RT9624BZQW

DATASHEET SEARCH SITE | WWW.ALLDATASHEET.COM

Document overview

• Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
• PDF pages: 16

Technical content

Features

 Drive Two N-MOSFETs  Shoot Through Protection  Embedded Bootstrap Diode  Support High Switching Frequency  Fast Output Rising Time  Tri-State PWM Input for Output Shutdown  Small SOP-8, SOP-8 (Exposed Pad) and 8-Lead WDFN Packages  RoHS Compliant and Halogen Free

Applications

 Core Voltage Supplies for Desktop, Motherboard CPU  High Frequency Low Profile DC/DC Converters  High Current Low Voltage DC/DC Converters  Core Voltage Supplies for GFX Card General Description The RT9624B is a high frequency, synchronous rectified, single phase MOSFET driver designed for normal MOSFET driving applications and high performance CPU VR driving capabilities. The RT9624B can be supplied from 4.5V to 13.2V. The applicable power stage VIN range is from 5V to 24V. The IC also builds in an internal power switch to replace external bootstrap diode. The RT9624B can support switching frequency efficiently up to 500kHz. The IC has both the UGATE and LGATE driving circuits for synchronous rectified DC/DC converter applications. The shoot through protection mechanism is designed to prevent shoot through between high side and low side power MOSFETs. The RT9624B has tri-state PWM input with shutdown function, which can force driver to output low UGATE and LGATE signals. The RT9624B comes in a small footprint with 8-pin packages. The choice of package types includes SOP-8, SOP-8 (Exposed Pad) and WDFN-8L 3x3. VCC PWM GND BOOT UGATE PHASE LGATE RT9624B 12V PWM Controller + VOUT CBOOT R4 R5 VIN Simplified Application Circuit

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation.

Ordering Information

Note : Richtek products are :  RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020.  Suitable for use in SnPb or Pb-free soldering processes. (TOP VIEW) SOP-8 SOP-8 (Exposed Pad) WDFN-8L 3x3 Pin Configurations BOOT PWM NC VCC UGATE PHASE LGATE GND 4 5 BOOT PWM NC VCC UGATE PHASE LGATE GND GND 4 5 BOOT PWM VCC UGATE PHASE GND LGATE NC GND Marking Information 03 : Product Code YMDNN : Date Code RT9624BZS : Product Number YMDNN : Date Code RT9624BZSP : Product Number YMDNN : Date Code 03 YM DNN RT9624BZQW RT9624BZS RT9624BZSP RT9624B ZSYMDNN RT9624B ZSPYMDNN Lead Plating System Z : ECO (Ecological Element with Halogen Free and Pb free) RT9624B Package Type S : SOP-8 SP : SOP-8 (Exposed Pad-Option1) QW : WDFN-8L 3x3 (W-Type)

DS9624B-07 July 2015 www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Function Block Diagram Function Pin Description Pin No. SOP-8 SOP-8 (Exposed Pad) / WDFN-8L 3x3 Pin Name Pin Function 1 1 BOOT Bootstrap Supply for High Side Gate Drive. 2 2 PWM PWM Signal Input. Connect this pin to the PWM output of the controller. 3 3 NC No Internal Connection. 4 4 VCC Supply Voltage Input. 5 5 LGATE Low Side Gate Driver Output. Connect this pin to the Gate of low side power N-MOSFET. 6 6, 9 (Exposed Pad) GND Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. 7 7 PHASE Connect this pin to the Source of the high side N-MOSFET and the Drain of the low side N-MOSFET. 8 8 UGATE High Side Gate Drive Output. Connect this pin to the Gate of high side power N-MOSFET. Shoot-Through Protection Turn Off Detection Shoot-Through Protection Tri-State Detect VCC PWM Internal VDD BOOT UGATE PHASE LGATE GND VCC POR Bootstrap Control

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Operation POR (Power On Reset) POR block detects the voltage the VCC pin. When the VCC pin voltage is higher than POR rising threshold, POR block output is high. POR output is low when VCC is not higher than POR rising threshold. When the POR block output is high, UGATE and LGATE can be controlled by PWM input voltage. If the POR block output is low, both UGATE and LGATE will be pulled to low. Tri-State Detect When both POR block output and EN pin voltages are high, UGATE and LGATE can be controlled by PWM input. There are three PWM input modes, which are high, low, and shutdown state. If PWM input is within the shutdown window, both UGATE and LGATE output are low. When PWM input is higher than its rising threshold, UGATE is high and LGATE is low. When PWM input is lower than its falling threshold, UGATE is low and LGATE is high. Bootstrap Control Bootstrap control block controls the integrated bootstrap switch. When LGATE is high (low side MOSFET is turned on), the bootstrap switch is turned on to charge the bootstrap capacitor connected to BOOT pin. When LGATE is low (low side MOSFET is turned off), the bootstrap switch is turned off to disconnect VCC pin and BOOT pin. Turn-Off Detection Turn-off detection block detects whether high side MOSFET is turned off by monitoring PHASE pin voltage. To avoid shoot through between high side and low side MOSFETs, low side MOSFET can be turned on only after high side MOSFET is effectively turned off. Shoot-Through Protection Shoot-through protection block implements the dead time when both high side and low side MOSFETs are turned off. With shoot-through protection block, high side and low side MOSFET are never turned on simultaneously. Thus, shoot through between high side and low side MOSFETs is prevented.

