PWM Controlled, Step-up DC/DC Converter in Tiny Package

1 1 FP6733fitipower integrated technology lnc. PWM Controlled, Step-up DC/DC Converter in Tiny Package Pin Assignments S6 Package (SOT-23-6) 213645(Marking)CEEXTGNDLXVDDFB S9 Package (TSOT-23-6) 213645(Marking)CEEXTGNDLXVDDFB Figure 2. Pin Assignment of fp6733 Ordering Information SOT-23-6 Marking Part Number Product Code FP6733S6P AA TSOT-23-6 Marking Part Number Product Code FP6733S9P aa Description The fp6733 is a high efficiency PWM DC/DC step -up Converter with internally compensated current mode controller. The output voltage is set with two external resistors. The 550kHz switching frequency minimizes the size of external components. Both internal 1A switch and driver for driving external power device (NMOS or NPN) are provided. The fp6733 starts up below 1V input voltage with 1mA load. Due to built-in automatic PWM/PFM switch-over function, the fp6733 is able to get high efficiency during both light and heavy load.

2 External transistor pin is available to accommodate high output current applications. The fp6733 is available in SOT-23-6 and TSOT-23-6 packages. Features (Typ.) Low Start-up Input Voltage at 1mA Load High Switching Frequency at 550kHz Providing Flexibility for Using Internal and External Power Switches Automatic PFM Mode at Light Load Low Ripple and High Efficiency Excellent Line/Load Regulation Chip Enable Control Function Current Limit Protection Thermal Overload Protection Space Saving Packages : SOT-23-6 and TSOT-23-6 Applications PDA MP3 DSC RF Tags Wireless Equipments Portable Equipments fp6733 G: Green TR: Tape/Real Package Type S6: SOT-23-6 S9: TSOT-23-6 2 FP6733fitipower integrated technology lnc. Typical Application Circuit CEEXTFP6733 GNDLXVDDFBCIN10 ~10 HCOUTVOUT10 FR1R2D11N5819 Option Figure 2. Typical Application Circuit of fp6733 Functional Pin Description Pin Name Pin Function CE IC chip enable EXT External switch transistor driver output GND Ground LX Internal switch MOS output VDD IC internal power supply FB Feedback input pin.

3 Internal reference voltage for error amplifier is 3 FP6733fitipower integrated technology lnc. Block Diagram Figure 3. Block Diagram of fp6733 Absolute Maximum Ratings LX to GND------------------------------------- ---------------------------------------- ------------------------ +6V All Other Pins to GND------------------------------------- ---------------------------------------- ---------- +6V Maximum Junction Temperature----------------------------- ---------------------------------------- ---- +150 C Power Dissipation @TA=25 C, SOT-23-6,TSOT-23-6 (PD) --------------------------------------- + Package Thermal Resistance, SOT-23-6,TSOT-26-6 ( JA)------------------------------------- -- +250 C/W Storage Temperature Range (TSTG)---------------------------------- ------------------------------------ -65 C to +150 C Lead Temperature (Soldering, 10sec.) (TLEAD)--------------------------------- ---------------------- +260 C Note1 Stresses beyond those listed under Absolute Maximum Ratings" may cause permanent damage to the device.

4 Recommended Operating Conditions Operating Voltage (VDD)----------------------------------- ---------------------------------------- -------- + to + Operating Temperature Range (TOPR)---------------------------------- -------------------------------- -40 C to +85 C 4 FP6733fitipower integrated technology lnc. Electrical Characteristics (TA=25 C, unless otherwise specified.) Parameter Symbol Test Conditions Min Typ MaxUnitsOperation Voltage VDD Normal Operation 2 V Start-Up Voltage VSTART VIN : 0 1V, IOUT=1mA No-Load Input Current INO_LOAD VIN= , VOUT= 75 A Continuous Switching CurrentISWITCH VDD= , VFB=0V mA No Switch Current IQ VIN=6V 17 25 A Shutdown Current ISD VDD= , CE pin=0V A Feedback Reference Voltage VFB Close loop.

5 VDD= EXT ON Resistance to VDD VDD= 5 EXT ON Resistance to GND VDD= 5 LX ON Resistance (Note2) RDS-ON VDD= Max. Duty Ratio DUTY VDD= 85 95 % Oscillator Frequency fOSC VDD= 450 550 650 kHz LX Leakage Current ILXL VLX=6V A Line Regulation VLINE VIN= ~ , IL=50mA 3 10 mV/VLoad Regulation VLOAD VIN=.

