RT9261B-33GB

RT9261B VFM Step-Up DC/DC Converter General Description Features The RT9261B Series are VFM Step-up DC/DC converter ICs with ultra low supply current by CMOS process and suitable for use with battery-powered instruments. z The RT9261B IC consists of an oscillator, a VFM control circuit, a driver transistor (LX switch), a reference voltage unit, an error amplifier, resistors for voltage detection, and a LX switch protection circuit. A low ripple and high efficiency step-up DC/DC converter can be constructed with the RT9261B IC and only three external components. z z z z z z z The EN pin enables the circuit to set the standby supply current at a maximum of 0.5μA. Ordering Information RT9261BPackage Type B : SOT-23-5 X : SOT-89 Lead Plating System P : Pb Free G : Green (Halogen Free and Pb Free) Output Voltage 15 : 1.5V 16 : 1.6V : 49 : 4.9V 50 : 5.0V z z Minimal Number of External Components (Only an Inductor, a Diode, and a Capacitor) Ultra Low Input Current (6.5μ μA at Switch Off) Capable of Supplying 50mA Output Current with Internal Switch ± 2% Output Voltage Accuracy Low Ripple and Low Noise Low Start-up Voltage, 0.8V at 1mA 80% Efficiency with Low Cost Inductor +50 ppm/°C Low Temperature-Drift SOT-89 and SOT-23-5 Small Packages RoHS Compliant and 100% Lead (Pb)-Free Applications z z z Power source for battery-powered equipment Power source for cameras, camcorders, VCRs, PDAs, pagers, electronic data banks, and hand-held communication equipment Power source for appliances, which require higher voltage than that of batteries used in the appliances Pin Configurations (TOP VIEW) LX GND 5 4 Note : Richtek products are : ` ments of IPC/JEDEC J-STD-020. ` 2 RoHS compliant and compatible with the current require- 3 EN VOUT NC 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. 1 2 GND VOUT (TAB) 3 LX SOT-89 DS9261B-16 April 2011 www.richtek.com 1 RT9261B Typical Application Circuit D1 1N5819 L1 VIN + RT9261B LX VOUT GND VOUT COUT 22µF D1 1N5819 L1 VIN EN RT9261B VOUT + LX GND VOUT COUT 22µF * L1 ranges from 27μH to 120μH Functional Pin Description Pin No. Pin N ame Pin Function SOT-23-5 SOT-89 1 -- EN C hip Enable (Active High). 2 2 VOUT Output Voltage. 3 -- NC N o Internal Connection. 4 1 GND Ground. 5 3 LX Pin for Switching. Function Block Diagram VLX Limiter LX VREF LXSW Buffer VOUT GND OSC 190kHz + Error Amplifier Chip Enable EN www.richtek.com 2 DS9261B-16 April 2011 RT9261B Absolute Maximum Ratings z z z z z z z z z Output Voltage -----------------------------------------------------------------------------------------------------LX Pin Voltage ------------------------------------------------------------------------------------------------------EN Pin Voltage(1) ---------------------------------------------------------------------------------------------------LX Pin Output Current --------------------------------------------------------------------------------------------Power Dissipation, PD @ TA = 25°C SOT-89 ---------------------------------------------------------------------------------------------------------------SOT-23-5 -------------------------------------------------------------------------------------------------------------Package