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Technical content
Features
4.5V to 19V Input Voltage Range Adjustable Output Range, 0.6V Reference with 1% Accuracy Over-Temperature Protection FCOTTM (Flexible Constant On Time) Control Integrated 5V LDO@100mA for DrMOS module Support Pre-Biased Output Programmable Soft-Start Soft-Off through VOUT Discharge Programmable Switching Frequency Programmable Over Current Limit Power Good Indication OVP, UVP, UVLO Protection
Applications
High Current Distributed Power Systems Datacom and Telecom Systems Industrial Power Supplies General Description The RT2702 is a high-efficiency and high-current synchronous buck controller designed to drive a DrMOS module. A COT (Constant-On-Time) PWM controller and PWM signal for DrMOS are integrated so that the external circuit is easily designed and the component count is reduced. The RT2702 adopts FCOT control technology that responds instantly to input voltage change. Besides, the RT2702 includes a 5V (VDRV) linear regulator, which can provide 5V voltage and supply up to 100mA for DrMOS. The RT2702 supports two modes transition function with various operating states, which include audio skipping mode (ASM) and forced-CCM mode (FCCM). Other features include power good indication, external soft- start setting, soft-off discharge function, precise DCR sense, enable/disable control, over-voltage protection (OVP), under-voltage protection (UVP), current Limit, thermal shutdown into the WQFN-16L 3x3 package. 8H=YM DNN 8H= : Product Code YMDNN : Date Code Marking Information
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. Package Type QW : WQFN-16L 3x3 (W-Type) Lead Plating System G : Green (Halogen Free and Pb Free) RT2702 Pin Configuration (TOP VIEW) WQFN-16L 3x3 THWN DISB MODE PWM EN POK SS ILIM CSP FB CSN RGND VDRV PHASE TON VIN 13141516 8765 GND
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Functional Pin Description Pin No Pin Name Pin Function 1 MODE Operation mode detection input. 2 PWM Logic gate driver. This pin provides PWM signal for the gate drive. 3 DISB External driver enable. Enable external driver when DISB is high, and disable external driver when DISB is low. 4 THWN Thermal shutdown detection input. DISB goes low when THWN is less than trip level. 5 CSP Non-inverting input of current sense amplifier.
6 CSN
Inverting input of current sense amplifier. Connect a R CS from this pin to the current sensing R/C network for adjusting the over current trip threshold. VOUT is also discharged by this pin when system is shut down or any protection is toggled. Resistance of the discharge switch is around 30. 7 FB Feedback pin. This pin is the negative input node of the PWM comparator. 8 RGND Remote ground sense. This pin is intended to connect to the negative side of the load for remote sensing. 9 SS External soft-start pin. Achieve programmable soft-start time function, also have a default internal soft-start time 3ms for minimum soft-start time. DO NOT force this pin lower than 1.2V, otherwise soft-start procedure won't be finished. Refer to “Application Information” for further description. 10 ILIM The 1.2V buffered output for current limit adjustment. Connect a R ILIM between this pin and GND to set the over-current threshold corresponding to RCS. 11 POK Open drain power good indicator. High impedance indicates power is good. 12 EN Enable control input. The device enters its 20A supply current shutdown mode if EN is less than the EN input falling edge trip level and does not restart until EN is greater than the EN input rising edge trip level. Connect EN to VIN for automatically startup. EN can be connected to VIN through a resistive voltage divider to implement a programmable under-voltage lockout.
13 TON
On-time/switching frequency adjustment input. Connect a resistor to VIN for adjusting switching frequency. And connect an another 100pF ceramic capacitor between TON and ground is optional for noise immunity enhancement. 14 VIN Power supply input. 15 PHASE Switching node Input for zero current detection. Also provide V OUT information through PHASE pin to on-time generation circuit. 16 VDRV Output bypass for the 5V regulator. Connect a low-ESR bypass ceramic capacitor of 4.7F from this pin to GND. 17 (Exposed Pad) GND Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum thermal dissipation.
