JWH5086QFNAG#TRPBF

JWH5086A 16V/16A Synchronous Step-Down Converter ESCRIPTION FEATURES The JWH5086A is a monolithic buck switching regulator based on I2 architecture for fast transient response. Operating with an input range of 2.7V~16V, JWH5086A delivers 16A of continuous output current with two integrated N-Channel MOSFETs. The internal synchronous power switches provide high efficiency without the use of an external Schottky diode. The operation frequency is set easily to 700 kHz, 800 kHz, or 1000 kHz with the MODE configuration, allowing the JWH5086A frequency to remain constant regardless of the input and output voltages.  2.7V to 16V Operating Input Range with External 3.3V VCC Bias 4V to 16V Operating Input Range with Internal Bias or External 3.3V VCC Bias 16A output current Differential Output Voltage Remote Sense Programmable Accurate Current Limit Level ±0.5% Reference Voltage over 0℃ to +70℃ Junction Temperature Range FCCM Operation Mode Power Good Indicator Programmable Soft-Start Time Selectable Switching Frequency from 700kHz, 800kHz, and 1000kHz Output Discharge Function Non-Latch OCP, UVP, OVP, UVLO Thermal Protection Available in QFN3X4-21 Package          JWH5086A guarantees robustness with output short protection, over-voltage protection, thermal protection and under voltage protection.    JWH5086A is available in QFN3×4-21 package, which provides a compact solution with minimal external components.  APPLICATIONS Company’s Logo is Protected, “JW” and “JOULWATT” are Registered Telecom and Networking Systems Server, Cloud-Computing, Storage Base Stations General Purpose Point-of-Load  Trademarks of Joulwatt Technology Co., Ltd.    TYPICAL APPLICATION CB S T 100nF VO U T VIN 4V~16V L 0 .2 2 u H V IN SW PG EN O N /O F F MODE CI N 10uFX3 BST JWH5086A RP G 10k C f f (o p t.) R1 2k FB CS 1uF R2 CO U T 47uFX5 RGND RM O D E 6 0 .4 k 0 .6 V ~ 5 . 5 V RC S 6 .9 8 k VCC CV C C 1u F PGND SS AGND CS S 100nF JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 1 / 20 JWH5086A JoulWatt ORDER INFORMATION DEVICE1) PACKAGE JWH5086AQFNAG#TR QFN3X4-21 TOP MARKING2) JH5086A YW□□□□□ ENVIRONMENTAL3) Green Notes： JW # TR 1) J 2 ) L in e 1 : T a p e a n d R e e l ( If T R is n o t s h o w n , it m e a n s T u b e ) Package Code P a rt N o . YW Lot num ber P ro d u ct co d e L in e 2 : W eek code J o u lw a t t L O G O Year code 3 ) A ll J o u lW a t t p r o d u c t s a r e p a c k a g e d w it h P b - f r e e a n d H a lo g e n - f r e e m a t e r ia ls a n d c o m p lia n t t o R o H S s t a n d a r d s . PIN CONFIGURATION TOP VIEW V IN SW 21 20 BST 1 AGND 2 18 PGND CS 3 17 PGND MODE 4 16 PGND SS 5 15 PGND RGND 6 14 PGND FB 7 13 PGND EN 8 12 PGND PG 9 11 PGND 10 19 VCC V IN ABSOLUTE MAXIMUM RATING1） VIN Pin…….......................................................................................................................... -0.3V to 18V SW Pin.................................................................................... -0.3V (-5V for 25ns) to 18V (25V for 25ns) VIN-SW.................................................................................-0.3V (-5V for 25ns) to 18.3V (25V for 25ns) BST-SW ............................................................................................................ -0.3V to 4V (5V for 25ns) VCC Pin ................................................................................................................................. -0.3V to 4V All other Pins .......................................................................................................................... -0.3V to 4V Junction Temperature 2) ..............................................................................................................150ºC Lead Temperature ..........................................................................................................................260ºC Storage Temperature………………………………………………………………………...-65 ºC to +150 ºC ESD Susceptibility (Human Body Model) .........................................................................................