Synchronous Buck Converter GS92D2 Features General Description  10V~36V Input Voltage Range The GS92D2 is a synchronous Buck converter.  Fixed 5.1V Output Voltage Features include wide input voltage range, dual  Programmable Operation Frequency from channel accurate OCP, build-in wire drop compensation and auto-restart after protections. 50KHz~300KHz The GS92D2 has fast dynamic transient  Dual Channel Accurate OCP response with COT control scheme and also has  COT Control with Internal ripple injection good line and load regulation with internal ripple  Programmable Protection Auto-restart Time injection.  Build-in Wire Drop Compensation The GS92D2 provide dual channel accurate OCP.  Selectable CCM/DEM Operation When OCP is detected in channel, the output is  Output Short-Circuit Protection disabled until ART timing is over, and then the  Output Over-Voltage Protection chip will restart automatically, which make sure  Output Under-Voltage Protection the safety of whole system. Wire drop  Over Temperature Protection compensation is also provided to compensate the  QFN23-4x4 Package voltage loss in cable transmission.  Green Product (RoHS, Lead-Free, Other protections include over-voltage protection, under-voltage protection, short-circuit protection Halogen-Free Compliant) and over-temperature protection. The GS92D2 is available in QFN23-4x4 package. Applications  Car Charger  Portable Charger Devices  Automotive Power Application  General-Purposed DC-DC Converters This document is GStek's confidential information. Anyone having confidential obligation to GStek shall keep this document confidential. Any unauthorized disclosure or use beyond authorized purpose will be considered as violation of confidentiality and criminal and civil liability will be asserted. Green Solution Technology Co., LTD. 1 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Typical Application Figure 1 Typical Application of GS92D2 Green Solution Technology Co., LTD. 2 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Function Block Diagram VIN TON VIN VDC BOOT 8,9 6 22 21 20 10,11, 17,18 LX Pre Reg 12~16, EN 5 Enable Bandgap VREF Soft Start DRV 19 CFB 7 DRV VOUT 2 Divider VCC UVLO LDO UVLO PGND Timming ART 1 TON Gate Control Generator Logic 115% Error OVP Protection 70% AMP UVP Logic Error AMP PWMError AMP ZCD CMP VREF Ripple Injection 13 OCP\&WDC VSS 34 CS1 CS2 Figure 2 Function Block Diagram Green Solution Technology Co., LTD. 3 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Pin Configuration ( Top view ) Figure 3 QFN23-4x4 Package Pin Descriptions I/O Description I Setting auto-restart time. Connect a capacitor to VSS No. Name 1 ART I/O Output voltage feedback pin. Connect to output capacitor. 2 VOUT I Channel 1 current sense. 3 CS1 I Channel 2 current sense. 4 CS2 Enable Control Pin. EN=Low, Shutdown; EN=High, I 5 EN Auto-DEM Mode; EN=Floating, Forced CCM. I On time setting. Connect a resistor to VIN. 6 TON I Feedback pin. 7 CFB I Chip power supply for Power MOSFET. 8,9,22,24 VIN Upper driver floating ground and used to sense the current of I 10,11,17,18,25 LX inductor. I Power ground for Power MOSFET. 12~16,19 PGND Green Solution Technology Co., LTD. 4 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 20 BOOT I/O Power supply for high-side driver. Connect a 0.1uF capacitor between BOOT and LX. 21 VDC I/O Internal output regulator. Connect a capacitor to VSS 23 VSS I/O Ground pin for internal circuit. Ordering Information GS92D2PP-R 1. Package 2. Shipping No Item Contents 1 Package QF: QFN23-4x4 2 Shipping R: Tape \& Reel Example: GS92D2 QFN23-4x4 Tape \& Reel ordering information is “GS92D2QF-R” Green Solution Technology Co., LTD. 5 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Absolute Maximum Rating (Note 1) Symbol Limits Units Parameter VIN -0.3 ~ 40 V VTON -0.3 ~ 40 V VIN to GND VCS1,2 -0.3 ~ 6 V TON to GND VDC -0.3 ~ 6 V CS to GND VART -0.3 ~ 6 V VDC to GND VEN -0.3 ~ 40 V ART to GND VOUT/VFB -0.3 ~ 6 V EN to GND VBOOT-GND -0.3 ~ 46 V VOUT/VFB to GND VBOOT-LX -0.3 ~ 6 V BOOT Voltage - 0.7V~40V (DC) BOOT to LX Voltage VLX -8V~40V(<200nS) V LX to GND PD_QFN23-4x4 3546 mW TJ - 45 ~ 150 °C Package Power Dissipation at TA≦25°C TSTG - 55 ~ 150 °C Junction Temperature °C Storage Temperature TLEAD 260 V Lead Temperature (Soldering) 10S VESD_HBM 2K V ESD (Human Body Mode) (Note 2) VESD_MM 200 ESD (Machine Mode) (Note 2) Thermal Information (Note 3) Symbol Limits Units θJA_QFN23-4x4 28.2 °C/W Parameter Thermal Resistance Junction to Ambient Recommend Operating Condition (Note 4) Parameter Symbol Limits Units VIN to GND (Note 5) VIN 10~36 V VDC to GND VDC 4.5~5.5 V EN to GND VEN VEN= VIN V Junction Temperature