RT9917 7 Channel DC/DC Converters General Description Features The RT9917 is a complete power-supply solution for digital still cameras and other hand-held devices. z z z It integrates : z CH1 : Boost DC-DC converter with load disconnect controller (SW1). z CH2 : Selectable Boost/Buck DC-DC converter z CH3 : Step-down DC-DC converter with internal compensation. CH4 : Step-down DC-DC converter with internal compensation. CH5 : DC/DC converter with HV NMOS, internal compensation and load disconnect (SW5) for CCD positive supply. z z z z 1 Channel Boost/Buck Selectable by SEL Pin 2 Selectable On/Off Sequence Set by SEQ Pin 4 Channels with Internal Compensation Provide Charge Pump Voltage to Enhance NMOS Gate Driving Capability for Alkaline Battery Input All Power Switches Integrated Syn Step-Down DC/DC Converter ` Up to 95% Efficiency ` 100% (MAX) Duty Cycle Syn Step-Up DC/DC Converter ` Adjustable Output Voltage ` Up to 95% Efficiency Open LED Protection Transformerless Inverting Converter for CCD Fixed 1MHz Switching Frequency Compact 40-Lead WQFN Package RoHS Compliant and 100% Lead (Pb)-Free CH6 : DC/DC converter with HV PMOS for CCD negative supply. z CH7 : WLED driver with HV NMOS, internal compensation and allow for PWM dimming. Applications z z SW1 : Load disconnect controller for CH1. z SW5 : Load disconnect switch for CH5. z Ordering Information Digital Still Camera PDA Portable Device Pin Configurations (TOP VIEW) Package Type QW : WQFN-40L 5x5 (W-Type) Lead Plating System P : Pb Free G : Green (Halogen Free and Pb Free) Note : Richtek 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. LX1 EN134 COMP1 FB1 OK134 VOUT1 FB2 COMP2 EN2 LX2 RT9917 40 39 38 37 36 35 34 33 32 31 PVDD1 LX6 PVDD6 CP CN CPO FB6 FB4 COMP6 LX4 1 30 2 29 3 28 4 27 5 6 26 GND 25 7 24 8 23 41 9 22 21 10 PVDD2 VDDM CFB7 GND LX7 LX5 VOUT7 FB3 EN7 LX3 PVDD4 EN5 SW5O SW5I FB5 VREF SEL SEQ EN6 PVDD3 11 12 13 14 15 16 17 18 19 20 WQFN-40L 5x5 DS9917-03 April 2011 www.richtek.com 1 RT9917 Typical Application Circuit For Li-ion : CH2 3.3V is from VOUT of CH1 VBAT C24 10uF L1 2.2uH VBAT 1uF 40 LX1 LX5 25 1 PVDD1 5V C1 10uF x 2 R1 37 150k C16 R15 560pF 39k R14 88.7k 5V C3 10uF 3.3V C17 10uF L4 4.7uH R16 470k C18 10pF R17 150k C19 R18 2.2nF 15k 31 LX2 C20 10uF L2 4.7uH 2.5V C4 22pF C5 10uF R3 768k RT9917 34 33 FB2 COMP2 23 C9 1nF R8 75k LX6 2 27 FB6 7 R11 C13 10.5k 0.1uF VREF 16 COMP6 PVDD6 R12 75k 9 C11 47pF 3 C26 1uF FB3 L6 10uH C14 1nF VBAT C27 1uF 11 VBAT L3 4.7uH C7 10uF R5 470k R6 374k -8V C12 4.7uF/16V R10 68k R4 360k C21 1.8V 10uF C6 33pF R7 887k L7 10uH PVDD3 21 LX3 C24 10uF/25V FB5 15 GND 20 VBAT SW5O 13 SW5I 14 FB1 38 COMP1 36 OK134 35 VOUT1 30 PVDD2 16V C8 10uF/25V C15 4.7pF R13 470k C25 1uF L5 10uH 29 VDDM 10 LX4 ON OFF Dimming LX7 26 D1 VOUT7 24 D2 D3 8 Power On PVDD4 39 32 12 19 22 FB4 EN134 EN2 EN5 EN6 EN7 VBAT 28 CFB7 4 CP CN 5 CPO 6 18 SEQ 17 SEL C10 1uF/16V D4 R9 10 VBAT Timing Diagram Power On Sequence : CH1 Boost 5V → CH3 Buck 2.5V → CH4 Buck 1.8V → CH2 Buck 3.3V Power Off Sequence : CH2 Buck 3.3V → CH4 Buck 1.8V → CH3 Buck 2.5V → CH1 Boost 5V VDDM EN134, EN2 CH1 VOUT 5V CH3 VOUT 2.5V CH4 VOUT 1.8V CH2 VOUT 3.3V www.richtek.com 2 User define 3.5ms 3.5ms 3.5ms 3.5ms IC shutdown Wait until FB3 < 0.1V Wait until FB4 < 0.1V Wait until FB2 < 0.1V DS9917-03 April 2011 RT9917 For Li-ion : CH2 3.3V is from VBAT VBAT C24 10uF VBAT 1uF L1 2.2uH 40 LX1 C25 1uF L5 10uH 29 VDDM LX5 25 16V 1 PVDD1 5V C1 10uF x 2 R1 150k C15 4.7pF R13 470k VBAT C3 10uF 3.3V C17 10uF L4 4.7uH R16 470k C18 10pF R17 150k C19 R18 2.2nF 15k FB1 38 COMP1 36 OK134 35 VOUT1 30 PVDD2 31 LX2 VBAT L2 4.7uH 2.5V C4 22pF C5 10uF R3 768k RT9917 34 33 FB2 COMP2 23 11 C21 1.8V 10uF C6 33pF L3 4.7uH C7 10uF R5 470k R6 374k ON OFF Dimming R8 75k 27 R11 C13 10.5k 0.1uF VREF 16 COMP6 -8V C12 4.7uF/16V R10 68k FB6 7 PVDD6 R12 75k 9 C11 47pF C14 1nF 3 VBAT C26 L6 1uF 10uH FB3 VBAT C27 1uF PVDD4 10 LX4 LX7 26 D1 VOUT7 24 D2 D3 8 Power On R7 887k LX6 2 R4 360k VBAT C9 1nF L7 10uH PVDD3 21 LX3 C24 10uF/25V FB5 15 GND 20 C20 10uF SW5O 13 SW5I 14 37 C16 R15 560pF 39k R14 88.7k C8 10uF/25V 39 32 12 19 22 FB4 EN134 EN2 EN5 EN6 EN7 28 CFB7 4 CP CN 5 6 CPO 18 SEQ 17 SEL C10 1uF/16V D4 R9 10 VBAT Timing Diagram Power On Sequence : CH1 Boost 5V → CH3 Buck 2.5V → CH4 Buck 1.8V → CH2 Buck 3.3V Power Off Sequence : CH2 Buck 3.3V → CH4 Buck 1.8V → CH3 Buck 2.5V → CH1 Boost 5V VDDM EN134, EN2 CH1 