±2kV Charged device model (CDM), per JEDEC specification JESD22- V C101.................................... ±500V JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 2 / 20 JWH5086A JoulWatt RECOMMENDED OPERATING CONDITIONS3） Input Voltage VIN ...................................................................................................................... 4V to 16V Output Voltage VOUT ............................................................................................................. 0.6V to 5.5V External VCC Bias VCC_EXT ......................................................................................................Up to 3.6V Maximum Internal VCC Output Current IVCC_MAX............................................................................150mA Maximum Output Current IOUT_MAX ..................................................................................................... 16A Maximum Output Current Limit IOC_MAX .............................................................................................. 20A Maximum Peak Inductor Current Limit IL_Peak .....................................................................................30A Operation Junction Temperature Tj.. ................................................................................ -40°C to 125°C THERMAL PERFORMANCE4） θJB 5) θJc_TOP 5) QFN3X4-21............................................................................................................................8....18ºC/W Note： 1) 3) 4) Exceeding these ratings may damage the device. These stress ratings do not imply function operation of the device at any other conditions beyond those indicated under RECOMMENDED OPERATING CONDITIONS. The JWH5086A includes thermal protection that is intended to protect the device in overload conditions. Continuous operation over the specified absolute maximum operating junction temperature may damage the device. The device is not guaranteed to function outside of its operating conditions. Measured on JESD51-7, 4-layer PCB. 5) θ Thermal resistance from junction to board around PGND pin soldering point. 2) JB θ Jc_TOP Thermal resistance from junction to top of package. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 3 / 20 JWH5086A JoulWatt ELECTRICAL CHARACTERISTICS VIN=12V, TJ=-40℃~125℃，Unless otherwise stated. Item Symbol Conditions Min. Typ. Max. Unit VIN_HTH VIN rising, VCC=3.3V 2.1 2.4 2.7 V VIN_LTH VIN falling, VCC=3.3V 1.55 1.85 2.15 V Shutdown Current ISD VEN =0 0.5 5 μA Supply Current IQ VEN=2V, VFB=0.7V 550 800 μA Enable Input Rising Threshold VEN_HTH 1.22 1.27 V Enable Hysteresis VEN_TH_HYS Enable Input Current IEN Feedback Voltage VREF Feedback Current IFB Top Switch Resistance VIN Under Voltage Lock-out Threshold 1.17 VEN=2V 200 mV 0 μA TJ=-40℃ to 125℃ 594 600 606 mV TJ= 0℃ to 70℃ 597 600 603 mV 10 100 nA RDS(ON)T 8.9 13.8 mΩ Bottom Switch Resistance RDS(ON)B 2.6 4.8 mΩ Top Switch Leakage Current ILEAK_TOP VIN=16V, VSW=0V 10 μA Bottom Switch Leakage Current ILEAK_BOT VIN=16V, VSW=16V 10 μA Current Limit Threshold VLIM ICS to IOUT Ratio ICS/IOUT Bottom Switch Negative Current Limit ILIM_NEG Minimum On Time6) TON_MIN Minimum Off Time6) TOFF_MIN Switching Frequency FSW VFB=0.6V RCS =6K 1.15 1.2 1.25 V 8 9 11 μA/A -21 -16 -12 A 50 ns 100 180 ns MODE=GND 560 660 760 kHz MODE=30.1K 640 750 860 kHz MODE=60.4K 860 970 1080 kHz 110 200 Ω Discharge FET Ron RDIS Soft-Start Charge Current ISS_CHAR VSS=0V Soft-Start Pull Down Current ISS_DISCHAR VSS=1V 0.4 0.55 0.7 mA Soft-Start Time6) TSS CSS=1nF 0.5 1 1.5 ms VCC_HTH VCC rising 2.65 2.8 2.95 V VCC_LTH VCC falling 2.35 2.5 2.65 V 3.1 3.2 3.35 V VCC Under-voltage Lockout Threshold VCC Regulator VCC VCC Load Regulation 42 ICC=100mA Power Good High Threshold PG_HTH Power Good Low Threshold PG_LTH μA 0.5 % VFB from low to high 89.5% 92.5% 95.5% VREF VFB from high to low 102% 105% 108% VREF VFB from low to high 113% 117% 121% VREF VFB from high to low 77% 80% 83% VREF JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 4 / 20 JWH5086A JoulWatt VIN=12V, TJ=-40℃~125℃，Unless otherwise stated. Item Symbol Conditions Min. Typ. Max. Unit 0.7 1.1 1.5 ms Power Good Delay Time PG_DLY VPG from low to high Power Good Sink Current IPG VPG =0.5V Power Good Leakage Current ILEAK_PG VPG=3.3V 3 mA 3.5 5 μA 520 800 mV 620 900 mV VIN=0V, Pull PG up VOL_100 to 3.3V through a 100kΩ resistor Power Good Low-level Output Voltage VIN=0V, Pull PG up VOL_10 to 3.3V through a 10kΩ resistor Output Over-voltage Threshold VFB Rising 113% 117% 121% VREF Output Under-voltage Threshold VFB Falling 77% 80% 83% VREF Output UVP Delay TDLY_UVP 1.7 μs UVP/OCP Hiccup OFF Time THICCUP_OFF 12 ms Thermal Shutdown6) TTSD 160 °C TTSD_HYST 30 °C TDLY_POWERON 95 μs Thermal Shutdown Hysteresis6) Power On Delay Time Note： 6) Guaranteed by design. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 5 / 20 JWH5086A JoulWatt PIN DESCRIPTION Pin Name 1 BST 2 AGND 3 CS 4 MODE 5 SS 6 RGND Description Connect a 0.1uF capacitor between BST and SW pin to supply current for the top switch driver. Analog ground pin. Select AGND as the control circuit reference point. Current limit. Connect a resistor to AGND to set the current limit trip point. Frequency selection. Program MODE to select the operating switching frequency. Soft-start time setting pin. The soft-start time is determined by the capacitance between SS pin and AGND. Differential remote sense negative input. Connect this pin directly to the negative side of the voltage sense point. Short to GND if remote sense is not used. Feedback (Differential remote sense positive input). An external resistor divider from the 7 FB output to RGND (tapped to FB) sets the output voltage. It is recommended to place the resistor divider as close to FB as possible. Vias should be avoided on the FB traces. 8 EN 9 PG 10, 21 VIN 11-18 GND 19 VCC 20 SW Enable control pin. Pull this pin high to turn on the regulator. Do not leave this pin floating. Power good monitor output. Open drain output when the output voltage is within 92.5% to 117% of internal reference voltage. Input voltage pin. VIN supplies power to the IC. Connect a 2.7V to 16V supply to VIN and bypass VIN to GND with a suitably large capacitor to eliminate noise on the input to the IC. Power ground pin Internal 3.2V LDO Output. Power supply for internal analog circuits and driving circuit. Decouple this pin to ground with a minimum 1uF ceramic capacitor. SW is the switching node that supplies power to the output. Connect the output LC filter from SW to the output load. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 6 / 20 JWH5086A JoulWatt BLOCK DIAGRAM V IN + - PG + C u rre n t S ensor - 0 .5 5 5 V 0 .7 0 2 V + VCC U V L O /O T P BST - FB RGND SS + EA SW R e fe re n c e C u r r e n t R ip p le A d ju s tm e n t L o g ic C o n tro l MODE S e le c tio n MODE V a lle y C u r r e n t L im it & Z C D CS Current Sensor + AGND V IN PGND 3 .2 V L D O VCC + 1 .2 2 V - EN JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 7 / 20 JWH5086A JoulWatt TYPICAL PERFORMANCE CHARACTERISTICS VIN = 12V, VOUT = 1.2V, L = 0.22μH, COUT = 47μF×5, FSW = 700kHz, TA = +25°C, unless otherwise noted. Steady State Test Startup through Enable Shutdown through Enable VIN=12V, VOUT=1.2V IOUT=16A VIN=12V, VOUT=1.2V IOUT=16A VIN=12V, VOUT=1.2V IOUT=16A EN 2V/div EN 2V/div VOUT(AC) 20mV/div SW 10V/div IL 20A/div VOUT 1V/div VOUT 1V/div SW 10V/div SW 10V/div IL 20A/div IL 20A/div 4ms/div 2us/div 4ms/div Steady State Test Short Circuit Protection Short Circuit Recovery VIN=12V, VOUT=1.2V IOUT=0A VIN=12V, VOUT=1.2V IOUT=0A→Short VIN=12V, VOUT=1.2V IOUT=Short→0A VOUT(AC) 20mV/div VOUT 1V/div VOUT 1V/div IL 20A/div IL 20A/div SW 10V/div IL 20A/div 2us/div 10ms/div 10ms/div Short Circuit Protection Short Circuit Recovery Load Transient VIN=12V, VOUT=1.2V IOUT=16A→Short VIN=12V, VOUT=1.2V IOUT=Short→16A VIN=12V, VOUT=1.2V IOUT=1.6A~16A VOUT 1V/div VOUT 1V/div IL 20A/div IL 20A/div 10ms/div VOUT(AC) 50mV/div IL 20A/div 10ms/div JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 100us/div 8 / 20 JWH5086A JoulWatt TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs. Load Current Efficiency vs. Load Current (VOUT=1.2V, L=0.22uH, FSW=700kHz) (VOUT=1.8V, L=0.22uH, FSW=1MHz) Efficiency vs. Load Current Frequency vs. Load Current (VOUT=3.3V, L=0.22uH, FSW=1MHz) (VIN=12V, VOUT=1.8V, L=0.22μH) Load Regulation FB Voltage Regulaion vs. Junction Temperature (VOUT=1.2V, L=0.22uH, FSW=700kHz) JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 9 / 20 JWH5086A JoulWatt FUNCTIONAL DESCRIPTION JWH5086A is a synchronous step-down regulator based on I2 control architecture. It regulates input voltages from 2.7V to 16V down to as low as 0.6V output voltage, and is capable of supplying up to 16A of load current. Power Switch Frequency Selection JWH5086A operates in forced continuous conduction mode (FCCM), and the switching frequency is fairly constant; hence the output ripple keeps almost the same throughout the whole load range. JWH5086A has three options for switching frequency selection. Selecting the switching frequency is done by choosing the resistance value of the resistor connected between MODE and AGND (See Table 1). Table 1 --- Frequency selection Switching Frequency7) GND 700kHz 30.1kΩ(±20%) to GND 800kHz 60.4kΩ(±20%) to GND 1000kHz Note： 7) The JWH5086A shuts down when voltage at EN pin is below 0.3V. The entire regulator is off and the supply current consumed by the JWH5086A drops below 5uA. VIN Under-Voltage Protection N-Channel MOSFET switches are integrated on the JWH5086A to down convert the input voltage to the regulated output voltage. Since the top MOSFET needs a gate voltage greater than the input voltage, a boost capacitor connected between BST and SW pins is required to drive the gate of the top switch. The boost capacitor is charged by the internal/external rail when SW is low. MODE Shut-Down Mode Refer to ELECTRICAL CHARACTERISTICS for more accurate switching frequency data. In addition to the enable function, the JWH5086A provides an Under Voltage Lock-out (UVLO) function that monitors the input voltage. To prevent operation without fully-enhanced internal MOSFET switches, this function inhibits switching when input voltage drops below the UVLO-falling threshold. The IC resumes switching when input voltage exceeds the UVLO-rising threshold. Enable and Protection Adjustable UVLO The JWH5086A is enabled when the VIN pin voltage rises above 2.4V and the EN pin voltage exceeds the enable threshold of 1.22V. The JWH5086A is disabled when the VIN pin voltage falls below 1.85V or when the EN pin voltage is below 1.02V. Do not leave this pin floating. If an application requires a higher VIN undervoltage lockout (UVLO) threshold, use a resistive divider connected between VIN and ground with the central tap connected to EN to adjust the input voltage UVLO. (Shown in Figure 1). So that when VIN rises to the pre-set value, VEN rises above 1.22V to enable the device and when VIN drops below the pre-set value, VEN drops below 1.02V to trigger input under voltage lockout protection. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 10 / 20 JWH5086A JoulWatt VIN The JWH5086A has a configured external soft start time and a constant internal soft start time, it will follow the slower one between them. Therefore, the minimum soft start time is about 1ms even a smaller capacitor is used. The soft start will not be ready until both the internal and external SS voltage exceeds 0.85V. V IN RUVLO_upper JW H 5086A EN RUVLO_lower GND Figure. 1 Adjustable UVLO The input voltage UVLO threshold (VUVLO) and hysteresis (VUVLO_HYS) can be calculated by the following equation. VUVLO  RUVLO_upper  RUVLO_lower  VEN_TH RUVLO_lower VUVLO_HYS  RUVLO_upper  RUVLO_lower  VEN_HYS RUVLO_lower where VEN_TH is enable shutdown threshold (1.22V typ.); VEN_HYS is enable shutdown hysteresis (200mV typ.). Soft Start Soft-start is designed in JWH5086A to prevent the converter output voltage from overshooting during startup and short-circuit recovery. An internal current source (ISS) of 42uA is designed to charge the external soft-start capacitor (CSS) and generates a soft-start (SS) voltage ramping up from 0V to 1.5V. When it is less than internal reference voltage (VREF, typ. 0.6V), SS voltage overrides VREF and the error amplifier uses SS voltage as the reference. When SS exceeds VREF, VREF regains control. The soft start time (10% to 90%) TSS can be calculated by the following equation. TSS ( ms)  CSS ( nF)  VREF ( V)  0.8 ISS ( A ) where CSS is the soft-start capacitance connected between SS pin and AGND pin. At power up, the