DS2702-00 October 2016 www.richtek.com ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Functional Block Diagram Mode Select LDO VREF 0.6V Soft-Start Control Current Limit Power-on Reset Driver Logic Enable Logic Over- Temperature Protection TON Gen. MODE PWM CSP TON POK ILIM CSN FB GND UVLO 112.5% VREF 87.5% VREF Control & Protection Logic VIN ZCD OVP UVP Soft-off EN To Power On Reset To Driver Logic To Soft-Start Control VDRV SS RGND Discharge VSEN CSN PHASE Current Limit Setting 1.2V VILIM /R ILIM DISB THWN 150 C
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Operation The RT2702 includes a constant on-time synchronous step-down controller and a linear regulator. Buck Controller In normal operation, the high-side N-MOSFET of DrMOS is turned on when the VFB is lower than VREF, and is turned off after the internal one-shot timer expires. While the high-side N-MOSFET of DrMOS is turned off, the low-side N-MOSFET of that is turned on to conduct the inductor current until next cycle begins. Soft-Start For internal soft-start function, an internal current source charges an internal capacitor to build the soft-start ramp voltage. The output voltage will track the internal ramp voltage during soft-start interval. For external soft-start function, an additional capacitor, connected between SS pin and GND, will be charged by a current source and determines the soft-start time. The RT2702 will track the slower one soft-start ramp during soft-start process. POK The power ok is the output of open-drain buffer. When the soft-start process is finished, this pin becomes high impedance. Current Limit The current limit circuit employs a unique “valley” current sensing algorithm. If V CSP is higher than VCSN, the PWM is not allowed to initiate a new cycle. Thus, the current to the load exceeds the average output inductor current, eventually, output drops lower than the under-voltage protection threshold, inducing IC shutdown. Over-Voltage Protection (OVP) & Under-Voltage Protection (UVP) The output voltage is continuously monitored for over- voltage and under-voltage conditions. When the voltage of FB pin exceeds over-voltage threshold (112.5% of V REF), the PWM signal goes low. When it is less than 87.5% of V REF, under-voltage protection is triggered and then the DISB signal will be pulled low to disable DrMOS. The controller begins hiccup procedure and restart up after 20ms. VDRV Internal LDO turns on When the VIN and EN voltage exceed the POR rising threshold, respectively. Provide 5V supply voltage at VDRV pin.
DS2702-00 October 2016 www.richtek.com ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Recommended Operating Conditions (Note 4) Absolute Maximum Ratings (Note 1) PHASE to GND Power Dissipation, PD @ TA = 25°C Package Thermal Resistance (Note 2) ESD Susceptibility (Note 3)
Electrical Characteristics
(VIN = VEN = 6V, RTON = 390kΩ, TA = −40°C to 105°C , unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Supply Operating Conditions VIN Voltage Range V IN 4.5 -- 19 V VIN Supply Current VIN Operating Current I Q V IN = 6V, EN = high, VFB = 0.6V -- -- 1 mA VIN Shutdown Current I SD V IN = 6V, EN = low -- -- 40 A VIN Supply Voltage VIN UVLO Start Threshold V IN_UVLO Rising -- -- 4.5 V VIN UVLO Hysteresis V IN,UVLO_HYS -- 500 -- mV VDRV Regulator VDRV Output Voltage V DRV V IN > 5.5V, IVDRV < 35mA 4.8 5 5.3 V VDRV Output Voltage 4.5V < V IN < 5.5V, IVDRV < 25mA 4 5 5.3 V VDRV Output Current I DRV V DRV = 4V 100 -- -- mA
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Parameter Symbol Test Conditions Min Typ Max Unit VREF Internal Reference Voltage V REF T A = 25°C 0.597 0.6 0.603 V Output Voltage Accuracy VFB VFB to RGND excluding external resistor divider tolerance -1 -- 1 % Switching Frequency Control Switching Frequency f SW VIN = 6V, VOUT = 1V, RTON = 390k -- 500 -- kHz Minimum Turn Off Time (LG on) t OFF_MIN V FB = 0.55V -- 275 400 ns Minimum Skip Mode Frequency V FB > 0.6V 20 -- -- kHz Soft- Start Soft Start Setting Current I SS 8 10 12 A Internal Soft Start t SS_INT VSS = VDRV, 10% VREF to 90% VREF 1 3 5 ms Soft- Off Soft Off Bleeding Resistor R DIS -- 30 -- Over Current Protection VILIM Output Voltage V ILIM 1.188 1.2 1.212 V Over Current Threshold Offset V OC_OFS VCSP VCSN = VILIM x (RCS/RILIM) = 50mV 3 -- 3 mV Zero Current Threshold V ZC GND – PHASE 6 -- 2 mV Protection and PGOOD POK Output Voltage Logic low, sinking 4 mA -- -- 0.4 V OVP Threshold V OVP V FB rising 108.5 112.5 116.5 % UVP Threshold V UVP V FB falling 83.5 87.5 91.5 % Power Good Low Delay t POK_DLY -- 10 -- s PWM Driving Capability PWM Source Resistor R PW M_SRC V DRV to PWM -- -- 35 PWM Sink Resistor R PW M_SK PWM to GND -- -- 15 Logic I/O EN Input Voltage VEN_OFF Controller OFF -- 0.925 -- V VEN_ON Controller ON -- 1 -- V MODE Input Voltage VMODE_L ASM (Audio Skipping Mode) -- -- 0.4 V VMODE_H FCCM 1.2 -- -- V THWN Input Voltage THWN_LV PWM float, VDRV remains ON -- -- 0.4 V THWN_HV Normal operation 2 -- -- V DISB Output Resistor DISB_SRCV VDRV to DISB -- -- 55 DISB_SKV DISB to GND -- -- 30
DS2702-00 October 2016 www.richtek.com ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Parameter Symbol Test Conditions Min Typ Max Unit Thermal Shutdown Thermal Shutdown T SD -- 150 -- °C Thermal Shutdown Hysteresis TSD -- 25 -- °C 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 under natural convection (still air) at T A = 25 °C with the component mounted on a high effective- thermal-conductivity four-layer test board on a JEDEC 51-7 thermal measurement standard. 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.
