® RT9483 Easy to Use Power Bank Solution (EZPBSTM) Integrated Chip with One Port Output General Description Features The RT9483 is a high integration and easy to use power solution for Li-ion power bank and other powered handheld applications. We call it EZPBSTM (Easy to Use Power Bank Solution). This single chip includes a linear charger, a synchronous Boost with output load management and a torch function support. The battery volume and the state of charging and discharging can be indicated by 4LEDs. The RT9483 is available in the WQFN-24L 4x4 package. EZPBSTM (Easy to Use Power Bank Solution) Charger Applications Li-ion Power Bank Ordering Information Serial Number Package Type QW : WQFN-24L 4x4 (W-Type) (Exposed Pad-Option 2) Auto and Button Control Sync-Boost Total Output Current up to 2.5A Peak Efficiency 97% Battery State of Charge (SOC) Indicator Lead Plating System G : Green (Halogen Free and Pb Free) Note : Richtek products are : Battery SOC Detection Support NTC for Battery Temperature Sensing 4LEDs for Battery SOC Display RoHS compliant and compatible with the current require- Other Functions ments of IPC/JEDEC J-STD-020. One Linear Charger up to 1.2A DPM Function (Dynamic Power Management) Thermal Regulation Auto-Recharge Support JEITA Function USB Output RT9483 Compact BOM Elements with EZPBSTM Single Chip Protection Functions (OTP, OVP, OCP, VBUS and Output Short Protection) Support Charging and Discharging at the same time by Smart Algorithm Suitable for use in SnPb or Pb-free soldering processes. Torch Functions Simplified Application Circuit Input Power VBUS CIN RT9483 VBAT Battery CBAT L1 Battery LXBST SWIN C1 VMID CVMID DS9483-01 September 2014 LEDx TORCH BUTTON Copyright © 2014 Richtek Technology Corporation. All rights reserved. USBOUT1 USB Port 1 LED Indicator Torch Function GND is a registered trademark of Richtek Technology Corporation. www.richtek.com 1 RT9483 Pin Configurations Marking Information (TOP VIEW) VBUS PGNDBST PGNDBST LXBST LXBST VMID 2F= : Product Code 2F=YM DNN YMDNN : Date Code 24 23 22 21 20 19 VBAT TS LED1 LED2 LED3 LED4 1 18 2 17 3 16 GND 4 15 25 5 14 13 6 8 9 10 11 12 NC NC GND TORCH BUTTON TP1 7 USBOUT1 USBOUT1 SWIN NC NC TP2 WQFN-24L 4x4 Product Name List Serial Number Product Name Auto/Button SOC LED Number Programmable Battery Regulation AA02 RT9483GQW-AA01 Auto 4LEDs Disable 4.2V AA02 RT9483GQW-AA02 Button 4LEDs Disable 4.2V AB01 RT9483GQW-AB01 -- -- Enable -- * : Please refer to application note. -- : Set by program Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 2 is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 Functional Pin Description Pin No. Pin Name Pin Function 1 VBAT Battery Charge Current Output. 2 TS Battery Temperature Sense Setting. 3 LED1 Current Sink Output for LED1. 4 LED2 Current Sink Output for LED2. 5 LED3 Current Sink Output for LED3. 6 LED4 Current Sink Output for LED4. NC No Internal Connection. GND Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation. 10 TORCH Current Sink Output for Torch LED Function. Open Drain Output 11 BUTTON Button Control Input for mode change. 12 TP1 Connected to GND. 13 TP2 Connected to GND. 16 SWIN Used for Internal. USBOUT1 USB-1 Power Output. 19 VMID Boost Output. 20, 21 LXBST Boost Switch Output. 22, 23 PGNDBST Boost Power GND. VBUS VBUS Power Supply. 