6 IL=1~100mA mV/mASwitch Current Limit (Note2) ILIMIT VDD= 1 A CE High Voltage VCEH VDD= , switch ON V CE Low Voltage VCEL VDD= , switch OFF V CE High Current ICEH VDD = , VCE=VDD A CE Low Current ICEL VDD = , VCE=0V A Efficiency (Note2) 85 % TSD 145 C Thermal Shutdown Threshold (Note2) TSD Hysteresis 30 C Note2: Guarantee by design.

7 5 FP6733fitipower integrated technology lnc. Typical Performance Curves Pin Trip Level(V)VDD(V) 12345624681012141618 EXT NMOS Resistance(ohm)VDD(V) Figure 4. Operation Voltage vs. En Pin Trip Level Figure 5. Operation Voltage vs. EXT NMOS Resistance Max Duty(%)VDD(V) LX On Resistance(ohm)VDD(V) Figure 6. Operation Voltage vs. Max Duty Figure 7. Operation Voltage vs. LX On Resistance Current (uA)Input Voltage (V) 1234560100200300400500600 ISW(uA)VDD(V)Figure 8. Input Voltage vs. Input Current Figure 9. Operation Voltage vs. Switch Current 6 FP6733fitipower integrated technology lnc. Typical Performance Curves (Continued) (uA)VDD(V) 123456300350400450500550600 Frequency (KHz) VDD (V) Figure 10. Operation Voltage vs. Quiescent Current Figure 11. Operation Voltage vs. Frequency -40-20 0 20406080300400500600700 Frequency (KHz)Temperture. (OC) -40-20 0 204060801012141618202224 Quiescent Current (uA)Temperture. (OC) Figure 12. Temperature vs.

8 Frequency Figure 13. Temperature vs. Quiescent Current -40-20 0 Switch current (mA)Temperture. (OC) 0 FeedBack Voltage (V)Temperture. (OC) Figure 14. Temperature vs. Switch current Figure 15. Temperature vs. Feedback Voltage 7 FP6733fitipower integrated technology lnc. Typical Performance Curves (Continued) -100010020030040050060070080065707580859 0 VIN= (%)Output Current (mA)VIN= 0200400600800100012005060708090 VIN= Efficiency (%)Output current (mA)VIN= 16. Efficiency (VOUT= ) Figure 17. Efficiency (VOUT= ) Output Voltage (V)Output Current (mA)VIN= Output Voltage (V)Output current (mA)VIN= 18. Load Regulation (VOUT= ) Figure 19. Load Regulation (VOUT= ) 8 FP6733fitipower integrated technology lnc. Application Information Operation The fp6733 is designed in a current mode PFM/PWM scheme which features an automatic switch PFM/PWM mode to maintain the highest efficiency and extend battery life. The quiescent current is less than 25uA at no switching status.

9 The control loop is internally compensated reducing the amount of external components. Chip Enable The fp6733 features a chip enable input pin that allows on/off control of the regulator. When CE=Low, shutdown of the chip occurs and at that time almost no quiescent current (<1uA) flows. The chip enable input is TTL/CMOS compatible. Connect CE to battery for normal operation. Current Limit Protection The fp6733 provides cycle-by-cycle over-current protection. Current limit is accomplished by sensing voltage drop across the drain to source of power switch. If the current sense amplifier output voltage is larger than current-limited threshold level (Typ. ), it will be immediately turned off power MOS. Thermal Protection Thermal protection limits total power dissipation in the fp6733 . When the junction temperature exceeds Tj = 145 C, the thermal sensor signals the shutdown logic and turns off most of the internal circuitry.

10 The thermal sensor turns internal circuitry on again after the IC s junction temperature drops by 30 C. Adjustable Output Voltage The output voltage of fp6733 ranges from to which is set by the external feedback resistor. It can be calculated as: )2R1R1( + = Inductor Selection A to 10uH is recommended for general used. The value of inductor depends on the operating frequency. Higher frequency allows smaller inductor and capacitor but increase internal switching loss. Two inductor parameters should be considered, current rating and DCR. The DCR of inductor affects the efficiency of the Converter . The inductor with lowest DCR is chosen for highest efficiency. The inductor value can be calculated as: OUTLINOUTINV*I*f)VV(VL = IL: inductor ripple current, usually set 20% x IL, which defined as: )VV(f*L)VV(IOUTININOUTL = The inductor should be rated for the maximum output current (IO(MAX)) plus the inductor ripple current ( IL) to avoid saturation.