soft start pin is discharged before MOSFETs switching to ensure a proper power up. Also, during normal operation, the JWH5086A will stop switching and the soft-start pin will be discharged, when the VIN UVLO is exceeded, EN pin pulled below 1.02V, or a thermal shutdown event occurs. Current Sense Protection (OCP) and Over-Current The JWH5086A features an on-die current sense and a programmable positive current limit threshold. The cycle-by-cycle current limit is activated when the JWH5086A is enabled. The SW valley current limit is proportional to ICS current, which is set by a resistor (RCS) from CS to AGND. The following equation calculates the current limit threshold setting from RCS: RCS ( )  VOCP   GCS  ILIM  VIN  VOUT   VOUT VIN  1   2  L  fSW where VOCP=1.2V, GCS = 9 μA/A, and ILIM = the desired output current limit. The OCP HICCUP is active 3ms after the JWH5086A is enabled, Once OCP HICCUP is active, if the JWH5086A detects over-current condition for consecutive 31 cycles, or if the FB drops below under-voltage protection (UVP) threshold, it enters HICCUP mode. In HICCUP mode, the JWH5086A latches off the high side MOSFET immediately, and latches off low side JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 11 / 20 JWH5086A JoulWatt MOSFET after ZCD is detected. Meanwhile, the SS capacitor is also discharged. After about 12ms, the JWH5086A will try to soft start automatically. If the over-current condition still holds after 3ms of running, the JWH5086A repeats this operation cycle until the over-current condition disappears, and the output voltage rises smoothly back to the regulation level. Negative Inductor Current limit When the low side MOSFET detects a -16A current, the part turns off the low side MOSFET to limit the negative current. Pre-Bias Start-Up The JWH5086A has been designed for a monotonic start-up into pre-biased loads. If the output is pre-biased to a certain voltage during start-up, the IC disables switching for both the high-side and low-side MOSFETs until the voltage on the SS capacitor exceeds the sensed output voltage at FB. Before SS voltage reaches pre-biased FB level, if the BST voltage (from BST to SW) is lower than 1.8V, the low-side MOSFET is turned on to allow the BST voltage to be charged through VCC. The low-side MOSFET is turned on for very narrow pulses, so the drop in pre-biased level is negligible. Output Voltage Discharge When the JWH5086A is disabled through EN, it enables the output voltage discharge mode. This causes both the high side MOSFET and the low side MOSFET to latch off. A discharge FET connected between SW and PGND is turned on to discharge the output voltage. The typical switch on resistance of this FET is about 110Ω. Once the FB voltage drops below 10%* VREF, the discharge FET is turned off. Output Over-voltage Protection The JWH5086A monitors the output voltage by connecting FB to the tap of the output voltage feedback resistor divider to detect an overvoltage condition. This provides autorecovery OVP mode. If the FB voltage is between 105% and 117% of REF voltage, the low side MOSFET remains on until it hits the low-side negative current limit (NOCP). Once it hits NOCP, the low side MOSFET is turned off and the high side MOSFET is turned on until the negative current reaches to zero. The JWH5086A keeps this operation to try to bring down the output voltage. If the FB voltage furtherly exceeds 117% of the REF voltage, it enters OVP mode. The high side MOSFET is turned off and the low side MOSFET remains on until it hits NOCP. Once it hits NOCP, the power MOSFETs stop switching. The power MOSFETs would not restart switching until the FB voltage drops below 105% of REF voltage. PGOOD goes low until the FB voltage drops below 105% of REF voltage. Power Good The JWH5086A has power-good (PG) output. The PG pin is the open drain of a MOSFET. Connect to VCC or another voltage source through a resistor. After applying the input voltage, the power MOSFETs start switching, PG is pulled to GND before SS is ready. After the FB voltage reaches 92.5% of the REF voltage and soft start is ready, PG is pulled high after a 1.1ms delay. When the FB voltage drops to 80% of