VOUT 5V CH3 VOUT 2.5V CH4 VOUT 1.8V CH2 VOUT 3.3V DS9917-03 April 2011 User define 3.5ms 3.5ms 3.5ms 3.5ms IC shutdown Wait until FB3 < 0.1V Wait until FB4 < 0.1V Wait until FB2 < 0.1V www.richtek.com 3 RT9917 For 2AA VBAT C24 10uF L1 2.2uH 3.3V VOUT 3.3V 1uF 40 LX1 AO3415 C1 10uF 1 R1 1M Q1 R13 470k C17 4.7pF R14 150k C18 R15 560pF 39k 37 L4 2.2uH VBAT 5V C19 10uF VBAT R16 470k C3 10uFx2 33 L2 4.7uH 2.5V C5 10uF R3 768k 25 RT9917 FB2 COMP2 PVDD3 C23 10uF L3 4.7uH 1.8V C7 10uF 27 R5 470k C6 33pF -8V C12 4.7uF/16V R10 68k R11 C13 10.5k 0.1uF VREF 16 PVDD6 10 LX4 R8 75k FB6 7 23 PVDD4 R7 887k LX6 2 R12 75k 9 C14 1nF C11 47pF 3 VBAT C26 L6 1uF 10uH R4 360k 3.3V C9 1nF L7 10uH COMP6 FB3 C24 10uF/25V FB5 15 21 LX3 11 16V C8 10uF/25V SW5O 13 SW5I 14 FB1 31 LX2 30 PVDD2 20 3.3V C4 22pF LX5 GND C21 560pF R18 39k C25 1uF L5 10uH PVDD1 38 COMP1 36 OK134 35 VOUT1 34 R17 88.7k C22 10uF 29 VDDM VBAT C27 1uF LX7 26 D1 VOUT7 24 D2 D3 8 R6 374k Power On ON OFF 39 32 12 19 22 Dimming FB4 EN134 EN2 EN5 EN6 EN7 28 CFB7 4 CP CN 5 CPO 6 18 SEQ 17 SEL C10 1uF/16V D4 R9 10 C15 0.1uF VBAT C16 1uF Note : A schottky diode connect from LX1 to PVDD1 is required for low-voltage start up. Timing Diagram Power On Sequence : CH1 Boost 3.3V→ CH3 Buck 2.5V → CH4 Buck 1.8V → (CH2 Boost 5V and SW1 3.3V) Power Off Sequence : (CH2 Boost 5V and SW1 3.3V)→ CH4 Buck 1.8V → CH3 Buck 2.5V → CH1 Boost 3.3V VDDM EN134, EN2 CH1 VOUT 3.3V CH3 VOUT 2.5V CH4 VOUT 1.8V VOUT1 3.3V CH2 VOUT 5V www.richtek.com 4 User define 3.5ms 3.5ms 3.5ms 3.5ms 3.5ms IC shutdown Wait until FB3 < 0.1V Wait until FB4 < 0.1V Wait until VOUT1 < 0.4V Depends on loading DS9917-03 April 2011 RT9917 Channel CH3 Formula VOUT = (1+R3/R4) x 0.8 VOUT (V) 2.5 1.8 1.3 1.2 1.0 L(uH) 4.7 4.7 4.7 4.7 4.7 R3(kΩ) 768 470 237 187 23.2 R4(kΩ) 360 374 374 374 93.1 C4(pF) 22 33 68 82 47 COUT (uF) 10 10 10 10 10 Channel CH4 Formula VOUT = (1+R5/R6) x 0.8 VOUT (V) 2.5 1.8 1.3 1.2 1.0 L(uH) 4.7 4.7 4.7 4.7 4.7 R5(kΩ) 768 470 237 187 23.2 R6(kΩ) 360 374 374 374 93.1 C6(pF) 22 33 68 82 47 COUT (uF) 10 10 10 10 10 Channel CH5 Formula VOUT = (1+R7/R8) x 1.25 VOUT (V) 12 13 15 15.5 16 L(uH) 10 10 10 10 10 R7(kΩ) 820 820 1000 820 886 R8(kΩ) 95.3 86.6 90.9 71.5 75 C9(pF) 1000 1000 1000 1000 1000 COUT (uF) 10/16V 10/16V 10/25V 10/25V 10/25V Channel CH6 Formula VOUT = (R10/R11)*(-1.25) * R10+R11 <90k VOUT (V) -6 -6.3 -7 -7.5 -8 L(uH) 10 10 10 10 10 R10(kΩ) 57.6 69.8 63.4 68 68 R11(kΩ) 12 13.7 11.3 11.3 10.5 COUT (uF) 10/16V 10/16V 4.7/16V 4.7/16V 4.7/16V R12(kΩ) 47 47 75 75 75 C11(pF) 47 47 47 47 47 C14(pF) 1000 1000 1000 1000 1000 DS9917-03 April 2011 www.richtek.com 5 RT9917 Functional Pin Description Pin No. Pin Name Pin Function 1 PVDD1 Power Input Pin for CH1. 2 LX6 Switch Node of CH6. High impedance in shutdown. 3 PVDD6 Power Input Pin for CH6. 4 CP Charge Pump External Driver Pin. 5 CN Charge Pump External Driver Pin. 6 CPO Output Pin for Charge Pump. 7 8 FB6 FB4 Feedback Input Pin for CH6. High impedance in shutdown. Feedback Input Pin for CH4. High impedance in shutdown. 9 COMP6 Compensation Pin for CH6. Pull to GND in shutdown. 10 LX4 Switch Node for CH4. High impedance in shutdown. 11 PVDD4 Power Input Pin for CH4. 12 EN5 Enable Pin for CH5. 13 SW5O Output Pin for CH5 Load Disconnect. 14 15 16 17 SW5I FB5 VREF SEL 18 SEQ 19 EN6 Input Pin for CH5 Load Disconnect. Feedback Input Pin for CH5. High impedance in shutdown. 1.25V Reference Output Pin. CH2 Boost/Buck Select Pin. Logic state can’t be changed during operation. CH1, CH3, CH4 Power On/Off Sequence Setting Pin. Logic state can’t be changed during operation. Enable Pin for CH6. 20 PVDD3 Power Input Pin for CH3 21 LX3 Switch Node for CH3. High impedance in shutdown. 22 EN7 Enable Pin for CH7. 23 FB3 Feedback Input Pin for CH3. High impedance in shutdown. 24 VOUT7 Sense Pin for CH7 Output Voltage. 25 LX5 Switch Node for CH5. High impedance in shutdown. 