rt9911 Richtek Technology Corporation, rt9911 Datasheet

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... Channel DC/DC Converters General Description The RT9911 is a complete power-supply solution for digital still cameras and other hand-held devices. It integrates one selectable Boost/Buck DC-DC converter, one high- efficiency step-down DC-DC converter, one high-efficiency main step-up converter, one PWM converter for CCD positive voltage, one inverter for CCD negative voltage and one white LED driver for LCD backlight ...

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... Bottom pad is GND pad, can be short to pin 6 (GND). Please remove Q2 when use Async Boost and remove D5 when use Sync Boost. www.richtek.com 3.3V BAT 1. 4.7uH D9 11 PVDD1 C7 10 100pF LX1 7 FB1 9 RT9911 PGND1 R3 150k 29 PGND2 PVDD5 2 OK2 1 GND L2 4.7uH 30 LX2 C10 100pF 33 FB2 31 PVDD2 Bottom PAD 20 PVDD3 ...

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... D8 19 EXT6 C31 Q6 4.7uF 23 VFB6 22 CFB6 35 EN1 EN1 36 EN1 EN2 37 EN3 EN3 38 EN4 EN4 39 EN5 EN5 40 EN6 EN6 1M RT9911 CCD 12V 20mA R10 C25 2.2M 100pF 205k R11 CCD -8V R13 C28 40mA 1M 10uF R14 C29 125k 4.7uF R24 20k D1 R15 D2 300k D3 D4 ...

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... RT9911 Functional Pin Description Pin No. Pin Name Pin Function 1 GND Analog Ground Pin 2 OK2 External Switch Control. Frequency Setting Pin. Frequency 500kHz if RT pin not connected. 5 VDDM Device Input Power Pin 6 GND Analog Ground Pin 4 VREF 1.0V Reference Pin 7 FB1 Feedback Input Pin of CH1. ...

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... DS9911-04 August 2007 Internal State at I/O Shut Down OUT Pull Low OUT Pull Low IN -- Pull High OUT Pull Low IN High Impedance IN High Impedance 50uA Pull Low IN High Impedance RT9911 I/O Configuration PVDD5 EXT4 PVDD5 EXT6 PVDD3 DRP3 COMP6 0.2V + CFB6 - VFB6 1. PVDD3 DRN3 VDDM CS3 To be continued www ...

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... RT9911 Pin No. Pin Name Pin Function Feedback Compensation Pin of 27 COMP3 CH3 28 FB3 Feedback Input Pin of CH3. 29 PGND2 Power Ground Pin of CH2 30 LX2 Switch Node of CH2 31 PVDD2 Power Input Pin of CH2. Feedback Compensation Pin of 32 COMP2 CH2. 33 FB2 Feedback Input Pin of CH2. ...

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... PCB and connected to GND GND for maximum power Pad (41) dissipation. DS9911-04 August 2007 Internal State at I/O Shut Down IN Pull Low IN Pull Low IN Pull Low IN Pull Low -- -- -- RT9911 I/O Configuration VDDM EN3 2uA VDDM EN4 2uA VDDM EN5 2uA VDDM EN6 2uA www.richtek.com 7 ...

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... RT9911 Function Block Diagram EN4 EXT4 COMP4 FB4 EN5 PVDD5 EXT5 COMP5 FB5 VREF OK2 EN6 EXT6 VFB6 COMP6 CFB6 www.richtek.com 8 VDDM PVDD5 CH4 V-Mode Step-Up CH1 PWM C-Mode Step-Up or Step-Down - + 1.0V REF CH5 Inverter + - CH2 1.0V C-Mode REF Step-Down Switch Controller PVDD5 ...

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... VDDM Pin Voltage DDM EN1 = EN2 = EN3 = EN4 = EN5 OFF = EN6 = 3.3V, Non-Switching Q1 DDM 3.3V, Non-Switching Q2 DDM 3.3V, Non-Switching Q3 DDM 3.3V, Non-Switching Q4 DDM 3.3V, Non-Switching Q5 DDM 3.3V, Non-Switching Q6 DDM RT9911 + 0.3V) DD Min Typ Max Units -- -- 1.6 V 2.4 -- 5.5 V 5.9 6 430 350 350 uA -- ...