the REF voltage, PG is pulled low within 1.7us deglitch time. When the FB voltage rises above 92.5% of the REF voltage, PG is pulled high again after a 1.1ms delay time. When the FB voltage exceeds 117% of the REF voltage, PG is pulled low within 1.7us deglitch time. When the FB voltage drops to 105% of the REF voltage, PG is pulled high again with 1.1ms deglitch time. Once EN UVLO or OTP is triggered, PG is pulled low within 1.7us deglitch time even FB voltage is JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 12 / 20 JWH5086A JoulWatt still in threshold range. If the input supply fails to power the JWH5086A, PG is clamped low even though PG is tied to an external DC source through a pull-up resistor. Thermal Protection When the temperature of the JWH5086A rises above 160°C, it is forced into thermal shut-down and SS capacitor is discharged. Only when core temperature drops below 130°C can the regulator become active again. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 13 / 20 JWH5086A JoulWatt APPLICATION INFORMATION Output Voltage Set The output voltage is determined by the resistor divider connected at the FB pin, and the voltage ratio is: RL VFB = VOUT ∗ RH + RL where VFB is the feedback voltage and VOUT is the output voltage. To improve efficiency at very light load, using larger value resistors is preferred. However, using too high of resistance causes the circuit to be more susceptible to noise, and voltage errors from the VFB input current will be more noticeable. If RH is determined, such as 2kΩ, and then RL can be calculated by: RL = RH VOUT 0.6 − 1 the following equation when the input ripple voltage is determined. IOUT VOUT VOUT CIN = ∗ ∗ (1 − ) FSW ∗ ∆VIN VIN VIN where CIN is the input capacitance value, FSW is the switching frequency, △VIN is the input ripple voltage. The input capacitor can be electrolytic, tantalum or ceramic. To minimizing the potential noise, a small X5R or X7R ceramic capacitor, e.g., 0.1μF, should be placed as close to the IC as possible when using electrolytic capacitors. 3x10μF/25V ceramic capacitors are recommended in typical application. Output Capacitor The output capacitor is required to maintain the DC output voltage, and the capacitance value determines the output ripple voltage. The output voltage ripple can be calculated by: VOUT VOUT VOUT 1 ∗ (1 − ) ∗ (R ESR + ) FSW ∗ L VIN 8 ∗ FSW ∗ COUT RH ∆VOUT = RL where COUT is the output capacitance value and RESR is the equivalent series resistance value of the output capacitor. FB Input Capacitor The input capacitor is used to supply the AC input current to the step-down converter and maintain the DC input voltage. The capacitors must have a ripple current rating that exceeds the converter’s maximum input ripple current. The RMS ripple current through the input capacitor can be calculated by: VOUT VOUT ICIN = IOUT ∗ √ ∗ (1 − ) VIN VIN where IOUT is the load current, VOUT is the output voltage, VIN is the input voltage. Thus, the input capacitor can be calculated by The output capacitor can be low ESR electrolytic, tantalum or ceramic, which lower ESR capacitors get lower output ripple voltage. The output capacitors also affect the system stability and transient response, and at least 5x47μF ceramic capacitors are recommended in typical application. Inductor The inductor is used to supply constant current to the output load, and the value determines the ripple current which affect the efficiency and the output voltage ripple. The ripple current is typically allowed to be 40% of the maximum JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 14 / 20 JWH5086A JoulWatt switch current limit, thus the inductance value can be calculated by: VOUT VOUT L= ∗ (1 − ) FSW ∗ ∆IL VIN where VIN is the input voltage, VOUT is the output voltage, FSW is the switching frequency, and △IL is the peak-to-peak inductor ripple current. External Bootstrap Capacitor The bootstrap capacitor is required to supply voltage to the top switch driver. A 0.1μF low ESR ceramic capacitor is recommended to connected to the BST pin and SW pin. 5. 6. 7. PCB Layout Note The PCB layout is critical for best operating performance, follow the guidelines as below. 