DS9624B-07 July 2015 www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Absolute Maximum Ratings (Note 1)  PHASE to GND  LGATE to GND  UGATE to GND  Power Dissipation, PD @ TA = 25°C  Package Thermal Resistance (Note 2)  ESD Susceptibility (Note 3) Recommended Operating Conditions (Note 4)

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Note 1. Stresses beyond those listed “Absolute Maximum Ratings ” may cause permanent damage to the device. These are stress ratings only, and 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 may affect device reliability. Note 2. θ JA is measured at T A = 25 °C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is measured at the exposed pad of the package. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions.

Electrical Characteristics

Parameter Symbol Test Conditions Min Typ Max Unit Power Supply Power Supply Voltage V CC 4.5 -- 13.2 V Power Supply Current I VCC V BOOT = 12V, PWM Input Floating -- 120 -- A Power On Reset (POR) POR Rising Threshold VPOR_r VCC Rising -- 4 4.4 V POR Falling Threshold VPOR_ f VCC Falling 3 3.5 -- V PWM Input Maximum Input Current I PWM PWM = 0V or 5V -- 160 -- A PWM Floating Voltage VPW M_fl PWM = Open -- 1.8 -- V PWM Rising Threshold VPW M_rth 2.3 2.8 3.2 V PWM Falling Threshold VPW M_fth 0.7 1.1 1.4 V Timing UGATE Rising Time t UGATEr 3nF Load -- 25 -- ns UGATE Falling Time t UGATEf 3nF Load -- 12 -- ns LGATE Rising Time t LGATE r 3nF Load -- 24 -- ns LGATE Falling Time t LGATEf 3nF Load -- 10 -- ns tUGATEpdh -- 60 -- UGATE Propagation Delay tUGATEpdl VBOOT  VPHASE = 12V See Timing Diagram -- 22 -- ns tLGATE pdh See Timing Diagram -- 30 -- LGATE Propagation Delay tLGATE pdl See Timing Diagram -- 8 -- ns Output UGATE Drive Source R UGATEsr V BOOT  VPHASE = 12V , ISo urce = 100mA -- 1.7 --  UGATE Drive Sink R UGATEsk V BOOT  VPHASE = 12V , ISi nk = 100mA -- 1.4 --  LGATE Drive Source R LGATEsr I Source = 100mA -- 1.6 --  LGATE Drive Sink R LGATEsk I Sink = 100mA -- 1.1 --  (VCC = 12V, TA = 25°C unless otherwise specified)

DS9624B-07 July 2015 www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Typical Application Circuit Timing Diagram PWM UGATE LGATE tUGATEpdh tLGATEpdl tUGATEpdl tLGATEpdh 90% 90% 1.5V 1.5V 1.5V 1.5V VCC PWM GND BOOT UGATE PHASE LGATE RT9624B 12V PWM Controller + VOUT CBOOT R1 R2 R4 R5 VIN 2.2 1µF 1µF 2.2 1µH 2.2 3.3nF 2200µF x 2 10µF x 2 1000µF x 3 10µF x 4 12V

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Typical Operating Characteristics Time (20ns/Div) Dead Time No Load (5V/Div) UGATE PHASE LGATE Time (20ns/Div) Dead Time No Load (5V/Div) UGATE PHASE LGATE Time (20ns/Div) PWM Rising Edge UGATE (20V/Div) PHASE (10V/Div) PWM (10V/Div) LGATE (10V/Div) Time (20ns/Div) Dead Time (5V/Div) UGATE PHASE LGATE Full Load Time (20ns/Div) Dead Time (5V/Div) Full Load UGATE PHASE LGATE Time (20ns/Div) PWM Falling Edge UGATE (20V/Div) PHASE (10V/Div) PWM (10V/Div) LGATE (10V/Div)

DS9624B-07 July 2015 www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Time (20ns/Div) Short Pulse No Load UGATE PHASELGATE UGATE − PHASE (5V/Div)

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation.