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Typical Application Circuit TON VIN POK VDRV ILIM MODE SS 17 (Exposed Pad) EN PHASE PWM CSP CSN FB RGND RT2702 4.7µF 100k VDRV VCIN VIN PWM PHASE BOOT VSWH DrM OS 1µF
0 VDRV
C11* R11* 0.21µH R12 1.6k C12 470nF R13 180 VOUT 1VC13 1.2mF R14 20k R15 30k C14* VIN 4.5V to 19V 10µF 100nF 390k 100pF On Off 24k C4* GND SMODSMOD DISB THWNTHWN DISB * : Optional 22µF 22µF 100nF C15 22µF C16 22µF PHASE PHASE
DS2702-00 October 2016 www.richtek.com ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Typical Operating Characteristics Efficiency vs. Output Current 100 0 5 10 15 20 25 Output Current (A) Efficiency (%) Switching Frequency vs. Output Current 400 420 440 460 480 500 520 540 560 0.01 0.1 1 10 100 Output Current (A) Switching Frequency (kHz) 1 Switching Frequency vs. Input Voltage 450 460 470 480 490 500 510 520 530 540 550 4 6 8 1 01 21 41 61 82 0 Input Voltage (V) Switching Frequency (kHz) 1 VOUT vs. ILOAD 1.005 1.006 1.007 1.008 1.009 1.01 1.011 1.012 1.013 1.014 1.015 0 5 10 15 20 25 ILOAD (A) VOUT (V) VDRV vs. IDRV 5.020 5.025 5.030 5.035 5.040 5.045 5.050 5.055 5.060 0 1 02 03 04 05 06 07 08 09 0 1 0 0 IDRV (mA) VDRV (V) VIN = 19V VIN = 4.5V VIN = 5.5V VIN = 12V VEN = VIN, VOUT = 1V, fSW = 500kHz, FCCM VEN = VIN, VOUT = 1V, fSW = 500kHz, FCCM VIN = 19V VIN = 4.5V VIN = 5.5V VIN = 12V VEN = 12V, VOUT = 1V, IOUT = 20A, fSW = 500kHz, FCCM VEN = VIN, VOUT = 1V, fSW = 500kHz, FCCM VIN = 4.5V VIN = 5.5V VIN = 12V VIN = 19V VEN = VIN = 12V Quiescent Current vs. Input Voltage 700 800 900 1000 1100 1200 1300 1400 1500 1600 4 6 8 1 01 21 41 61 82 0 Input Voltage (V) Quiescent Current (uA ) VEN = V IN, VMODE = 5V, VFB = 0.6V
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Shutdown Current vs. Input Voltage 4 6 8 1 01 21 41 61 82 0 Input Voltage (V) Shutdown Current (μA) 1 Switching Frequency vs. Temperature 400 420 440 460 480 500 520 540 560 -40 -20 0 20 40 60 80 100 120 140 Temperature (°C) Switching Frequency (kHz) 1 EN High Level Threshold vs. Temperature 0.90 0.93 0.95 0.98 1.00 1.03 1.05 -40 -20 0 20 40 60 80 100 120 140 Temperature (°C) EN High Level Threshold (V) 1 EN Low Level Threshold vs. Temperature 0.85 0.88 0.90 0.93 0.95 0.98 1.00 -40 -20 0 20 40 60 80 100 120 140 Temperature (°C) EN Low Level Threshold (V ) VEN = GND, VMODE = 5V Output Voltage vs. Temperature 1.000 1.003 1.005 1.008 1.010 1.013 1.015 1.018 1.020 -40 -20 0 20 40 60 80 100 120 140 Temperature (°C) Output Voltage (V) VEN = VIN, VOUT = 1V, No Load, fSW = 500kHz, FCCM VEN = VIN, VOUT = 1V, No Load, fSW = 500kHz, FCCM VIN = 12V VIN = 12V Power On from EN Time (2ms/Div) VEN (10V/Div) VIN = VEN = 12V, VOUT = 1V, IOUT = 20A VOUT (1V/Div) VDRV (5V/Div) VPOK (5V/Div) VIN = 4.5V VIN = 12V VIN = 4.5V VIN = 12V
DS2702-00 October 2016 www.richtek.com ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Power Off from EN Time (100ms/Div) VEN (10V/Div) VIN = VEN = 12V, VOUT = 1V, IOUT = 10mA VOUT (1V/Div) VDRV (5V/Div) VPOK (5V/Div) Load Transient Response Time (40 μs/Div) IOUT (20A/Div) VOUT (100mV/Div) VIN = VEN = 12V, VOUT = 1V, IOUT = 0A to 20A PWM (5V/Div) OVP VOUT (500mV/Div) VPOK (5V/Div) Time (10 μs/Div) PWM (5V/Div) VEN = VIN = 12V, VOUT = 1V, No Load UVP Time (20 μs/Div) VOUT (500mV/Div) VPOK (5V/Div) PWM (5V/Div) VEN = VIN = 12V, VOUT = 1V Over Current Limit Time (10 μs/Div) VOUT (500mV/Div) VPOK (5V/Div) PWM (5V/Div) IL (10A/Div) VEN = VIN = 12V, VOUT = 1V VOUT IL VPOK PWM