7, 8, 14, 15 9, 25 (Exposed Pad) 17, 18 24 Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 September 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 3 RT9483 Function Block Diagram VBUS USBOUT1 Linear Charger 1.2A VBAT USB-1 Load Manager Up to 2.1A SWIN TS VMID LXBST Central Control PGNDBST 1. Battery Capacity Detection 2. Protection 3. LED Display 4. Mode Control 5. Button Operation BUTTON TORCH Torch Brightness Control (Open Drain) LED1 LED2 LED3 LED4 TP1 TP2 GND Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 4 is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 Operation The RT9483 is a high integrated IC for Li-Ion battery power bank. It includes a linear charger 1.2A, a synchronous Boost 5.1V, an output load management, LED indicator and torch function. Change Current Base on thermal regulation function, the charging current can support up to 1.2A. VBUS OVP If the input voltage (VBUS) is higher than the threshold voltage VOVP, the internal OVP signal will go high and the charger will stop charging until VIN is below VOVP − ΔVOVP. The converter has an over-temperature protection. When the junction temperature is higher than the thermal shutdown rising threshold, the system will be latched and the output voltage will no longer be regulated until the junction temperature drops under the falling threshold. Output Short Protection When output short to ground, the system will be latched and the output voltage will no longer be regulated until power reset. CC/CV/TR Multi Loop Controller There are constant current loop, constant voltage loop and thermal regulation loop to control the charging current. VMID OVP If the internal voltage (VMID) is higher than the threshold voltage VOVP, the internal OVP signal will go high and the charger will stop charging until VMID is below VOVP −ΔVOVP. OCP The converter senses the current signal when the highside P-MOSFET turns on. As a result, The OCP is cycle by-cycle current limitation. If the OCP occurs, the converter holds off the next on pulse until inductor current drops below the OCP limit. Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 OTP September 2014 Too Hot or Too Cold The temperature sense input TS pin can be connected a thermistor to determine whether the battery is too hot or too cold for charging operation. If the battery's temperature is out of range, charging is paused until it re-enters the valid range. is a registered trademark of Richtek Technology Corporation. www.richtek.com 5 RT9483 Absolute Maximum Ratings (Note 1) Supply Voltage, VBAT -------------------------------------------------------------------------------------- −0.3V to 6V Supply Voltage, VBUS ------------------------------------------------------------------------------------- −0.3V to 10V Supply Voltage USBOUT1 (100μs) ---------------------------------------------------------------------- −0.3V to 10V LED Output Voltage, LED1, LED2, LED3, LED4 ---------------------------------------------------- −0.3V to 10V TORCH --------------------------------------------------------------------------------------------------------- −0.3V to 10V Other Pins ----------------------------------------------------------------------------------------------------- −0.3V to 6V Power Dissipation, PD @ TA = 25°C WQFN-24L 4x4 ---------------------------------------------------------------------------------------------- 3.57W Package Thermal Resistance (Note 2) WQFN-24L 4x4, θJA ----------------------------------------------------------------------------------------- 28°C/W WQFN-24L 4x4, θJC ---------------------------------------------------------------------------------------- 7.1°C/W Junction Temperature Range ------------------------------------------------------------------------------ 150°C Lead Temperature (Soldering, 10 sec.) ----------------------------------------------------------------- 260°C Storage Temperature Range ------------------------------------------------------------------------------ −65°C to 150°C ESD Susceptibility (Note 3) HBM (Human Body Model) -------------------------------------------------------------------------------- 2kV MM (Machine Model) --------------------------------------------------------------------------------------- 200V Recommended Operating Conditions (Note 4) Supply Input Voltage, VBAT, VBUS --------------------------------------------------------------------- 2.8V to 5.5V Junction Temperature Range ------------------------------------------------------------------------------ −40°C to 125°C Ambient Temperature Range ------------------------------------------------------------------------------ −40°C to 85°C Electrical Characteristics TOP Unit Electrical Characteristics (VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit -- 30 -- A Supply Input Battery Quiescent Current IBAT_sdy for Standby No VBUS, Boost on, Indicator Off. Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 6 Button Mode is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 Charger Unit Electrical Characteristics (VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Supply Input VBUS VBAT VOS Rising VOS_H -- 100 200 mV VBUS VBAT VOS Falling VOS_L 10 50 -- mV VBUS Operating Range VBUS_CHG 4.5 -- 5.5 V VBUS Regulation DPM VDPM = 4.5V 5 -- 5 % VBAT Regulation VREG TA = 0 to 85C, VREG = 4.2V 1 -- 1 % Re-Charge Threshold V RECHG VREG Recharge Level -- 150 -- mV VBUS Power FET RDS(ON) RDS(ON)_chg IBAT = 1A -- 200 300 m Battery Charger Voltage Regulation Current Regulation Fast-Charge Current Accuracy ICHG ICHG = 1.2A 5 -- 5 % Pre-Charge Current Accuracy ICHG_Pre Ratio of Fast-Charge Current 5.5 10 14.5 % Pre-Charge Threshold Vpre VBAT Rising 2.35 2.5 2.65 V Pre-Charge Threshold Hysteresis V pre VBAT Falling 120 200 280 mV ITERMI -- 10 -- % TF_CC -- 24 -- hour Charge Termination Detection Termination Current Ratio Timer Fast-Charge Time Fault Boost Unit Electrical Characteristics (VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Supply Input Output Voltage VOUTBST -- 5.1 -- V Output Voltage Accuracy VOUTBST 5 -- 5 % -- 2.5 -- A IOCP 6 -- -- A f SW 0.4 0.5 0.6 MHz Over-Voltage Protection VMID_OVP 5.6 5.7 6 V Over-Voltage Protection Hysteresis VMID_OVP_hys -- 0.2 -- V Under-Voltage Protection (Short-Circuit Protection) VBST_FBUV -- 3.37 -- V MAX Output Current PFET Peak Current Limit As VBAT > 3.3V, VOUT = 5V Power Switch Switching Frequency Protection Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 September 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 7 RT9483 Others Electrical Characteristics (VBUS = 5V, VBAT = 3.7V, TA = 25°C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit -- 0.75 -- mA -- 200 -- mV LED LED Current Sink ILED Torch Open-Drain Low Voltage VODL_T ISINK = 5mA Button Button Control Press Duty Time Logic-High VIH_B 1.5 -- -- V Logic-Low VIL_B -- -- 0.4 V High-Level TPress_H 0.1 -- -- sec Low-Level TPress_L 0.1 -- -- sec -- 105 -- °C Protection Charger Thermal Regulation TREG For Charger Over-Temperature Protect TOTP -- 150 -- °C Over-Temperature Protect Hysteresis TOTP -- 20 -- °C VBUS OVP Threshold Voltage VOVP VBUS Rising 6.5 6.8 7.1 V VBUS OVP Threshold Voltage Hysteresis VOVP_Hys VBUS Falling -- 200 280 mV VBUS Attached Threshold Voltage VBUS_ATT VBUS Rising 3.8 4 4.2 V VBUS Attached Threshold Voltage Hysteresis VBUS_ATT_Hys VBUS Falling -- 200 280 mV BASE 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. θJA is measured at TA = 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. Note 3. Devices are ESD sensitive. Handling precaution is recommended. Note 4. The device is not guaranteed to function outside its operating conditions. Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 8 is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 Typical Application Circuit RT9483 24 Input Power VBUS VBAT 1 CIN 1µF/25V CBAT 10µF 16 19 CVMID 22µF x 2 SWIN TS VMID USBOUT1 L1 1µH VBAT C1 10µF 22, 23 PGNDBST 11 BUTTON 3 4 D2 LED3 5 D3 6 D4 10 R1 D6 LED2 R2 100k 12 TP1 R3 100k 13 TP2 9, 25 (Exposed Pad) GND LED4 TORCH Copyright © 2014 Richtek Technology Corporation. All rights reserved. September 2014 Li-Bat Prot-IC USB1 Output N-MOSFET VBAT D1 LED1 DS9483-01 17, 18 RNTC 10k Semitec 103AT LXBST Button VBAT 2 COUT1 1µF 20, 21 + - Power Display VMID is a