TJ -40 ~125 °C Ambient Temperature TA -40 ~ 85 °C Green Solution Technology Co., LTD. 6 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Electrical Characteristics (RTON=1MEGOhm, VIN=12V, EN=Floating, TA =25°C, unless otherwise specified) Parameter Symbol Conditions Min Typ Max Units Supply Voltage (VIN) Under voltage lock out VIN_UVLO   9 V (Rising) 0.7 V UVLO Hysteresis VIN_UVLOHYS   V 5V Pre-regulator (VDC) V V Output Voltage VDC   5.15 Under voltage lock out VVDC_UVLO   4.3 V (Rising) 0.3 uA mA UVLO Hysteresis VVDC_UVLOHYS   Vout Section V V Vout Reference Voltage VOUT_R   5.1 V 70 uA Vout Operation Current IOUT_OP   10 uA Vout Discharge Current IOUT_DIS   mV EN Logic us uA EN Logic Low Voltage VEN_L EN Falling     0.6 uA EN Floating Voltage VEN_F EN Rising   1.7   uA uA EN Logic High Voltage VEN_H PFM Falling 3.1     EN Logic High Input IEN_H PFM Rising us Current   14 EN Logic Low Input Current IEN_L   -2 -1   Accurate OCP(CS1/CS2) OCP Threshold VOCP   100.5 108 115.5 5 OCP Delay TOCP       0.01 CS Sinking Current ICS_OFF EN=0 2.2 ICS_ON EN=Floating Current Parameters(VIN) Quiescent Current IQ VOUT=5.5V, VIN=12V   760 Shutdown Current IOFF EN=0, VIN=12V  4 System Time On-Time TON VIN=12V,VOUT=4.8V 3.9 Green Solution Technology Co., LTD. 7 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 TON Current ITON_OFF VIN=12V,EN=0V    0.01 ITON_ON VIN=12V,EN=12V 11.3 uA VIN=12V,VOUT=4.8V 450 ns Minimum Off-Time TOFFMIN   2.6 ms Softstart Time   2 V Internal Softstart Time TSS   2 uA Auto Restart Section VART=1.8V 1.5 mA Auto-restart Threshold VART BOOT-LX=5V   25   mohms Voltage     10   uA   11   mohms ART charging Current IART_CHG VDC-GND=5V   10   uA ART discharging IART_DIS   Current 6.3 A GND-LX ;FSW=100K,L=10uH -10   10 mV Driver Section GND-LX 70 % High Side MOS RDSON RDSH   20 us   115 % High Side Leakage ILEAKH   20 us   Low Side MOS RDSON RDSL   150   °C     °C Low Side Leakage ILEAKL   20 LX Current Sensing   ohms   80 Current Limit ILIM VIN to BOOT, 10mA Zero Crossing VZCD Threshold Voltage Fault Protection UV Threshold VUV_TH UV Fault Delay TUV_D OVP Threshold VOV_TH OVP Delay TOV_D Over Temperature Shutdown Thermal Shutdown TTSDN Threshold Thermal Shutdown THYS_TSDN Hysteresis Bootstrap Diode Internal Boost Charging RBT_D Switch On-Resistance Green Solution Technology Co., LTD. 8 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Wire Drop Compensation Wire Drop RWDC VART=1V 120 mv Compensation Rate (VOUT-VCS=100mV) Short Protection When Start Up Short Protection Delay TSP VOUT=0.4V 1 ms Time 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.Devices are ESD sensitive. Handling precaution recommended. Note 3.θJA is measured in the natural convection at TA=25°C on a high effective thermal conductivity test board (4 Layers, 2S2P) of JEDEC 51-7 thermal measurement standard. Note 4.The device is not guaranteed to function outside its operating conditions. Note 5.Recommend the Pulse time<100ns when VIN over than 40V. Note 6.If V(BOOT)-V(LX)<4V, a boot diode is recommended. Green Solution Technology Co., LTD. 9 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Application Information to TON pin. For heavy load application, due to ground bounced and The GS92D2 is a synchronous Buck Converter the high impedance of RTON, the TON pin should always with COT control scheme. Features include wide be bypassed to AGND using a several nF-order input voltage range, dual channel accurate OCP, ceramic capacitor for reliable system operation. wire drop compensation and programmable timing EN Control and Mode Selection of auto-restart after protections. The EN pin enables the power supply. When EN is tied System Clock Generator and PWM Control to VIN, the GS92D2 is enabled and operated in The on-time of GS92D2 can be set by an external diode-emulated mode (DEM, which is power-saving). setting resistor from VIN to TON, thus the GS92D2 When EN is floating, the GS92D2 is also enabled but based Buck converter has a relative constant operated in CCM. operation frequency over wide input voltage range. In DEM mode, when the load turns light, the GS92D2 At the beginning of each switching cycle, upper maintains the on-time and extend the off-time, which power MOSFET is turned on, after typical fixed decrease the system clock frequency to skip PWM on-time, the upper MOSFET is turned off, and then pulses for better efficiency. When DEM is enabled, the lower power MOSFET is turned on after internal GS92D2 zero crossing detector will sense the inductor dead time. The upper MOSFET will not be turned on current from LX pin and judge its value by comparing at the beginning of next cycle until output voltage