26 LX7 27, GND 41 (Exposed Pad) 28 CFB7 29 VDDM 30 31 32 33 34 35 36 37 38 39 40 PVDD2 LX2 EN2 COMP2 FB2 VOUT1 OK134 FB1 COMP1 EN134 LX1 www.richtek.com 6 Switch Node for CH7. High impedance in shutdown. Analog GND Pin. The exposed pad must be soldered to a large PCB and connected to GND for maximum thermal dissipation. Feedback Input Pin for CH7. IC analog Input Power Pin. This voltage is also used to drive power NMOS gate of CH5 and CH7. Power Input Pin for CH2. Switch Node for CH2. High impedance in shutdown. Enable Pin for CH2 Compensation Pin for CH2 Feedback Input Pin for CH2. High impedance in shutdown. Sense Pin for CH1 Output Voltage. High impedance in shutdown. External Switch Control Pin. High impedance in shutdown. Feedback Input Pin for CH1. High impedance in shutdown. Compensation Pin for CH1. Pull to GND in shutdown. Enable Pin for CH1, CH3, CH4, SW 1. Switch Node for CH1. High impedance in shutdown. DS9917-03 April 2011 RT9917 Function Block Diagram VDDM PVDD1 LX5 CH5 C-Mode Step-Up PWM SW5I CH1 C-Mode Step-Up LX1 SW5O FB5 + COMP1 FB1 - 1.25V REF + 0.8V REF PVDD6 PVDD2 CH6 C-Mode Inverting CH2 C-Mode Step-Up or Step-Down LX6 COMP6 FB6 LX2 + - COMP2 FB2 - LX7 + CH7 C-Mode Step-Up PWM VOUT7 EN7 CFB7 0.8V REF PVDD3 - CH3 C-Mode Step-Down + 0.25V REF Enable Mode Sequence SEQ SEL LX3 FB3 + EN134 EN2 EN5 EN6 CP CN CPO OK134 0.8V REF PVDD4 Charge Pump SW1 Controller CH4 C-Mode Step-Down LX4 REF FB4 + + - VOUT1 VREF 1.25V REF Oscillator Soft Start Thermal Protect 0.8V REF GND Timing Diagram CH5 and CH6 Timing Diagram EN5 max 18ms SW5I Depends on loading SW5O (to CCD +) Depends on loading EN6 CH6 VOUT DS9917-03 April 2011 max 18ms Depends on loading www.richtek.com 7 RT9917 Absolute Maximum Ratings z z z z z z z z z (Note 1) Supply Voltage, VDDM ------------------------------------------------------------------------------- 0.3V to 7V Power Input PVDD1, PVDD2, PVDD3, PVDD4, PVDD6 ------------------------------------ −0.3V to 7V Switch node : LX1, LX2, LX3, LX4 ----------------------------------------------------------------------------------- −0.3V to 7V LX5, LX7, SW5I, SW5O, VOUT7 ----------------------------------------------------------------- −0.3V to 21V LX6 ------------------------------------------------------------------------------------------------------- (PVDD6 − 14V) to (PVDD6 + 0.3V) The Other Pins ---------------------------------------------------------------------------------------- −0.3V to 7V Power Dissipation, PD @ TA = 25°C WQFN 40L 5x5 ---------------------------------------------------------------------------------------- 2.778W Package Thermal Resistance (Note 2) WQFN 40L 5x5, θJA ---------------------------------------------------------------------------------- 36°C/W WQFN 40L 5x5, θJC ---------------------------------------------------------------------------------- 7°C/W Junction Temperature -------------------------------------------------------------------------------- 150°C Lead Temperature (Soldering, 10 sec.) ---------------------------------------------------------- 260°C Storage Temperature Range ----------------------------------------------------------------------- −65°C to 150°C ESD Susceptibility (Note 3) HBM (Human Body Mode) ------------------------------------------------------------------------- 2kV MM (Machine Mode) --------------------------------------------------------------------------------- 200V Recommended Operating Conditions z z z z (Note 4) Supply Voltage, VDDM ------------------------------------------------------------------------------- 2.7V to 5.5V EN7 Dimming Control Frequency Range for CH7 --------------------------------------------- 1kHz to 100kHz (avoid 2k to 20kHz for audio noise) Junction Temperature Range ----------------------------------------------------------------------- −40°C to 125°C Ambient Temperature Range ----------------------------------------------------------------------- −40°C to 85°C Electrical Characteristics (VDDM = 3.3V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Condition Min Typ Max Units -- -- 1.6 V 5.6 6 6.5 V -- -- 0.6 V -- 1 10 uA Supply Voltage VDDM Minimum Startup Voltage V ST VDDM Over Voltage Protection VDDM Over Voltage Protection Hysteresis Supply Current Shutdown Supply Current into VDDM CH1 (Syn-Boost) + SW1 : Supply Current into VDDM CH2 (Syn-Boost or Syn-Buck) : Supply Current into VDDM CH3 (Syn-Buck) : Supply Current into VDDM I OFF EN134 = EN2 = EN5 = EN6 = EN7 = 0V I Q1 Non Switching, EN134 = 3.3V -- -- 800 uA I Q2 Non Switching, EN2 = 3.3V -- -- 800 uA I Q3 Non Switching, EN134 = 3.3V -- -- 800 uA To be continued www.richtek.com 8 DS9917-03 April 2011 RT9917 Parameter CH4 (Syn-Buck) : Supply Current into VDDM CH5 (Asyn-Boost) + SW5 : Supply Current into VDDM CH6 (Inverting) + Charge pump Supply Current into VDDM CH7 (WLED): Supply Current into VDDM Symbol IQ4 IQ5 IQ6 IQ7 Test Condition Non