registered trademark of Richtek Technology Corporation. www.richtek.com 9 RT9483 Typical Operating Characteristics USBOUT Voltage vs. Load Current USBOUT Efficiency vs. Load Current 6.0 100 90 70 Output Voltage (V) Efficiency (%) 5.5 VBAT = 3.3V VBAT = 3.7V VBAT = 3.9V 80 60 50 40 30 20 5.0 VBAT = 3.3V VBAT = 3.7V VBAT = 3.9V 4.5 4.0 3.5 10 USBOUT = 5.1V USBOUT = 5.1V, L = 1μH, COUT = 1μF 3.0 0 0 500 1000 1500 2000 0 2500 500 Load Current (mA) USBOUT Voltage vs. Temperature OVP Threshold Voltage (V) Output Voltage (V) 5.4 5.3 5.2 5.1 5.0 VBAT = 3.3V VBAT = 3.7V VBAT = 3.9V 4.8 4.7 4.6 USBOUT = 5.1V 4.5 -50 -25 0 25 50 75 100 7.20 7.12 7.04 6.96 6.88 6.80 6.72 6.64 6.56 6.48 6.40 6.32 6.24 6.16 6.08 6.00 VBAT = Real Battery -50 -25 0 25 50 75 100 Battery Regulation Voltage (V)1 Temperature (°C) Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 10 50 75 100 125 ICHG Thermal Regulation vs. Temperature ICHG Thermal Regulation (mA) VIN = 5V, VBAT = Real Battery 0 25 Temperature (°C) 105°C -25 2500 Falling 125 Battery Regulation Voltage vs. Temperature -50 2000 Rising Temperature (°C) 4.25 4.24 4.23 4.22 4.21 4.20 4.19 4.18 4.17 4.16 4.15 4.14 4.13 4.12 4.11 4.10 1500 VBUS OVP Threshold Voltage vs. Temperature 5.5 4.9 1000 Load Current (mA) 125 1300 1200 1100 1000 900 800 700 600 500 400 300 200 100 0 VIN = 5V, VBAT = Real Battery -50 -25 0 25 50 75 100 125 Temperature (°C) is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 Application Information The RT9483 is a high integrated IC for Li-Ion battery power bank. This chip includes a linear charger, a synchronous Boost, an output load management, LED indicator and torch function. Pre-Charge Mode battery in order to maintain thermal regulation at around 105°C. This operation continues until the junction temperature falls below the thermal regulation threshold (105°C) by the hysteresis level. This feature prevents the maximum power dissipation from exceeding typical design conditions. When the output voltage is lower than 2.3V, the charging current will be reduced to a fast-charge current ratio to protect the battery life time. Time Fault Fast-Charge Mode When time fault happens, the charger cycle will be turned off charging function. When the output voltage is higher than 2.5V, the charging current will be equal to the fast-charge current with 1.2A. Constant-Voltage Mode When the output voltage is near 4.2V, the charging current will fall below the termination current. Re-Charge Mode When the chip is in charge termination mode, the charging current will gradually go down to zero. However, once the voltage of the battery drops to below 4.05V, then the charging current will resume again. Charge Termination When the charge current is lower than the charge termination current ratio (10%) for VBAT > 4.05V and the time is larger than the deglitch time (25ms), it will be latched high unless the power is re-toggled. Input DPM Mode If the input voltage is lower than VDPM (4.5V), the input current limit will be reduced to stop the input voltage from dropping any further. This can prevent the IC from damaging improperly configured or inadequately designed USB sources. The Fast-Charge Fault Time is set by 24hours. Battery Pack Temperature Monitoring The RT9483 features an external battery pack temperature monitoring input. The TS input connects to the NTC thermistor in the battery pack to monitor battery temperature and prevent danger over temperature conditions. If at any time the voltage at TS falls outside of the operating range, charging will be suspended. The NTC thermistor recommends using 10kΩ. JEITA Function For JEITA battery temperature standard : CV regulation voltage will change at the following battery Temp ranges 45°C to 60°C. 4.2V 4.05V 100% Ichg 50% Ichg 0C 10C 45C 60C Temperature Regulation In order to maximize charge rate, the RT9483 features a junction