falls the LX pin voltage to ground. Once the LX node voltage down below the preset voltage. is equal to the PGND node voltage, the converter will To avoid the surge inductor current during large load turn off the low side power MOSFET and enter DEM. As transient, a minimum Off-time is added. Typical the load current decrease, it takes longer time to minimum off-time is around 450ns. discharge the output capacitor to the level that required High Side Switch On-Time Count to start the next switching cycle. The on-time is kept the The on-time is decided by the external setting same as in the heavy-load operation. resistor, and the input voltage. Looking at the TON If the EN pin is pulled low, the GS92D2 will be shut pin, the input voltage is converted to current which is down and discharge the output capacitor through the inversely proportional to itself by dividing the external VOUT pin. Since this is a soft discharge, there is no setting resistor. The TON current is used to charge dangerous negative voltage excursion to be concerned an internal capacitor and when the voltage of the about. In order to maintain the correct function of the capacitor reaches the internal voltage which is soft-discharge module, the chip power supply must be proportional to output voltage, on-time one-shot online. pulse is generated, and then upper power MOSFET Accurate Over Current Protection is turned off and lower power MOSFET is turned on. The accurate OCP is implemented by the CS1 and CS2 We can count the on-time and switching frequency pins. OCP is triggered and shuts down UG and LG if according to the equations below: (VOUT-VCS1) or (VOUT-VCS2) is higher than 108mv TON=(VOUT×RTONx8.93p) / (VIN-0.8) (Typical), thus the OCP threshold can be set by the Then, the switching frequency is: following equation: Fsw=VOUT/ (VIN×TON) RTON is a resistor connected from input voltage (VIN) 10 Aug-15 Green Solution Technology Co., LTD. Rev.:0.1

Synchronous Buck Converter GS92D2 IOCP=108mv/RS module delays about 20us and turns on the low-side RS is the sense resistor connected between VOUT Power MOSFET. The state is maintained until the ART pin and CS pin. The OCP has 5us de-bounce time. timing is over, and the GS92D2 will restart. When OCP is triggered, the GS92D2 will enter a Output Under-Voltage Protection auto-restart procedure: delay a time period and When the VOUT voltage falls down to 70% of the rebuild the output from soft start. The delay time can normal operating voltage, the internal fault-logic module be set by ART pin. will delay about 20us and turns on the low-side Power Auto-restart Setting MOSFETs. The state is maintained until the ART timing The GS92D2 will auto-restart when protections is over, and the GS92D2 will restart. UVP is disabled occurred. Before restart, a delay time period can be during soft start. set by connecting a capacitor from ART pin to VSS VDC and VIN UVLO pin. A current will charge the capacitor from ground An internal under voltage lockout (UVLO) module is level to a preset level. The delay time is calculated by used to sense the VDC power supply. The PWM the following equation: converter is forbidden by the under voltage lockout TART=1E6*CART module. When VDC rises above 4.3V, the GS92D2 will Wire Drop Compensation initial the control logic circuitries and soft-start ramping The GS92D2 will compensate the cable voltage drop generator, and then allows switching to occur. When due to the output current. The output current is VDC falls below 4.0V, the PWM converter is forbidden. sensed by CS1 pin and CS2 pin as mentioned before. When VIN rises above 9V, the LDO output voltage The GS92D2 will choose the larger output current to (VDC) of GS92D2 enables and regulates a 5.15V compensate if the current of two channels are voltage. After VIN falls below 8.3V the LDO (VDC) will different. turn off. Current Limit Short Circuit Protection The GS92D2 uses the on-state resistance of the During soft start, if short circuit occurs, the output low-side power MOSFET as a current-sense resistor current will increase rapidly to current limit and the state to sense the inductor current. In this case, the maintained until soft start finished, which makes the GS92D2 build in a cycle-by-cycle current limit. The external components endure a big stress. The GS92D2 current limit circuit regulates the inductor valley offers rapid protections when short circuit occurred current that means if the valley value of the inductor during soft start. current exceeded a preset level the PWM is not VOUT Pin allowed to initiate a new switching cycle. The VOUT pin offers feedback information of output During soft-start, the GS92D2 