Application Information

The RT9624B is a high frequency, synchronous rectified, single phase dual MOSFET driver containing Richtek's advanced MOSFET driver technologies. The RT9624B is designed to be able to adapt from normal MOSFET driving applications to high performance CPU VR driving capabilities. Supply Voltage and Power On Reset The RT9624B can be utilized under both VCC = 5V or VCC = 12V applications which may happen in different fields of electronics application circuits. In terms of efficiency, higher V CC equals higher driving voltage of UGATE/LGATE which may result in higher switching loss and lower conduction loss of power MOSFETs. The choice of V CC = 12V or VCC = 5V can be a tradeoff to optimize system efficiency. The RT9624B is designed to drive both high side and low side N-MOSFET through external input PWM control signal. It has power on protection function which held UGATE and LGATE low before the VCC voltage rises to higher than rising threshold voltage. Tri-state PWM Input After the initialization, the PWM signal takes the control. The rising PWM signal first forces the LGATE signal to turn low then UGATE signal is allowed to go high just after a non-overlapping time to avoid shoot through current. The falling of PWM signal first forces UGATE to go low. When UGATE and PHASE signal reach a predetermined low level, LGATE signal is allowed to turn high. The PWM signal is acted as “ High” if the signal is above the rising threshold and acted as “ Low” if the signal is below the falling threshold. When PWM signal level enters and remains within the shutdown window, the output drivers are disabled and both MOSFET gates are pulled and held low. If the PWM signal is left floating, the pin will be kept around 1.8V by the internal divider and provide the PWM controller with a recognizable level. Internal Bootstrap Power Switch The RT9624B builds in an internal bootstrap power switch to replace external bootstrap diode, and this can facilitate PCB design and reduce total BOM cost of the system. Hence, no external bootstrap diode is required in real applications. Non-overlap Control To prevent the overlap of the gate drivers during the UGATE pull low and the LGATE pull high, the non-overlap circuit monitors the voltages at the PHASE node and high side gate drive (UGATE-PHASE). When the PWM input signal goes low, UGATE begins to pull low (after propagation delay). Before LGATE is pulled high, the non-overlap protection circuit ensures that the monitored voltages have gone below 1.1V. Once the monitored voltages fall below 1.1V, LGATE begins to turn high. By waiting for the voltages of the PHASE pin and high side gate driver to fall below 1.1V, the non-overlap protection circuit ensures that UGATE is low before LGATE pulls high. Also to prevent the overlap of the gate drivers during LGATE pull low and UGATE pull high, the non-overlap circuit monitors the LGATE voltage. When LGATE goes below 1.1V, UGATE goes high after propagation delay. Driving Power MOSFETs The DC input impedance of the power MOSFET is extremely high. When V gs1 or Vgs2 is at 12V or 5V, the gate draws the current only for few nano-amperes. Thus once the gate has been driven up to “ ON” level, the current could be negligible. However, the capacitance at the gate to source terminal should be considered. It requires relatively large currents to drive the gate up and down 12V (or 5V) rapidly. It is also required to switch drain current on and off with the required speed. The required gate drive currents are calculated as follows.

DS9624B-07 July 2015www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Outline Dimension A BJ F H M C D I 8-Lead SOP Plastic Package Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 4.801 5.004 0.189 0.197 B 3.810 3.988 0.150 0.157 C 1.346 1.753 0.053 0.069 D 0.330 0.508 0.013 0.020 F 1.194 1.346 0.047 0.053 H 0.170 0.254 0.007 0.010 I 0.050 0.254 0.002 0.010 J 5.791 6.200 0.228 0.244 M 0.400 1.270 0.016 0.050

DS9624B-07 July 2015 www.richtek.com ©Copyright 2015 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. A BJ F H M C D I Y X EXPOSED THERMAL PAD (Bottom of Package) 8-Lead SOP (Exposed Pad) Plastic Package Dimensions In Millimeters Dimensions In Inches Symbol Min Max Min Max A 4.801 5.004 0.189 0.197 B 3.810 4.000 0.150 0.157 C 1.346 1.753 0.053 0.069 D 0.330 0.510 0.013 0.020 F 1.194 1.346 0.047 0.053 H 0.170 0.254 0.007 0.010 I 0.000 0.152 0.000 0.006 J 5.791 6.200 0.228 0.244 M 0.406 1.270 0.016 0.050 X 2.000 2.300 0.079 0.091 Option 1 Y 2.000 2.300 0.079 0.091 X 2.100 2.500 0.083 0.098 Option 2 Y 3.000 3.500 0.118 0.138

DS9624B-07 July 2015www.richtek.com Richtek Technology Corporation 14F, No. 8, Tai Yuen 1st Street, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5526789 Richtek products are sold by description only. Richtek reserves the right to change the circuitry and/or specifications without notice at any time. Customers should obtain the latest relevant information and data sheets before placing orders and should verify that such information is current and complete. Richtek cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Richtek product. Information furnish ed by Richtek is believed to be accurate and reliable. However, no responsibility is assumed by Richtek or its subsidiaries for its use; nor for any infringeme nts of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of R ichtek or its subsidiaries. Dimensions In Millimeters Dimensions In Inches Symbol 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 0.200 0.300 0.008 0.012 D 2.950 3.050 0.1 16 0.120 D2 2.100 2.350 0.083 0.093 E 2.950 3.050 0.1 16 0.120 E2 1.350 1.600 0.053 0.063 e 0.650 0.026 L 0.425 0.525 0.017 0.021 W-Type 8L DFN 3x3 Package 1 122 Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. DETAIL A Pin #1 ID and Tie Bar Mark Options D E A L be SEE DETAIL A