Switching, EN134 = 3.3V Non Switching, EN5 = 3.3V Non Switching, EN6 = 3.3V PVDD6 = 3.3V Non Switching, EN7 = 3.3V Min Typ Max Units -- -- 800 uA -- -- 800 uA -- -- 800 uA -- -- 800 uA 900 1000 1100 kHz Oscillator CH1,2,3,4,5,6,7 Operating Frequency fOSC CH1 Maximum Duty Cycle (Boost) VFB1 = 0.7V 80 83 86 % CH2 Maximum Duty Cycle (Boost) VFB2 = 0.7V 80 83 86 % CH2 Maximum Duty Cycle (Buck) VFB2 = 0.7V -- -- 100 % CH3 Maximum Duty Cycle (Buck) VFB3 = 0.7V -- -- 100 % CH4 Maximum Duty Cycle (Buck) VFB4 = 0.7V -- -- 100 % CH5 Maximum Duty Cycle (Boost) VFB5 = 1.15V 91 94 97 % CH6 Maximum Duty Cycle (Inverting) VFB6 = 0.1V 91 94 97 % CH7 Maximum Duty Cycle (WLED) CFB7 = 0.15V 91 94 97 % 0.788 0.8 0.812 V Feedback Regulation Voltage @ FB5 1.237 1.25 1.263 V Feedback Regulation Voltage @ FB6 -15 0 15 mV 0.237 0.25 0.263 V -- 140 -- uA 1.237 1.25 1.263 V 0μA < IREF < 200μA -- -- 10 mV P-MOSFET, PVDD1 = 3.3V -- 150 -- mΩ N-MOSFET, PVDD1 = 3.3V -- 150 -- mΩ N-MOSFET, PVDD1 = 3.3V -- 3 -- A P-MOSFET, PVDD2 = 3.3V -- 150 -- mΩ N-MOSFET, PVDD2 = 3.3V -- 150 -- mΩ CH2 Current Limitation (Buck) P-MOSFET, PVDD2 = 3.3V -- 1.5 -- A CH2 Current Limitation (Boost) N-MOSFET, PVDD2 = 3.3V -- 3 -- A P-MOSFET, PVDD3 = 3.3V -- 200 -- mΩ N-MOSFET, PVDD3 = 3.3V -- 200 -- mΩ P-MOSFET, PVDD3 = 3.3V -- 1.5 -- A Feedback Regulation Voltage Feedback Regulation Voltage @ FB1, FB2, FB3, FB4 Feedback Regulation Voltage @ CFB7 OK134 Sink Current OK134 = 1V Reference VREF Output Voltage V REF VREF Load Regulation Power Switch CH1 On Resistance of MOSFET RDS(ON) CH1 Current Limitation (Boost) CH2 On Resistance of MOSFET CH3 On Resistance of MOSFET CH3 Current Limitation (Buck) RDS(ON) R DS(ON) To be continued DS9917-03 April 2011 www.richtek.com 9 RT9917 Parameter Test Condition Min Typ Max Units P-MOSFET, PVDD4 = 3.3V -- 200 -- mΩ N-MOSFET, PVDD4 = 3.3V -- 200 -- mΩ CH4 Current Limitation (Buck) P-MOSFET, PVDD4 = 3.3V -- 1.5 -- A CH5 Load Disconnect MOSFET P-MOSFET, SW5I = 3.3V -- 0.5 -- Ω CH5 On Resistance of MOSFET N-MOSFET, VDDM = 3.3V -- 0.5 -- Ω CH5 Current Limitation N-MOSFET, VDDM = 3.3V -- 1.5 -- A CH6 On Resistance of MOSFET P-MOSFET, PVDD6 = 3.3V -- 1 -- Ω CH6 Current Limitation P-MOSFET, PVDD6 = 3.3V -- 1.5 -- A CH7 On Resistance of MOSFET N-MOSFET, VDDM = 3.3V -- 0.5 -- Ω CH7 Current Limitation N-MOSFET, VDDM = 3.3V -- 0.8 -- A Over Voltage Protection of PVDD1 -- 6 -- V Over Voltage Protection of PVDD2 -- 6 -- V Under Voltage Protection of VOUT1 -- 1.75 -- V Over Voltage Protection of SW5I -- 19 -- V CH4 On Resistance of MOSFET Symbol R DS(ON) Protection Over Voltage Protection of VOUT7 -- 19 -- V CH5 Load Disconnect UVP of SW5O -- 0.4 -- V -- 0.8 1.3 V 0.4 0.8 -- V -- 2 6 uA SEQ SEL Input High Level Threshold 1.3 -- -- V SEQ SEL Input Low Level Threshold -- -- 0.4 V Control EN134, EN2, EN5, EN6, EN7 Input High Level Threshold EN134, EN2, EN5, EN6, EN7 Input Low Level Threshold EN134, EN2, EN5, EN6, EN7 Sink Current SEQ SEL Sink Current EN134 or EN2 or EN5 or EN6 or EN7 = 3.3V -- 6 18 uA SEQ SEL Sink Current EN134 = EN2 = EN5 = EN6 = EN7 = 0V -- 0 0.1 uA 125 160 -- °C -- 20 -- °C Thermal Protection Thermal Shutdown TSD Thermal Shutdown Hysteresis ΔTSD 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. θJA is measured in the natural convection at TA = 25°C on a high effective four layers thermal conductivity test board of JEDEC 51-7 thermal measurement standard. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. www.richtek.com 10 DS9917-03 April 2011 RT9917 Typical Operating Characteristics CH2 Boost Efficiency vs. Output Current 100 90 90 80 80 70 VIN = VIN = VIN = VIN = VIN = VIN = 60 50 40 4.5V 4.2V 3.3V 2.5V 2.0V 1.8V Efficiency (%) Efficiency (%) CH1 Boost Efficiency vs. Output Current 100 30 20 VIN = VIN = VIN = VIN = VIN = VIN = 70 60 50 40 30 20 10 10 VOUT = 5V, L = 2.2μH, COUT = 10μFx2 0 10 100 VOUT = 3.3V, L = 2.2μH, COUT = 10μFx2 0 1000 10 100 Output Current (mA) 100 90 90 80 80 70 70 VIN = VIN = VIN = VIN = VIN = VIN = 50 40 30 20 Efficiency (%) Efficiency (%) CH4 Buck Efficiency vs. Output Current 100 60 3.0V 3.3V 3.6V 3.9V 4.2V 4.5V 10 10 60 VIN = VIN = VIN = VIN = VIN = VIN = 50 40 30 20 100 2.0V 2.5V 3.0V 3.3V 4.2V 4.5V 10 VOUT = 2.5V, L = 4.7μH, COUT = 10μF 0 1000 Output Current (mA) CH3 Buck Efficiency vs. Output Current VOUT = 1.8V, L = 4.7μH, COUT = 10μF 0 1000 10 100 Output Current (mA) 1000 Output Current (mA) CH6 