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... RT9911 Parameter Oscillator Operation Frequency CH1 Maximum Duty Cycle (Boost) CH1 Maximum Duty Cycle (Buck) CH2 Maximum Duty Cycle CH3 Maximum Duty Cycle CH4 Maximum Duty Cycle CH5 Maximum Duty Cycle CH6 Maximum Duty Cycle Feedback Regulation Voltage Feedback Regulation Voltage @ FB1, ...

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... DD5 DS(O N)N5 R P-MOSFET, PV DS(O N)P6 DD5 N-MOSFET DD5 DS(O N)N6 OK2 = 1V I CS3 I VFB 6 SELECT = 0V SELECT = 3.3V DDM V = 3.3V DDM V = 3.3V DDM I SELECT T SD Δ 25° low effective thermal conductivity test board of A RT9911 Min Typ Max = 0.3 0.4 0 ...

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... RT9911 Typical Operating Characteristics CH1 Boost Efficiency vs. Output Current 100 Ch1 Boost 3.3V OUT 0 10 Output Current (mA) CH1 Boost LX1 and Output Voltage Ripple V = 1.8V 3.3V OUT Time (1μs/Div) CH1 Boost Load Transient Response V = 3.0V 3.3V IN OUT Time (1ms/Div) www ...

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... Loading Current (mA) CH2 Buck Efficiency vs. Output Current 100 2. 3. 1.8V OUT 0 10 100 Output Current (mA) CH2 LX2 and Output Voltage Ripple V = 4.2V 2.5V OUT OUT Time (1μs/Div) RT9911 600 700 800 900 1000 = 400mA www.richtek.com 13 ...

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... RT9911 CH2 Load Transient Response V = 3.0V 2.5V IN OUT Time (1ms/Div) CH2 Load Transient Response V = 4.2V 2.5V IN OUT Time (1ms/Div) CH2 Buck Output Voltage vs. Output Current 3.370 3.360 3.350 3.340 3.330 3.320 3.310 3.300 3.290 3.280 V = 3.7V 3.3V IN OUT 3.270 0 100 200 300 400 500 600 700 800 900 100 Output Current (mA) www ...

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... CH3 Boost Efficiency vs. Output Current 100 OUT 0 10 100 Output Current (mA) CH3 LX3 and Output Voltage Ripple V = 1.8V 3.3V 400mA IN OUT OUT Time (1μs/Div) CH3 Load Transient Response V = 3.0V 3.3V IN OUT Time (1ms/Div) RT9911 3.8V = 3.2V = 2.5V = 2.0V = 1.5V 1000 www.richtek.com 15 ...

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... RT9911 CH3 Boost Output Voltage vs 2.5V 3.3V OUT 3.29 3.28 3.27 3.26 3.25 3.24 3.23 3.22 3.21 3.20 2.4 2.8 3.2 3.6 V Voltage (V) DDM CH3 Boost Output Voltage vs. Output Current 5.020 V = 3.7V OUT 5.015 5.010 5.005 5.000 4.995 4.990 4.985 4.980 4.975 0 0.1 0.2 0.3 0.4 Output Current (A) CH4 LX4 and Output Voltage Ripple V = 1.8V 12V OUT Time (1μ ...

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... CH4 Output Voltage vs. V 15. 2.5V, PVDD5 = 3.3V OUT 15.41 15.40 15.39 15.38 15.37 15.36 15.35 15.34 15.33 15.32 2.4 2.8 3.2 3 Voltage (V) DDM CH5 Inverting Efficiency vs. Output Current 100 1. 2. 2. Output Current (mA) CH5 Load Transient Response V = 1.8V -8V IN OUT Time (1ms/Div) RT9911 Voltage DDM = 30mA 4.4 4.8 5.2 5 -8V OUT 100 www.richtek.com 17 ...

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... RT9911 CH5 Output Voltage vs. V -8. 3.0V, PVDD5 = 3.3V -8.03 -8.04 -8.05 -8.06 -8.07 -8.08 -8.09 -8.10 -8.11 -8.12 2.4 2.8 3.2 3.6 V Voltage (V) DDM CH5 Output Voltage vs. Output Current -8.152 -8.151 -8.150 -8.149 -8.148 -8.147 -8.146 -8.145 -8.144 -8.143 V = 3.7V -8V IN OUT -8.142 0 -10 -20 -30 -40 Loading Current (mA) CH6 LX6 and Output Voltage Ripple V = 1.8V WLED, I ...