temperature regulation loop. If the power dissipation of the IC results in junction temperature greater than the thermal regulation threshold (105°C), the RT9483 will cut back on the charge current and disconnect the Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 September 2014 Synchronous Step-Up The converter operates in fixed frequency PWM Mode with 500kHz, Continuous Current Mode (CCM), and Discontinuous Current Mode (DCM) with internal MOSFETs. is a registered trademark of Richtek Technology Corporation. www.richtek.com 11 RT9483 Operation Method Button Mode Charge Mode : VBUS in and charging battery Button mode : When external handheld device plug in for power bank, the USBOUT will turns on by button. Discharge Mode : USBOUT in and discharging for handheld Chg-Dchg Mode : VBUS and USBOUT in, charging battery and discharging handheld at the same time Relax Mode : VBUS and USBOUT plug out Button Function Function Button Action Micro-USB Adapter plug-in : ON Charging NA Micro-USB Adapter plug-out : OFF USB slave plug-in : ON Discharging Check Battery Capacity Torch 0.1s 0.1s After unplugging the H/H device, the power bank stops USB slave plug-out : OFF charging the device automatically without pressing the button. Press the button (short press) one time : ON After 20sec : OFF 0.1s 0.1s Press the button (short press), the LED battery indicator lights up. After 20sec, the LED battery indicator fades out. Double click the button (short press) : ON Double click the button (short press), the torch light lights up. Double click the button (short press : OFF Double click the button (short press) again, the torch light fades out. Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 12 Description After plugging in the external power source, the power bank will be charged automatically without pressing the button, and the LED battery indicator lights up at the same time. After unplugging the external power source, the power bank stops being charged automatically without pressing the button, and the LED battery indicator fades out at the same time. After plugging in the H/H device and pressing the button, the power bank starts to charge the device. is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 BUTTON Press Timing LED Indicator Function Define Button (Short/Long) Press Timing About LED indicator, it will follow below table to show SOC. The LED current is 0.75mA. Short press = min (0.1s) Blank = min (0.1s) ●●●● Low→High ● : LED ON, ○ : LED OFF, ● : LED FLASH Battery Voltage SOC LED Flash and Running Timing ●○○○ SOC LED Flash 3700mV 0.5s Operation of Charging ●●○○ ●●●○ ●●●● 0.5s 3700mV 3940mV SOC LED Running ●●○○ ●●● ○ ●●● ● 0.5s 0.5s 3940mV 4100mV ●●● ● 0.5s 4100mV 4200mV ●●●● 4200mV ●●●● Battery Voltage Operation of Discharging 4200mV 3880mV ●●●● 3880mV 3720mV ●●●○ 3720mV 3500mV ●●○○ 3500mV 3200mV 3200mV 2800mV Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 ●●● ○ September 2014 ●○○○ ●○○○ is a registered trademark of Richtek Technology Corporation. www.richtek.com 13 RT9483 Thermal Considerations Layout Consideration For continuous operation, do not exceed absolute maximum junction temperature. The maximum power dissipation depends on the thermal resistance of the IC package, PCB layout, rate of surrounding airflow, and difference between junction and ambient temperature. The maximum power dissipation can be calculated by the following formula : The PCB layout is an important step to maintain the high performance of the RT9483. PD(MAX) = (TJ(MAX) − TA) / θJA where TJ(MAX) is the maximum junction temperature, TA is the ambient temperature, and θJA is the junction to ambient thermal resistance. For recommended operating condition specifications, the maximum junction temperature is 125°C. The junction to ambient thermal resistance, θJA, is layout dependent. For WQFN-24L 4x4 package, the