Inverting Efficiency vs. Output Current CH5 Boost Efficiency vs. Output Current 100 100 90 90 80 80 VIN = VIN = VIN = VIN = VIN = VIN = 70 60 50 40 4.5V 4.2V 3.3V 2.5V 2.0V 1.8V Efficiency (%) Efficiency (%) 3.0V 2.7V 2.5V 2.2V 2.0V 1.8V 30 20 70 60 VIN = VIN = VIN = VIN = VIN = VIN = 50 40 30 20 10 VOUT = 15V, L = 10μH, COUT = 10μF 0 1 10 Output Current (mA) DS9917-03 April 2011 100 10 4.5V 4.2V 1.8V 2.0V 3.3V 2.5V VOUT = −8V, L = 10μH, COUT = 10μF 0 1 10 100 Output Current (mA) www.richtek.com 11 RT9917 CH7 Efficiency vs. Input Voltage CH1, CH2, CH3 and CH4 Power On 100 90 Efficiency (%) 80 VOUT_CH1 (2V/Div) 70 60 VOUT_CH2 (2V/Div) 50 40 VOUT_CH3 (2V/Div) 30 20 10 VOUT_CH4 (1V/Div) IOUT = 20mA, L = 10μH, COUT = 1μF SEQ = High, VIN = 3.6V 0 1.5 2 2.5 3 3.5 4 4.5 5 Time (2.5ms/Div) Input Voltage (V) CH1, CH2, CH3 and CH4 Power Off CH1, CH2, CH3 and CH4 Power On CH1 VOUT_CH1 (5V/Div) SW1_3.3V (2V/Div) VOUT_CH2 (2V/Div) SW1 CH2 VOUT_CH1 (1V/Div) VOUT_CH3 (2V/Div) VOUT_CH4 (2V/Div) SEQ = High, VIN = 3.6V VOUT_CH2 (2V/Div) VOUT_CH3 (2V/Div) VOUT_CH4 (1V/Div) CH3 CH4 SEQ = High, VIN = 3.0V Time (5ms/Div) Time (2.5ms/Div) CH1, CH2, CH3 and CH4 Power Off CH1 Output Voltage Ripple VIN = 3V, VOUT = 5V, IOUT = 300mA L = 2.2μH, COUT = 10μF x 2 CH1 VOUT_CH1 (2V/Div) SW1_3.3V (2V/Div) VOUT_CH2 (2V/Div) CH2 SW1 VOUT_CH3 (2V/Div) CH3 VOUT_CH4 (2V/Div) CH4 VOUT_ac (5mV/Div) SEQ = High, VIN = 3.0V Time (2.5ms/Div) www.richtek.com 12 LX1 (2V/Div) Time (500ns/Div) DS9917-03 April 2011 RT9917 CH2 Output Voltage Ripple CH3 Output Voltage Ripple VIN = 2.7V, VOUT = 3.3V, IOUT = 300mA L = 2.2μH, COUT = 10μF x 2 VIN = 4.2V, VOUT = 2.5V, IOUT = 300mA L = 4.7μH, COUT = 10μF LX2 (2V/Div) LX3 (2V/Div) VOUT_ac (5mV/Div) VOUT_ac (5mV/Div) Time (500ns/Div) Time (500ns/Div) CH4 Output Voltage Ripple CH5 Output Voltage Ripple VIN = 3.3V, VOUT = 1.8V, IOUT = 300mA L = 4.7μH, COUT = 10μF LX5 (5V/Div) LX4 (1V/Div) VOUT_ac (5mV/Div) VOUT_ac (2mV/Div) VIN = 1.8V, VOUT = 15V, IOUT = 30mA L = 10μH, COUT = 10μF Time (500ns/Div) Time (500ns/Div) CH6 Output Voltage Ripple CH7 Output Voltage Ripple LX6 (5V/Div) LX7 (5V/Div) VOUT_ac (5mV/Div) VOUT_ac (50mV/Div) VIN = 1.8V, VOUT = -8V, IOUT = 50mA L = 10μH, COUT = 10μF VIN = 1.8V, IOUT = 25mA (4 x WLED) L = 10μH, COUT = 1μF Time (500ns/Div) Time (2.5ms/Div) DS9917-03 April 2011 www.richtek.com 13 RT9917 CH2 Boost Output Voltage vs. Output Current 5.06 3.39 5.05 3.38 5.04 3.37 Output Voltage (V) Output Voltage (V) CH1 Boost Output Voltage vs. Output Current 5.03 5.02 5.01 5.00 4.99 3.36 3.35 3.34 3.33 3.32 3.31 4.98 4.97 3.30 VIN = 3.0V VIN = 2.5V 3.29 4.96 0 50 0 100 150 200 250 300 350 400 450 500 50 100 150 200 250 300 350 400 450 500 Output Current (mA) Output Current (mA) CH4 Buck Output Voltage vs. Output Current CH3 Buck Output Voltage vs. Output Current 2.57 1.84 2.56 1.83 Output Voltage (V) Output Voltage (V) 2.55 2.54 2.53 2.52 2.51 2.50 2.49 1.82 1.81 1.8 1.79 1.78 1.77 2.48 VIN = 3.3V VIN = 3.7V 2.47 0 1.76 0 50 100 150 200 250 300 350 400 450 500 550 600 50 100 150 200 250 300 350 400 450 500 550 600 Output Current (mA) Output Current (mA) CH6 Inverting Output Voltage vs. Output Current CH5 Boost Output Voltage vs. Output Current -8.03 15.20 -8.02 15.10 Output Voltage (V) Output Voltage (V) 15.15 15.05 15.00 14.95 14.90 -8.01 -8 -7.99 -7.98 14.85 VIN = 3.7V 14.80 0 10 20 30 40 50 60 70 Output Current (mA) www.richtek.com 14 80 90 100 VIN = 3.7V -7.97 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 Output Current (mA) DS9917-03 April 2011 RT9917 Application information The RT9917 includes the following seven DC/DC converter channels to build a multiple-output power-supply system. CH1 : Step-up synchronous current mode DC/DC converter with internal power MOSFETs. The output voltage could be load disconnected by a switch controller and an external PMOS. CH2 : Selectable step-up or step-down synchronous current mode DC/DC converter with internal power MOSFETs. CH3 : Step-down synchronous current mode DC/DC converter with internal power MOSFETs and internal compensation network. CH4 : Step-down synchronous current mode DC/DC converter with internal power MOSFETs and internal compensation network. CH5 : Step-up asynchronous current mode DC/DC converter with internal power MOSFET and internal compensation network. The output voltage could be load disconnected by an internal PMOS. CH6 : Inverting current