covered by production testing. Typical No Load Current is verified by typical application circuit with recommended components. No Load Current performance is guaranteed by Switch Off Current and Continuous Switching Current. ** Current Limit is guaranteed by design at TA = 25°C. ***Load Regulation is not tested at production due to practical instrument limitation. Load Regulation performance is dominantly dependent on DC loop gain and LX ON Resistance that are guaranteed by “ Line Regulation” and “ LX ON Resistance” tests in production. www.richtek.com 6 DS9266-12 May 2007 RT9266 Typical Operating Characteristics (Refer to Test Circuit) Efficiency vs. Output Current 95 Efficiency vs. Output Current 95 VOUT = 5V, TA = 25°C 90 VOUT = 3.3V, TA = 25°C 90 Efficie ncy (%) Efficien cy (%) 85 VIN = 4.0V VIN = 3.5V VIN = 3.0V VIN = 85 VIN = 80 80 VIN = 2.5V VIN = 2.0V VIN = 2.0V 75 75 VIN = 1.5V VIN = 1.0V VIN = 1.5V 70 000 001 010 100 1000 70 0.1 1 10 100 1000 Output Current (mA) Output Current (mA) Input Current I(VDD) vs. Output Current 250 21 Input Current I(VDD ) vs. Input Voltage VOUT = 5V @ no load 20 VIN = 3V, VOUT = 5V 200 Inp ut Curre nt ( µ A) Inp ut Current ( µ A) 0.01 0.1 1 10 100 1000 19 18 17 16 15 2.5 3.0 3.5 4.0 4.5 5.0 150 100 50 0 Output Current (mA) Input Voltage (V) Supply Current I(VIN) vs. Input Voltage 180 VOUT = 5V @ no load 150 90 Supply Current I(VIN) vs. Input Voltage VOUT = 3.3V @ no load 80 Supply Current ( µ A) 1 Supply Current ( µ A) 120 90 60 30 0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 70 60 50 40 30 1.5 2 2.5 3 3.5 Input Voltage (V) DS9266-12 May 2007 Input Voltage (V) www.richtek.com 7 RT9266 Switching Swichting Frequency vs. VDD Pin Voltage 600 1.6 Start Up Voltage vs. Output Current VOUT = 3.3V 1.4 SwitwhchgnRa te Fuequy nkHzKHz). S c it in i g Freq r enc e (c y () VIN = 2.4V to 2.8V VIN = 3V to 5.6V Sta rt Up Volta ge (V) 500 1.2 1.0 0.8 0.6 0.4 0.2 400 300 VIN = 1.2V to 2.2V 200 (In C.R. mode) 100 0 1 2 3 4 5 6 0.0 0 30 60 90 120 150 180 210 VDD Pin Voltage (V) Output Current (mA) LX & Output Ripple VIN = 1V, VOUT = 3.3V @ 100mA LX & Output Ripple VIN = 1V, VOUT = 3.3V @ 10mA LX Ou tpu t R ipp le Time (1 µs/Div) Ou tpu t R ipp le LX Time (1 µs/Div) LX & Output Ripple VIN = 2V, VOUT = 3.3V @ 200mA LX & Output Ripple VIN = 2V, VOUT = 3.3V @ 10mA LX Ou tpu t R ipp le Time (1 µs/Div) Ou tpu t R ipp le LX Time (1 µs/Div) www.richtek.com 8 DS9266-12 May 2007 RT9266 LX & Output Ripple VIN = 3V, VOUT = 3.3V @ 200mA LX & Output Ripple VIN = 3V, VOUT = 3.3V @ 10mA LX Ou tpu t R ipp le Ou tpu t R ipp le LX Time (1 µs/Div) Time (1 µs/Div) LX & Output Ripple VIN = 2V, VOUT = 5V @ 200mA LX & Output Ripple VIN = 2V, VOUT = 5V @ 20mA LX Ou tpu t R ipp le Time (1 µs/Div) Ou tpu t R ipp le LX Time (1 µs/Div) LX & Output Ripple VIN = 3V, VOUT = 5V @ 200mA LX & Output Ripple VIN = 3V, VOUT = 5V @ 20mA LX Ou tpu t R ipp le Time (1 µs/Div) Ou tpu t R ipp le LX Time (1 µs/Div) DS9266-12 May 2007 www.richtek.com 9 RT9266 LX & Output Ripple VIN = 4.5V, VOUT = 5V @ LX & Output Ripple VIN = 4.5V, VOUT = 5V @ 20mA LX Ou tpu t R ipp le Time (1 µs/Div) Ou tpu t R ipp le LX Time (1 µs/Div) Transient Response VIN = 2V, VOUT = 3.3V IOUT = 10mA 200mA Transient Response VIN = 3V, VOUT = 3.3V Ou tpu t Transien t Vo ltage Ou tpu t Transien t Vo ltage IOUT = 10mA 200mA Time (50 µs/Div) Time (50 µs/Div) Transient Response VIN = 3V, VOUT = 5V IOUT = 10mA 200mA Transient Response VIN = 4.5V, VOUT = 5V Ou tpu t Transien t Vo ltage Time (50 µs/Div) Ou tpu t Transien t Vo ltage IOUT = 10mA 200mA Time (50 µs/Div) www.richtek.com 10 DS9266-12 May 2007 RT9266 Output Voltage vs. Temperature 3.34 5 Output Voltage vs. Temperature VIN = 3V, VOUT = 5V, IOUT = 4.98 VIN = 1.8V, VOUT = 3.3V, IOUT = 3.32 Ou tput Volta ge(V ) 3.3 3.28 3.26 3.24 3.22 3.2 -40 -10 20 50 80 110 140 Outpu t Vo ltage (V) 4.96 4.94 4.92 4.9 4.88 4.86 4.84 -40 -10 20 50 80 110 140 Temperature (°C) Temperature (°C) DS9266-12 May 2007 www.richtek.com 11 RT9266 Application Information Output Voltage Setting Referring to Typical Application Circuits, the output voltage of the switching regulator (VOUT ) can be set with Equation (1). VOUT = ( 1+ R1 R2 ) × 1.25V Layout Guide l l A full GND plane without gap break. VDD to GND noise bypass − Short and wide connection for the 1µF MLCC capacitor between Pin5 and Pin3. VIN to GND noise bypass − Add a capacitor close to L1 inductor, when VIN is not an idea voltage source. Minimized FB node copper area and keep far away from noise sources. Minimized parasitic capacitance connecting to LX and EXT nodes, which may cause additional switching loss. (1) l Feedback Loop Design Referring to Typical Application Circuits. The selection of R1 and R2 based on the trade-off between quiescent current consumption and interference immunity is stated below: l l l l Board Layout Example (2-Layer Board) (Refer to Typical Application Circuits Figure 2 for the board) Follow Equation (1) Higher R reduces the quiescent current (Path current = 1.25V/R2), however resistors beyond 5MΩ are not recommended. Lower R gives better noise immunity, and is less sensitive to interference, layout parasitics, FB node leakage, and improper probing to FB pins. VOUT R1 FB Pin _ Q + R2 l Prober Parasitics l A proper value of feed forward capacitor parallel with R1 can improve the noise immunity of the feedback loops, especially in an improper layout. An empirical suggestion is around 0~33pF for feedback resistors of MΩ, and 10nF~0.1µF for feedback resistors of tens to hundreds kΩ. - Top Layer - For applications without standby or suspend modes, lower values of R1 and R2 are preferred. For applications concerning the current consumption in standby or suspend modes, the higher values of R1 and R2 are needed. Such “ high impedance feedback loops” are sensitive to any interference, which require careful layout and avoid any interference, e.g. probing to FB pin. - Bottom Layer www.richtek.com 12 DS9266-12 May 2007 RT9266 Outline Dimension H D L C B b A A1 e Symbol A A1 B b C D e H L Dimensions In Millimeters Min 0.889 0.000 1.397 0.250 2.591 2.692 0.838 0.080 0.300 Max 1.295 0.152 1.803 0.560 2.997 3.099 1.041 0.254 0.610 Dimensions In Inches Min 0.031 0.000 0.055 0.010 0.102 0.106 0.033 0.003 0.012 Max 0.051 0.006 0.071 0.022 0.118 0.122 0.041 0.010 0.024 SOT-23-6 Surface Mount Package DS9266-12 May 2007 www.richtek.com 13 RT9266 D D1 b1 A C B C1 e e H A b b1 b Symbol A b B b1 C C1 D D1 e H Dimensions In Millimeters Min 1.397 0.356 2.388 0.406 3.937 0.787 4.394 1.397 1.397 0.356 Max 1.600 0.508 2.591 0.533 4.242 1.194 4.597 1.702 1.600 0.432 D imensions In Inches Min 0.055 0.014 0.094 0.016 0.155 0.031 0.173 0.055 0.055 0.014 Max 0.063 0.020 0.102 0.021 0.167 0.047 0.181 0.067 0.063 0.017 5-Lead SOT-89 Surface Mount Package 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 www.richtek.com 14 DS9266-12 May 2007