thermal resistance, θJA, is Both the high current and the fast switching nodes demand full attention to the PCB layout to save the robustness of the RT9483 through the PCB layout. Improper layout might show the symptoms of poor line or load regulation, ground and output voltage shifts, stability issues, unsatisfying EMI behavior or worsened efficiency.For the best performance of the RT9483, the following PCB layout guidelines must be strictly followed. Place the input and output capacitors as close as possible to the input and output pins respectively for good filtering. Care should be taken for a proper thermal layout. Wide traces, connecting with vias through the layers, provides a proper thermal path to sink the heat energy created from the device and inductor. Keep the main power traces as wide and short as possible. Recommend as below : 28°C/W on a standard JEDEC 51-7 four-layer thermal test board. The maximum power dissipation at TA = 25°C can be calculated by the following formula : VBUS trace >40mil; The maximum power dissipation depends on the operating ambient temperature for fixed T J(MAX) and thermal resistance, θJA. The derating curve in Figure 1 allows the designer to see the effect of rising ambient temperature on the maximum power dissipation. LXBST trace >80mil; Maximum Power Dissipation (W)1 P D(MAX) = (125°C − 25°C) / (28°C/W) = 3.57W for WQFN-24L 4x4 package VBAT trace >80mil; VMID trace >40mil; USBOUT1 trace >80mil; The switching node area connected to LX and inductor should be minimized for lower EMI. Connect the GND pin, PGNDBST pin and Exposed Pad together to a strong ground plane for maximum thermal dissipation and noise protection. Directly connect the output capacitors to the feedback network of each channel to avoid bouncing caused by parasitic resistance and inductance from the PCB trace. 4.0 Four-Layer PCB 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0 25 50 75 100 125 Ambient Temperature (°C) Figure 1. Derating Curve of Maximum Power Dissipation Copyright © 2014 Richtek Technology Corporation. All rights reserved. www.richtek.com 14 is a registered trademark of Richtek Technology Corporation. DS9483-01 September 2014 RT9483 LX should be connected to Inductor by wide and short trace, keep sensitive compontents away from this trace GND CBAT VBAT VMID Input capacitors must be placed as close as possible to the Input pins. GND CVMID GND C1 VBUS PGNDBST LXBST LXBST VMID 24 L1 PGNDBST VBUS CIN 23 22 21 20 19 COUT1 VBAT 1 18 USBOUT1 TS 2 17 USBOUT1 RNTC VBAT D1 D2 D3 D4 VMID 16 SWIN LED1 3 LED2 4 15 NC LED3 5 14 LED4 6 13 TP2 GND USBOUT1 Output capacitors must be placed as close as possible to the Output pins. NC 10 11 12 TORCH BUTTON TP1 9 NC NC 8 GND R3 7 R2 R1 D6 GND VMID GND Connect GND Pin and PGND Pin to Exposed Pad. Connect the Exposed Pad to a ground plane. Figure 2. PCB Layout Guide Copyright © 2014 Richtek Technology Corporation. All rights reserved. DS9483-01 September 2014 is a registered trademark of Richtek Technology Corporation. www.richtek.com 15 RT9483 Outline Dimension D2 D SEE DETAIL A L 1 E E2 e b A3 Symbol D2 E2 1 2 2 DETAIL A Pin #1 ID and Tie Bar Mark Options A A1 1 Note : The configuration of the Pin #1 identifier is optional, but must be located within the zone indicated. 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 0.180 0.300 0.007 0.012 D 3.950 4.050 0.156 0.159 Option 1 2.400 2.500 0.094 0.098 Option 2 2.650 2.750 0.104 0.108 E 3.950 4.050 0.156 0.159 Option 1 2.400 2.500 0.094 0.098 Option 2 2.650 2.750 0.104 0.108 e L 0.500 0.350 0.020 0.450 0.014 0.018 W-Type 24L QFN 4x4 Package 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 furnished 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 infringements 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 Richtek or its subsidiaries. www.richtek.com 16 DS9483-01 September 2014