mode DC/DC converter with internal power MOSFET. CH7 : Current mode WLED driver with internal power MOSFET and internal compensation network. Also provides open LED protection. SW1 : Load disconnect controller for CH1. SW5 : Load disconnect switch for CH5 All converters operate in PWM mode with 1MHz constant frequency under moderate to heavy loading. The RT9917 also provides two different on/off sequences by setting “SEQ” pin. CH1 : Step-Up Converter Step-up : The converter operates at fixed frequency PWM mode and continuous current mode (CCM) with internal MOSFET and synchronous rectifier for up to 95% efficiency. Add a SBD between LX1 and PVDD1 for 2AA battery application. DS9917-03 April 2011 CH2 : Selectable Step-Up or Step-Down Converter Step-up : The converter operates at fixed frequency PWM mode and continuous current mode (CCM) with internal MOSFET and synchronous rectifier for up to 95% efficiency. Step-down : The converter operates at fixed frequency PWM mode and continuous current mode (CCM) with internal MOSFET and synchronous rectifier for up to 95% efficiency. While the input voltage is close to the output voltage, the converter enters low dropout mode. The duty could be as long as 100% to extend battery life. CH3 : Step-Down DC/DC Converter The converter operates at fixed frequency PWM mode, CCM and integrated internal compensation. While the input voltage is close to the output voltage, the converter could enter low dropout mode with low output ripple. The duty could be as long as 100% to extend the battery life. CH4 : Step-Down DC/DC Converter The converter operates at fixed frequency PWM mode, CCM and integrated internal compensation. While the input voltage is close to the output voltage, the converter could enter low dropout mode with low output ripple. The duty could be as long as 100% to extend the battery life. CH5 : Step-Up DC/DC Converter It integrates asynchronous boost with an internal MOSFET, internal compensation and an external schottky diode to provide CCD positive power supply. The converter is inactive until the SW5 soft start procedure is finished. This feature provides load disconnect function and effectively limits the inrush current at start up. CH6 : INV DC/DC Controller This controller integrates an internal P-MOSFET and an external schottky diode to provide CCD negative power supply. The output voltage is set as VOUT = (R10/R11) x (-1.25) (R10, R11 refer to Typical Application Circuit). www.richtek.com 15 RT9917 CH7 : WLED Driver Mode and sequence setting It is an asynchronous DC/DC converter with an internal MOSFET, internal compensation and an external schottky diode to drive up to 4 WLED. This channel also features PWM dimming control from EN7 pin and open diode protection. The current through WLED is set as Please refer to “Electrical Characteristics” for level of logic high or low. Table 1. Mode setting I (mA) = [250mV/R(Ω)] x Duty (%) SEL CH2 High Boost Low Buck R : Current sense resistor from CFB7 to GND. For CH2, Mode setting is decided by “SEL” pin. The Duty : PWM dimming by EN7 pin. Dimming frequency range is from 1kHz to 100kHz but it is recommended to avoid 2kHz to 20kHz for audio noise. Hold EN7 low for more than 15ms will turn off CH7. CH2 of RT9917 features flexible boost or buck topology setting for either 1x Li-ion or 2 x AA application by one pin. Table 2. Sequence setting SEQ Power ON Sequence SW1 High CH1 -> CH3 -> CH4 -> (SW1 and CH2) SW1 is an open drain controller to drive an external PMOS Low CH3 -> CH4 -> CH1 -> (SW1 and CH2) SEQ Power OFF Sequence High (SW1 and CH2) -> CH4 -> CH3 -> CH1 Low (SW1 and CH2) -> CH1 -> CH4 -> CH3 and then functions as a load disconnect switch for CH1. This switch features soft start, Power On/Off Sequence and under voltage protection functions. OK134 is an open drain control pin. Once CH1, CH3 and CH4's soft start are completed, SW1 is on. The OK134 pin is slowly pulled low and controlled with soft start to suppress the inrush current. VOUT1 is used for SW1 soft start and under voltage protection. If SW1 is not used, connect a resistor to VOUT1 (Refer to Typical Application Circuit for Li-ion). SW5 SW5 is an internal switch enabled by EN5 and functions as a load disconnection for CH5. This switch features soft start, Powe On Sequence, over voltage (for SW5I) and under voltage (for SW5O) protection functions. Sequence setting