will linearly release the voltage, which makes the ton more accurate, so the current limit according to the internal soft-start ramp. switching frequency variation is very small even when The current limit will be fully released about 1ms after the GS92D2 operates in a very wide input voltage soft start begun. range. When any fault condition occurs, the VOUT pin Output Over-Voltage Protection provides a discharge path from output to ground. When the VOUT voltage rises up to 115% of the Choose Inductor normal operating voltage, the internal fault-logic Set the ripple current approximately 1/4 to 1/2 of the Green Solution Technology Co., LTD. 11 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 maximum output current. 1/3 is recommended. LIND  1 f  (VIN(max)  VOUT ) VOUT IIND(ripple) VIN (max) LIND  3  (VIN(max)  VOUT ) VOUT IIOUT (max)  f VIN (max) For applications that require fast transient response with minimum VOUT overshoot, consider a smaller inductance than above. The cost of a small inductance value is higher steady state ripple, larger line regulation, and higher switching loss. The inductor also needs to have low DCR to achieve good efficiency, as well as enough room above peak inductor current before saturation. The peak inductor current can be estimate as follows. LIND( peak )  1  (VIN (max)  VOUT ) VOUT  VCL L f VIN (max) RDS (on) Choose Output Capacitors RESR  1  0.038 I ripple  3  0.038 I OUT (max) RESR  VOUT 114(mohm) I OUT (max) Organic semiconductor capacitors or specialty polymer capacitors are recommended. Green Solution Technology Co., LTD. 12 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 Package Dimensions, QFN23-4x4 L2 E1 D1 Ek E3 D2 D1 E2 D3 L pin 1 dot L1 21 L1 eb A A1 D (Bottom view) (Top view) A3 (Side view) Symbol Dimensions in Millimeters A A1 Min. Max. A3 0.80 0.90 b 0.00 0.05 D D1 0.203 REF. D2 0.20 0.30 D3 3.90 4.10 E 0.65 0.85 E1 0.85 1.05 E2 1.24 1.44 E3 3.90 4.10 L 2.95 3.15 L1 2.60 2.70 L2 2.95 3.15 e 0.35 0.45 k 0.57 0.67 0.23 0.33 0.50 REF. 0.33 - Note 1. Min.: Minimum dimension specified. 2. Max.: Maximum dimension specified. 3. REF.: Reference. Normal/Regular dimension specified for reference. Green Solution Technology Co., LTD. 13 Aug-15 Rev.:0.1

Synchronous Buck Converter GS92D2 DISCLAIMERS Please read the notice stated in this preamble carefully before Admission e accessing any contents of the document attached. Admission of GStek’s statement therein is presumed once the document is released to the receiver.   Notice:    Firstly,  GREEN  SOLUTION  CO.,  LTD.  (GStek)  reserves  the  right  to  make  corrections,  modifications,  enhancements,  improvements,  and  other changes to its information herein without notice.. And the aforesaid information does not form any part or parts of any quotation or  contract between GStek and the information receiver.       Further, no responsibility is assumed for the usage of the aforesaid information. GStek makes no representation that the interconnect  of  its  circuits  as  described  herein  will  not  infringe  on  exiting  or  future  patent  rights  and  other  intellectual  property  rights,  nor  do  the  descriptions contained herein express or imply that any licenses under any GStek patent right, copyright, mask work right, or other GStek  intellectual property right relating to any combination, machine, or process in which GStek products or services are used.    Besides, the product in this document is not designed for use in life support appliances, devices, or systems where malfunction of this  product can reasonably be expected to result in personal injury. GStek customers’ using or selling this product for use in such applications  shall do so at their own risk and agree to fully indemnify GStek for any damage resulting from such improper use or sale.    At last, the information furnished in this document is the property of GStek and shall be treated as highly confidentiality; any kind of  distribution, disclosure, copying, transformation or use of whole or parts of this document without duly authorization from GStek by prior  written  consent  is  strictly  prohibited.  The  receiver  shall  fully  compensate  GStek  without  any  reservation  for  any  losses  thereof  due  to  its  violation of GStek’s confidential request. The receiver is deemed to agree on GStek’s confidential request therein suppose that said receiver  receives  this  document  without  making  any  expressly  opposition.  In  the  condition  that  aforesaid  opposition  is  made,  the  receiver  shall  return this document to GStek immediately without any delay.  Green Solution Technology Co., LTD. 14 Aug-15 Rev.:0.1