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation.
Application Information
The RT2702 is a high-efficiency and high-current synchronous buck controller designed to drive a DrMOS module. A COT (Constant-On-Time) PWM controller and PWM signal for DrMOS are integrated so that the external circuit is easily designed and the component count is reduced. The RT2702 adopts FCOT control technology that responds instantly to input voltage change. Besides, the RT2702 includes a 5V (VDRV) linear regulator, which can provide 5V voltage and at least 100mA current loading. The topology circumvents the poor load transient timing problems of fixed-frequency current mode PWMs while avoiding the problems caused by widely varying switching frequency in conventional constant-on-time and constant- off-time PWM schemes. The IC supports two modes transition function with various operating states, which include audio skipping mode (ASM) and forced-CCM mode (FCCM). These different operating eliminates audio-frequency modulation and states make the system efficiency as high as possible. The device can operate at wide input voltage range from 4.5 V to 19V. It is capable of producing an output voltage as low as 0.6V. Other features include power good indication, external soft start setting, soft-off discharge function, OVP, UVP, Current Limit, precise DCR sense, and enable/disable control. PWM Operation The RT2702 integrates a Constant-On-Time PWM controller, and the controller provides the PWM signal which relies on the FB voltage comparing with internal reference voltage as shown in Figure 1. Refer to the function block diagram of the RT2702, the synchronous high side MOSFET of DrMOS will be turned on at the beginning of each cycle. After the internal one shot timer expires, the MOSFET will be turned off. The pulse width of this one shot is determined by the converter’s input voltage and the output voltage to keep the frequency constant in a specific input voltage range. Another one shot sets a minimum off-time (275ns typ.). The on-time one shot will be triggered if the PWM comparator output is high, the low side switch current is below the current limit threshold and the minimum off-time one shot has timed out. Figure 1. Constant On-Time PWM Control and CTON without a clock generator. 1.2V, controller enters forced-CCM.
©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. initialization and soft-start procedure. until the protections are clean. high-state, low-state, and back to HiZ-state. to keep the switching frequency fairly constant. Figure 2. Soft-Start Sequence
©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. will begin ramping up after 3ms to 4ms from EN high. is designed as a typical value 3ms from 10% to 90% VREF. system shuts down or re-starts up. placed between SS pin and GND. Figure 3. Soft-Start Control Block. external ramp is lower than internal ramp(VExt. < VInt.). is finished and has no UVP nor OVP. of DCR circuitry to determine the turn-on timing of PWM. int. and ext. SSOK are high.