is decided by “SEQ” pin.Please note that the logic state can not be changed during operation. SEQ = High The Power On Sequence is : ` While EN134 goes high, CH1 will be turned on to wait for the completion of CH1's soft start. ` After that, CH3 will be turned on to wait for the completion of CH3's soft start. Charge Pumps ` And then, CH4 will be turned on to wait for the completion of CH4's soft start. The charge pump function is enabled while battery type is alkaline battery. This channel provides pump voltage to ` Then, SW1 will be turned on and CH2 is allowed to be turned on by EN2 at any time. enhance MOS gate driving capability. This function is not necessary while battery is Li-ion type. ` Finally, SW1's soft start will be completed. Reference Voltage The RT9917 provides a precise 1.25V reference voltage with sourcing capability 100μA. Connect a 0.1μF ceramic capacitor from VREF pin to GND. Reference voltage is enabled by connecting EN6 to logic high. Furthermore, this reference voltage is internally pulled to GND in shutdown. www.richtek.com 16 The Power-Off Sequence is : ` At first, while EN134 goes low, (SW1 is showdown and internally pulled low, CH2 must be turned off by EN2) SW1 (note 1) and CH2 (note 2) will be shutdown. ` After that, CH4 will be turned off and internally pulled low to wait for the completion of CH4's shutdown. ` And then, CH3 will be turned off and internally pulled low to wait for CH3's shutdown completion. DS9917-03 April 2011 RT9917 ` Then, CH1 will be turned off and internally pulled low (note 3) to wait for CH1's shutdown completion. ` Finally, the whole IC will be shutdown (if EN5, EN6 and EN7 already go low). of CH1's soft start. ` Then, SW1 will be turned on and CH2 is allowed to be turned on by EN2 at any time. ` Finally, SW1's soft start will be completed. Note 1 : The SW1 is designed for CH1. The Power-Off Sequence is : Note 2 : If CH2 is configured as a Boost, then the CH2 will not be internally pulled low and the completion of shutdown will not be checked. ` At first, while EN134 goes low, (SW1 is showdown and internally pulled low, CH2 must be turned off by EN2) SW1 (note 1) and CH2 (note 2) will be shutdown. Note3 : CH1 is configured as a Boost, so the CH1 will not be internally pulled low and the completion of shutdown will not be checked. ` Then, CH1 will be turned off and internally pulled low (note 3) to wait for CH1's shutdown completion. SEQ = Low The Power On Sequence is : ` While EN134 goes high, CH3 will be turned on to wait for the completion of CH3's soft start. ` After that, CH4 will be be turned on to wait for the completion of CH4's soft start. ` After that, CH4 will be turned off and internally pulled low to wait for the completion of CH4's shutdown. ` And then, CH3 will be turned off and internally pulled low to wait for CH3's shutdown completion. ` Finally, the whole IC will be shutdown (if EN5, EN6 and EN7 already go low). ` And then, CH1 will be turned on to wait for the completion Protection VDDM CH1:Boost CH2:Boost Protection Threshold (typical) Protection methods type Refer to Electrical spec Over Voltage Disable all channels VDDM > 6V Protection (except CH7) Restart if VDDM < 5.6V (with hysteresis) Current Limit NMOS current> 3A NMOS off, PMOS on Automatic reset at next clock cycle PVDD1 OVP PVDD1 > 6V IC shutdown (except CH7) VDDM power reset Current Limit NMOS current> 3A NMOS off, PMOS on PVDD2 OVP PVDD2 > 6V IC shutdown (except CH7) VDDM power reset Reset m ethod Automatic reset at next clock cycle CH2:Buck OCP PMOS current > 1.5A IC shutdown (except CH7) VDDM power reset CH3:Buck OCP PMOS current > 1.5A IC shutdown (except CH7) VDDM power reset CH4:Buck OCP PMOS current > 1.5A IC shutdown (except CH7) VDDM power reset CH5: OCP NMOS current > 1.5A NMOS off CH6: OCP PMOS current > 1.5A IC shutdown (except CH7) VDDM power reset OCP NMOS current > 0.8A NMOS off Automatic reset at next clock cycle OVP VOUT7 > 19V Shutdown CH7 Reset by toggling EN7 CH7:WLED SW1 UVP OVP SW5 Thermal UVP Thermal shutdown DS9917-03 April 2011 Automatic reset at next clock cycle VOUT1 < 1.75V IC shutdown (except CH7) VDDM power reset after SW1 soft start end SW5I > 19V IC shutdown (except CH7) VDDM power reset SW5O < 0.4V IC shutdown (except CH7) VDDM power reset after SW5 soft start end All channels stop Temperature > 160°C Temperature < 140°C switching www.richtek.com 