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... CH1 and CH2 Power Sequence Time (1ms/Div) Feedback Voltage vs. Temperature 1.04 1.00 0.96 0.92 0.88 0.84 V FB1 0.80 0.76 0.72 -40 - Temperature DS9911-04 August 2007 Start Up 2. FB4 FB6 , FB2 FB3 100 (°C) RT9911 CH4 and CH5 Power Sequence Start Up Time (2ms/Div) www.richtek.com = 2.5V 19 ...

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... PVDD5 source voltage of PMOS. See Figure 3(f) for detailed functional block. Reference Voltage RT9911 provides a precise 1V reference voltage with souring capability 100uA. Connect a 1uF ceramic capacitor from VREF pin to GND. Reference voltage is enabled by connecting EN5 to logic high. external MOSFETs and a synchronous rectifier, the ...

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... LX1 PGND1 PVDD3 OSC COMP4 DRP3 1.0V Logic Driver FB4 DRN3 PGND2 PVDD5 OSC COMP5 FB5 Logic Driver GND EXT6 GND Figure 3. Detailed Functional Block for each channel RT9911 Logic Driver + Current Sense Fault Slope Protection compensation Figure 3( Logic Driver ...

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... RT9911 VDDM (VS 3.3V) Note : Please refer to Figure 1 for application Information. Timing sequence should be controlled by EN pins. Calculation method: Td1 to Td6 are precise value. Tr1 to Tr6 are approximation. Units : T in second Farad Ohm C31 to C36 : Compensation capacitor of CH1 to CH6. T1d = 0.7V x C31 / 2uA (CH1 Boost) T1d = 0 ...

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... Soft Start With internal soft start mechanism, the soft start time of each channel is proportional to the compensation capacitor. Refer to the soft start waveform application. Protection RT9911 provides versatile protection functions. Protection type, threshold and protection methods are summarized in Table 1. Protection Threshold (typical) type ...

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... CH3 CS3 PWM DRN3 Figure 6. CH3 Current Limit Setting RT9911 Component Selection for Compensation : CH1 Sync-Boost (Select Pin = High Logic) : CH1 sync-boost converter employs current-mode control to simplify the control loop compensation. There is a RHPZ (Right Hand Plane Zero) appeared in the loop-gain ...

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... P R 23k C There is no RHPZ (Right >= f /π . The f HP OSC Transconductance (from FB to COMP 200us Current sense transresistance, R Feedback voltage 0.8V FB R1, the voltage divider resistor in between V FB. RT9911 − 6.3nF. μ 4.8pF , (cross over 0.3V/A CS and OUT www.richtek.com ...

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... RT9911 V , input voltage desired output voltage OUT I , maximum output load OUT(MAX operating frequency OSC L, inductance R , ESR (Equivalent Series Resistance ESR (ceramic output capacitor) T (%), Transient droop. DRP The results we will get for CH1 boost compensation are as follows: R2, the voltage divider resistor in between FB and ground. ...

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... Transconductance (from FB to COMP 200us. Internal voltage ramp to decide duty cycle, V OUT Feedback voltage, V COMP and C , output capacitance. This compensation is based = DS(ON OUT Figure 9 RT9911 = 1V ESR I OUT C OUT www.richtek.com 27 ...

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... RT9911 The input parameters for CH4 asyn-boost in DCM compensation are as follows : R1, the voltage divider resistor in between V FB input voltage desired output voltage OUT I , maximum output load OUT(MAX operating frequency OSC L, inductance C , output capacitance. This compensation is based OUT on ceramic output capacitor. ...

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... Transconductance (from FB to COMP 200us Internal voltage ramp to decide duty cycle, V Feedback voltage Reference voltage REF V OUT COMP 20k 4.7uF Figure 10 RT9911 to cancel another cdp OUT < 10pF ESR I OUT C OUT REF www.richtek.com 29 ...

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... RT9911 The input parameters for CH5 asyn-inverter in DCM compensation are as follows : R1, the voltage divider resistor in between V FB input voltage desired output voltage OUT I , maximum output load OUT(MAX operating frequency OSC L, inductance C , output capacitance. This compensation is based OUT on ceramic output capacitor. ...

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... The feedback netwok should be very close to the FB pin. The compensation network should be very close to the COMP pin and avoid through VIA. For CH3 current sense, CS should be close to the drain site of external NMOS. Keep high current path as short as possible. RT9911 of the double pole. OUT < ...

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... RT9911 Outline Dimension D A Symbol Richtek Technology Corporation Headquarter 5F, No. 20, Taiyuen Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Fax: (8863)5526611 www.richtek.com Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. ...