©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Figure 4. “Valley” Current Limit
1.2 RR IR
Figure 5. External Current Limit Setting but also effective way to compensate temperature variation. Figure 6. Thermal Compensation Method
www.richtek.com DS2702-00 October 2016 ©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. Let EQU S P NTCR = R ( R / / R) RRL EQU SEN = CSENRR RL,DCR EQU SEN According to current sense network and temperate, the corresponding equation is represented as follows : Next, let Lm = RCL,DCR SEN Then RR RRNTC P NTC PmR R = R RSEN S SEN SRR RRN T CP N T CP Step 1 : Given the two system temperature TL and TH at which are compensated. Step 2 : Two equations can be listed as R( T ) RNTC L Pm(T ) R RLS E N S R( T ) RNTC L P R( T ) RNTC L P= R RSEN S R( T ) RNTC L P R( T ) RNTC H Pm(T ) R RH SEN S R( T ) RNTC H P R( T ) RNTC H P= R RSEN S R( T ) RNTC H P Step 3 : Since RP is usually set equal to RNTC(25°C), two unknowns, RSEN and R S, can be calculated using two equations. Output Over-Voltage Protection (OVP) The voltage on the FB pin is monitored for over-voltage protection. When the FB voltage exceeds 12.5% of its set voltage threshold, over-voltage protection is triggered, then the signal of POK and PWM go low. This behavior should command DrMOS to discharge the output capacitor. A 10μs delay is applied to OVP detection circuit to prevent false trigger. Besides, anti-overshoot(AOS) would be triggered when V FB is above 642mV (V REF + 42mV) and then PWM becomes tri-state. Thus more power, which is stored in inductor, would be eliminated by the body diode of LSMOS in DrMOS, and prevents V OUT from having too much overshoot. If inductor has too much power stored in itself, FB1OUT REF FB2 RVV1 R where the VREF is 0.6V (typical), and the recommended output voltage range is between 0.6V and 3V. then AOS won't be able to prevent system from triggering OVP. In this case, OVP would over-write AOS behavior, makes PWM go low and intends to discharge V OUT with negative current on inductor. Output Under-Voltage Protection (UVP) The FB voltage is monitored for under voltage protection. When the FB voltage is less than 12.5% of its set voltage threshold during normal operation, under-voltage protection is triggered, then the signal of POK and DISB to be low. This behavior should turn off DrMOS. When UVP is triggered, the controller begins hiccup procedure and re- boost after 20ms. A 10μs delay is applied to UVP detection circuit to prevent false trigger. Over-Thermal Protection (OTP) The RT2702 features an over-thermal protection circuitry to prevent damage from excessive heat dissipation. The OTP function occurs when the die temperature exceeds 150°C, then DISB goes low and turns off internal linear regulator. Once the junction temperature is cooled down by approximately 25°C, the RT2702 will reboost from the beginning. Thermal Shutdown Detection (THWN) The RT2702 has a thermal shutdown detection input THWN pin for external driver DrMOS. The RT2702 will pull low DISB if the voltage of thermal warning flag is lower than 0.4V. Output Voltage Setting The output voltage waveform is shown as Figure 7, which can be adjusted from 0.6V to 3.3V by setting the feedback resistors, R FB1 and RFB2 (see Figure 8). Choose RFB2 to be approximately 30k and solve for RFB1 using the equation below :
©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. where IPEAK is the peak inductor current. on the maximum power dissipation. Figure 9. Derating Curve of Maximum Power Dissipation starting a layout for the RT2702. recommended. Place these capacitors close to the IC. to high voltage switching node. short as possible to reduce stray inductance. power traces and components. the current limit resistor located at the device. handling (including the chip power ground connections). capacitor(s) are recommended.
©Copyright 2016 Richtek Technology Corporation. All rights reserved. is a registered trademark of Ric htek Technology Corporation. with 10 to 15 mil wide traces. The rule of thumb of the gap between is 1~2xtrace width. Clearance from other aggressor is 3xtrace width. Figure 10. PCB Layout Guide
www.richtek.com DS2702-00 October 2016 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. Outline Dimension A D E L be SEE DETAIL A 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 0.180 0.300 0.007 0.012 D 2.950 3.050 0.116 0.120 D2 1.300 1.750 0.051 0.069 E 2.950 3.050 0.116 0.120 E2 1.300 1.750 0.051 0.069 e 0.500 0.020 L 0.350 0.450 0.014 0.018 W-Type 16L QFN 3x3 Package 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 2 2