17 RT9917 Thermal Considerations Layout Consideration For continuous operation, do not exceed absolute maximum operation junction temperature. The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surroundings airflow and temperature difference between junction to ambient. The maximum power dissipation can be calculated by following formula : ` All the traces of the compensation components should be short to reduce the parasitic connection resistance and isolated from other noisy device traces. The ground traces must be connected to ground plane independently. PD(MAX) = ( TJ(MAX) - TA ) / θJA ` All the traces of the feedback components should be short to reduce the parasitic connection resistance and isolated from other noisy device traces. The ground traces must be connected to ground plane independently. Output sense trace must be kept away from the noisy device (inductor). Where T J(MAX) is the maximum operation junction temperature 125°C, TA is the ambient temperature and the θJA is the junction to ambient thermal resistance. For recommended operating conditions specification, 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 is layout dependent. For WQFN-40L 5x5 packages, the thermal resistance θJA is 36°C/W on the standard JEDEC 51-7 four layers thermal test board. The maximum power dissipation at TA = 25°C can be calculated by following formula : PD(MAX) = (125°C − 25°C) / (36°C/W) = 2.778W for WQFN-40L 5x5 packages The maximum power dissipation depends on operating ambient temperature for fixed T J(MAX) and thermal resistance θJA. For RT9917 package, the Figure 1 of derating curves allows the designer to see the effect of rising ambient temperature on the maximum power allowed. Maximum Power Dissipation (W) 3.6 Four Layers PCB 3.2 Compensative parts: R15, C16, R18, C19, R12, C11, C14. Feedback parts: R13, R14, C15 for CH1. R16, R17, C18 for CH2. R3, R4, C4 for CH3. R5, R6, C6 for CH4. R7, R8, C9 for CH5. R10, R11, C13for CH6. R9 for CH7. ` All the traces of connecting inductor must be as wide as possible. Inductor: L1, L2, L3, L4, L5, L6, L7. ` Output Capacitor should be placed close to Vout and connected to ground plane to reduce noise coupling. Output capacitor: C1, C5, C7, C8, C10, C12, C17 and C24. ` Input capacitor should be placed close to Vbat and connected to ground plane. Input capacitor: C2, C3, C20, C21, C26, C27 and C28. 2.8 ` The GND (Pin 27) and Exposed Pad should be connected to a strong ground plane for heat sinking and noise protection. 2.4 2.0 1.6 ` The EN7 pin is used for dimming control. Keep the FB3 trace away from the EN7. 1.2 0.8 0.4 0.0 0 15 30 45 60 75 90 105 120 135 Ambient Temperature (°C) Figure 1. Derating Curves for RT9917 Packages www.richtek.com 18 DS9917-03 April 2011 RT9917 LX should be connected to inductor by wide and short trace, keep sensitive components away from this trace. VOUT1 Place the feedback and compensation components as close as possible to the FB and COMP pin and keep away from noisy devices. VOUT2 GND C15 GND VBAT GND R16 C17 C18 R13 C16 C19 R1 R15 L1 C1 C6 R5 R6 C14 PVDD1 LX6 D2 PVDD6 CP R10 CN CPO R11 FB6 FB4 COMP6 R12 LX4 2 29 3 28 4 27 5 25 24 7 8 23 41 9 22 21 10 11 12 13 14 15 16 17 18 19 20 L3 C20 C21 GND 26 GND 6 C7 VOUT4 30 1 VBAT C11 D3 C3 C24 R8 C9 R7 PVDD2 VDDM CFB7 GND LX7 LX5 VOUT7 FB3 EN7 LX3 C25 R9 VBAT D2 D1 D3 L6 WLED+ VBAT C26 L5 C27 VBAT D1 C10 GND VOUT5 C8 R4 R3 C4 L2 GND C5 VOUT3 VBAT C13 D4 40 39 38 37 36 35 34 33 32 31 GND VOUT6 C12 WLED- LX1 EN134 COMP1 FB1 OK134 VOUT1 FB2 COMP2 EN2 LX2 C2 L7 L4 R17 PVDD4 EN5 SW5O SW5I FB5 VREF SEL SEQ EN6 PVDD3 Input/Output capacitors must be placed as close as possible to the Input/Output pins. R18 R14 GND GND VOUT5 Connect the Exposed Pad to a ground plane. Figure 2 DS9917-03 April 2011 www.richtek.com 19 RT9917 Outline Dimension D SEE DETAIL A D2 L 1 E E2 e b 1 1 2 2 DETAIL A Pin #1 ID and Tie Bar Mark Options A A3 A1 Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 0.700 0.800 0.028 0.031 A1 0.000 0.050 0.000 0.002 A3 0.175 0.250 0.007 0.010 b 0.150 0.250 0.006 0.010 D 4.950 5.050 0.195 0.199 D2 3.250 3.500 0.128 0.138 E 4.950 5.050 0.195 0.199 E2 3.250 3.500 0.128 0.138 e L 0.400 0.350 0.016 0.450 0.014 0.018 W-Type 40L QFN 5x5 Package 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: [email protected] 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 20 DS9917-03 April 2011