1. Place the input decoupling capacitor as close to device (VIN pin and PGND) as possible to eliminate noise at the input pin. The loop area formed by input capacitor and GND must be minimized. 2. A solid ground inner plane is recommended to isolate the signal traces from noisy power traces. 3. AGND Pin (Pin 2) is recommended to be connected to a solid PGND plane on inner layer. 4. If a solid PGND plane on inner layer is not available for PCB design, it is highly 8. 9. 10. recommended to connect the AGND to the point of the VOUT capacitor’s ground directly. Alternatively, connect AGND and PGND at the point of the VCC capacitor’s ground, and place output capacitors close to VCC decoupling capacitor, then make the PGND connection using an entire copper plane on top layer. Place as many PGND vias as possible and make the ground plane as large as possible to optimize heat dissipation and parasitic impedance. Place the VCC decoupling capacitor as close as possible to the device. Place the BST capacitor as close as possible to the BST and SW pins. 20mil or wider traces are recommended for the connection. Place the feedback resistors close to device to minimize the feedback trace, and put the feedback trace far away from the inductor and noisy power traces like SW node. It is recommended to shield the pair of remote sensing traces with ground planes above and below. Keep the switching node SW short to prevent excessive capacitive coupling. Make VIN, VOUT and ground bus connections as wide as possible to reduce voltage drop on the input and output paths of the converter and maximize efficiency. JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 15 / 20 JWH5086A JoulWatt 0603 0603 VOUTSNS+ VOUTSNS0603 Via down to solid PGND plane on inner layer 0603 0603 PG EN BST AGND CS MODE SS RGND FB EN PG 0603 MODE 4 3 14 15 16 17 PGND PGND PGND PGND PGND PGND 0402 5 13 PGND 19 6 12 1 7 11 18 8 2 9 VIN 0402 20 SW 1206 21 VIN 10 VIN 1206 SW VCC PGND L 0603 0603 1206 PGND VOUT 1206 PCB Layout Recommendation JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 16 / 20 JWH5086A JoulWatt TAPE AND REEL INFORMATION Reel UNIT: mm φ W4 W1 W2 Package Diameter Ф Thickness W1 Width W2 W4 QFN3*4-21 330±2 17.6±2 12.4±2 100±2 JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 17 / 20 JWH5086A JoulWatt Carrier Tape UNIT: mm P2 P0 B T F E Φ1 W B0 Φ2 A A B SECTION B-B K0 P1 A0 SECTION A-A Note： 1) The carrier type is black , and colorless transparent . 2) Carrier camber is within 1mm in 100 mm. 3) 10 pocket hole pitch cumulative tolerance:±0.20. 4) All dimensions are in mm . Package QFN3*4-21 Tape dimensions (mm） P0 P2 P1 A0 B0 4.0±0.1 2.0±0.1 8.0±0.1 3.30±0.2 4.30±0.2 W 12±0.3 T K0 Φ1 Φ2 E F 0.25±0.1 1.1±0.15 1.5±0.10 1.55±0.1 1.75±0.1 5.50±0.10 JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 18 / 20 JWH5086A JoulWatt PACKAGE OUTLINE QFN3X4-21 UNIT: mm SYM BOL M IL L IM E T E R M IN NOM MAX A 0 .8 0 0 .8 5 0 .9 0 A1 0 .0 0 0 .0 2 0 .0 5 A2 — 0 .6 5 — A3 0 .2 0 3 R E F 0 .1 5 0 .2 5 0 .2 0 b1 0 .3 0 0 .3 5 D 2 .9 0 3 .0 0 3 .1 0 E 3 .9 0 4 .0 0 4 .1 0 b e 0 .4 0 B S C e1 0 .5 0 B S C e2 0 .2 5 0 .6 0 B S C L 0 .4 0 0 .5 0 L1 0 .5 0 0 .6 0 0 .7 0 L2 1 .6 0 1 .7 0 1 .8 0 L3 0 .6 0 0 .1 5 R E F QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPAE Sprocket Holes 1 2 1 2 1 2 3 4 3 4 3 4 Procket Quadrants Package Type Pin1 Quadrant QFN3X4-21 1 JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 19 / 20 JWH5086A JoulWatt IMPORTANT NOTICE  Joulwatt Technology Co.,Ltd reserves the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein.  Any unauthorized redistribution or copy of this document for any purpose is strictly forbidden.  Joulwatt Technology Co.,Ltd does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales channel.  JOULWATT TECHNOLOGY CO.,LTD PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, SAFETY INFORMATION AND OTHER RESOURCES, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY RIGHTS. Copyright © 2022 JoulWatt All rights are reserved by Joulwatt Technology Co.,Ltd JWH5086A Rev.0.22 JoulWatt® Proprietary Information. Patent Protected. 2022/06/15 Unauthorized Photocopy and Duplication Prohibited. 20 / 20