Thermal Resistance SOT-89, θJC ---------------------------------------------------------------------------------------------------------SOT-89, θJA ---------------------------------------------------------------------------------------------------------SOT-23-5, θJA -------------------------------------------------------------------------------------------------------Operating Temperature Range ----------------------------------------------------------------------------------Storage Temperature Range -------------------------------------------------------------------------------------Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------ 8V 8V −0.3 to VOUT +0.3V 400mA 0.5W 0.25W 100° C/W 300° C/W 250° C/W −20 to +85° C −65° C to 150° C 260°C Notes: (1) Applicable to RT9261B-xxCB Electrical Characteristics (Refer to Figure 1) Parameter Symbol Test Conditions Min Typ Max Unit Output Voltage Accuracy ΔV OUT -2 -- +2 % Input Voltage VIN -- -- 7 V Start-up Voltage Hold-on Voltage VST VHO -0.7 0.8 -- 1 -- V V -- 24 36 -- 36 45 μA -- 6.5 10 μA μA VIN in continuous V OU T ≤ 3.5V (1) switching 3.5V < VOUT ≤ 5V Input Current 1 Input Current 2 IOUT = 1mA, V IN: 0 → 2V IOUT = 1mA, V IN: 2 → 0V (1) (2) (2) VOUT in switch off condition Input Current 3 (guaranteed by I1 and I2) V OUT ≤ 3.5V (1) -- 18 36 3.5V < VOUT ≤ 5V V OUT ≤ 3.5V (1) (2) -120 20 -- 45 -- 3.5V < VOUT ≤ 5V (2) 160 -- -- -- -- 0.5 μA VOUT = 2.5V to 5V 140 190 240 kHz VOUT = 1.5V to 2.4V 140 190 320 kHz 65 60 75 70 85 80 % % -- 80 -- % 0.65 0.8 1.0 V VIN in no load LX Switching Current ISWITCHING VLX = 0.4V LX Leakage Current ILEAKAGE Maximum Oscillator Frequency FMAX Oscillator Duty Cycle DOSC VLX = 6V On (V LX “L”) side V OUT = 2.5V to 5V V OUT = 1.5V to 2.4V Efficiency V LX Voltage Limit LX switch on mA Notes: (1) VIN = 1.8V, VSS = 0V, IOUT = 1mA, Topt = 25° C, and use External Circuit of Typical Application (2) VIN = 3V, VSS = 0V, IOUT = 1mA, Topt= 25°C, and External Circuit of Typical Application DS9261B-16 April 2011 www.richtek.com 3 RT9261B Electrical Characteristics (Refer to Figure 2) Parameter Output Voltage Accuracy Input Voltage Start-up Voltage Hold-on Voltage Efficiency Symbol ΔV OUT VIN VST VHO Test Conditions IOUT = 1mA, V IN: 0 → 2V IOUT = 1mA, V IN: 2 → 0V (1) VIN in continuous V OU T ≤ 3.5V switching 3.5V < VOUT ≤ 5V VOUT in switch off condition Input Current 1 Input Current 2 (1 ) (2) Input Current 3 (guaranteed by I1 and I2) VIN in no load LX Switching Current ISWITCHING VLX = 0.4V LX Leakage Current ILEAKAGE VIN = V OUT * 0.9 EN “L” Level EN “H” Input Current EN “ L” Input Current VIN = V OUT * 0.9 EN = V OUT EN = 0V Oscillator Duty Cycle VLX Voltage Limit DOSC Typ Max Unit −2 --0.7 ----- --0.8 -80 24 36 6.5 +2 7 1 --36 45 10 % V V V % -- 18 36 -120 160 -0.4 x V OUT --−0.5 20 ---- 45 --0.5 mA -- -- V ---- 0.2 0.5 -- V μA μA (1) 3.5V < VOUT ≤ 5V VOUT ≤ 3.5V (1) 3.5V < VOUT ≤ 5V (2) (2) VLX = 6V EN “H” Level Maximum Oscillator Frequency FMAX VOUT ≤ 3.5V (2) Min μA μA μA μA VOUT = 2.5V to 5V 140 190 240 kHz VOUT = 1.5V to 2.4V 140 190 320 kHz 65 75 85 % 60 0.65 70 0.8 80 1.0 % V On (VLX “L”) side VOUT = 2.5V to 5V VOUT = 1.5V to 2.4V LX switch on Notes: (1) VIN = 1.8V, VSS = 0V, IOUT = 1mA, Topt = 25°C, and use External Circuit of Typical Application (2) VIN = 3V, VSS = 0V, IOUT = 1mA, Topt= 25°C, and External Circuit of Typical Application www.richtek.com 4 DS9261B-16 April 2011 RT9261B Start-up/Hold-on Voltage vs. Output Current Output Voltage vs. Output Current 2.5 4.0 3.0V 2.5V 3.5 2 Output Voltage (V) 1 Start-up/Hold-on Voltage Vstart/Vhold (V)1 Typical Operating Characteristics 1.5 Vstart 1 Vhold 0.5 VOUT = 3.3V L = 47μH 3.0 2.0V 1.5V 1.0V 2.5 2.0 1.5 1.0 VOUT = 3.3V L = 47μH 0.5 0 0.0 0 30 60 90 120 150 0 180 50 Output Current (mA) 100 150 200 Output Current (mA) Output Current vs. Ripple Voltage Output Current vs. Ripple Voltage 90 300 2.5V 3.0V 250 2.0V 3.0V 200 150 1.5V 100 VOUT = 3.3V COUT = 20μF L = 47μH 50 1.0V Ripple Voltage (mVp-p)1 Ripple Voltage (mVp-p) 1 80 70 2.0V 60 2.5V 50 40 30 1.5V 20 10 0 VOUT = 3.3V COUT = 68μF L = 47μH 1.0V 0 0 50 100 150 0 200 50 Output Current (mA) 100 150 Efficiency vs. output Current Output Current vs. Ripple Voltage 90 25 3.0V 2.5V 70 2.5V 3.0V 15 10 1.0V VOUT = 3.3V COUT = 170μF L = 47μH 5 2.0V 1.5V 0 0 50 1.0V 2.0V 1.5V 60 50 40 30 20 VOUT = 3.3V L = 47μH 10 0 100 150 Output Current (mA) DS9261B-16 April 2011 Efficiency (%)1 Ripple Voltage (mVp-p)1 80 20 200 Output Current (mA) 200 0 50 100 150 200 Output Current (mA) www.richtek.com 5 Start-up/Hold-on Voltage vs. Output Current Output Voltage vs. Output Current 2.5 4.0 3.0V 3.5 2 Output Voltage (V) 1 Start-up/Hold-on Voltage Vstart/Vhold (V)1 RT9261B 1.5 Vstart 1 Vhold 0.5 VOUT = 3.3V L = 100μH 1.5V 3.0 2.5 2.0 1.5 1.0 VOUT = 3.3V L = 100μH 0.5 0 0.0 0 20 40 60 80 100 0 120 50 Output Current (mA) Output Current vs. Ripple Voltage 200 Output Current vs. Ripple Voltage 3.0V 250 200 2.5V 150 100 VOUT = 3.3V COUT = 20μF L = 100μH 50 1.5V 1.0V 0 0 50 2.5V 80 Ripple Voltage (mVp-p) 1 Ripple Voltage (mVp-p) 1 150 90 2.0V 70 60 50 3.0V 40 30 20 2.0V 1.5V 0 100 150 VOUT = 3.3V COUT = 68μF L = 100μH 1.0V 10 0 200 50 Output Current (mA) 100 150 Efficiency vs. output Current 100 2.5V 90 16 3.0V Efficiency (%) 1 12 1.0V 8 6 4 2 VOUT = 3.3V COUT = 170μF L = 100μH 1.5V 3.0V 80 2.0V 14 200 Output Current (mA) Output Current vs. Ripple Voltage 18 Ripple Voltage (mVp-p) 1 100 Output Current (mA) 300 10 2.5V 2.0V 1.0V 1.0V 70 2.5V 2.0V 1.5V 60 50 40 30 20 VOUT = 3.3V L = 100μH 10 0 0 0 50 100 150 Output Current (mA) www.richtek.com 6 200 0 50 100 150 200 Output Current (mA) DS9261B-16 April 2011 RT9261B 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 DS9261B-16 April 2011 www.richtek.com 7 RT9261B D D1 A B C C1 e e H A b b1 b Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 1.397 1.600 0.055 0.063 b 0.356 0.483 0.014 0.019 B 2.388 2.591 0.094 0.102 b1 0.406 0.533 0.016 0.021 C 3.937 4.242 0.155 0.167 C1 0.787 1.194 0.031 0.047 D 4.394 4.597 0.173 0.181 D1 1.397 1.753 0.055 0.069 e 1.448 1.549 0.057 0.061 H 0.356 0.432 0.014 0.017 3-Lead SOT-89 Surface Mount 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: marketing@richtek.com 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 8 DS9261B-16 April 2011