CSM3502

U3502 DATA SHEET ZHEJIANG UNIU-NE Technology CO.,LTD 浙 江 宇 力 微 新 能 源 科 技 有 限 公 司 U3502 Data Sheet V 1.0 版权归浙江宇力微新能源科技有限公司 www.uni-semic.com 0575-85087896 U3502 DATA SHEET 100V Input,2A, Switching Current Limit Step-Down Converter General Description Key Features The U3502 is a high-voltage, stepdown, switching regulator that delivers up to 2A of max current to the load. It integrates a high-side, high-voltage, power MOSFET with a current limit of 5A, typically. The wide 10V to 100V input range accommodates a variety of stepdown applications, making it ideal for automotive, industry, and lighting applications. Hysteretic voltage-mode control is employed for very fast response. UNI’s proprietary feedback control scheme minimizes the number of required external components. The switching frequency is 120KHz, allowing for small component size. Thermal shutdown and short-circuit protection (SCP) provide reliable and faulttolerant operations. Low quiescent current allows the U3502 to be used in batterypowered applications. The U3502 is available in a ESOP-8 package with an exposed pad. The U3502 can cooperate with MCU to test VIN voltage(TE PIN), control internal logic shutdown and realize zero power consumption.           Wide 10V to 100V Input Range Built-In 100V/5A Typical Peak Switching Current Limit Built-in Bootstrap Diode Hysteretic Control: No Compensation 120KHz Switching Frequency PWM Dimming Control Input for stepdown Application Short-Circuit Protection (SCP) with Integrated High-Side MOSFET Low Quiescent Current Thermal Shutdown Available in a ESOP-8 Package with an Exposed Pad APPLICATIONS       Scooters, E-Bike Control Power Supplies Solar Energy Systems Automotive System Power Industrial Power Supplies High-Power LED Drivers USB Typical Application U3502 www.uni-semic.com 1 0575-85087896 U3502 DATA SHEET Ordering Information Part Number U3502 Package Rdson Vo VINMAX Load Current Description ESOP-8 96mΩ ＞2V 100V Io＜=2500mA 4000Pcs/Reel *For Tape & Reel, add suffix –Z (e.g. U3502–Z) Pin Description TOP VIEW 9 EP Pin Functions SOP-8 EP SOP-8 EP Pin # Name Description 1 VIN Input supply. VIN supplies power toallofthe internal control circuitries ,both BST regulators , and the high -side switch .A decoupling capacitor to ground must be placed close to VIN to minimizeswitchingspikes. 2 GND Ground. GND should beplaced asclose to the output capacitor aspossible toavoid the highcurrentswitchpaths.ConnecttheexposedpadtoGNDplaneforoptimalthermalperformance. 3 EN Enable input. Pull EN below the specified threshold to shut down the U3502. Pull EN above the specified threshold or leave EN floating to enable the U3502. 4 TE Test VIN voltage(TE PIN). control internal logic shutdown and realize zero power consumption.The ratio of pull-up resistance to pull-down resistance is about 30/1. 5 FB Feedback. FB is the input to the voltage hysteretic comparators. The average FB voltage is maintained at 200mV by loop regulation. 6 VB Boot. BST is the positive power supply for the internal, floating, high-side MOSFET driver. Connect a bypass capacitor between BST and SW. 7 SW Switch node. SW is the output from the high-side switch. A low forward voltage Schottky rectifier to ground is required. The rectifier must be placed close to SW to reduce switching spikes. 8 IS Current detection. Current Sensing Input. 9 EP Input supply. VIN supplies power toallofthe internal control circuitries ,both BST regulators , and the high -side switch .A decoupling capacitor to ground must be placed close to VIN to minimizeswitchingspikes. www.uni-semic.com 2 0575-85087896 U3502 DATA SHEET Block Diagram Figure 1:Function Block Diagram Absolute Maximum Ratings (Note 1) Parameter Value Unit -0.3 to 120 V VB Supply Voltage 120+7 V VB Clamp Current 1 mA -0.3 to 7 V Package Thermal Resistance ---Junction to Ambient (ESOP-8) 165 °C/W Maximum Junction Temperature 160 °C -65 to 150 °C 260 °C 3 kV 250 V VIN,SW Pin Voltage Range FB, IS, EN Voltage Range Storage Temperature Range Lead Temperature (Soldering, 10sec.) ESD Capability, HBM (Human Body Model) ESD Capability, MM (Machine Model) www.uni-semic.com 3 0575-85087896 U3502 DATA SHEET ELECTRICAL CHARACTERISTICS VIN = 60V, TA = +25°C, unless otherwise noted. Specifications over temperature are guaranteed by design and characterization. Parameter Symbol Condition Min Typ Max Units VIN UVLO threshold — 10.0 — V VIN UVLO hysteresis — 0.4 — V Shutdown supply current VEN = 0V — 1.8 — µA Quiescent supply current No load, DIM = low, VFB = 1.25V — 300 — µA RDS(ON) VBST - VSW = 5V — 150 — mΩ ISWLK VEN = 0V, VSW = 0V — 0.02 1.5 µA IPK VFB = 1.25V — 3.5 — A Upper switch on resistance Upper switch leakage current Current limit Working frequency Fsw — 120 — KHz EN -on VENH — 2.8 7 V EN -off VENL — — 1 V EN threshold hysteresis VENHY — 500 — mV EN input current IENI VEN = 5V — 0.01 1.5 µA EN pull-up current IENS VEN = 2V — 2 3 µA Feedback voltage threshold VFBH 1.22 1.25 1.28 V IFB VFB = 5V or 0V -800 — 800 nA FB propagation delay to output high TFBDH Falling edge of VFB from1.25V to 0V to VSW rising edge — 100 — ns FB propagation delay to output high TFBDL Rising edge of VFB from 0V to 1.25V to VSW falling edge — 100 — ns Trigger thermal shutdown — 150 — Hysteresis — 20 — FB input current Thermal shutdown C NOTES: Note1. Stresses listed as the above “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 maximum rating conditions for extended periods may remain possibility to affect device reliability. Note2. The device is not guaranteed to function outside its operating conditions. Note3. Guaranteed by design. www.uni-semic.com 4 0575-85087896 U3502 DATA SHEET Typical Characteristics VIN = 60V, TA = +25°C, unless otherwise noted. Shutdown Current vs. Input Voltage Quiesvent Current vs. Input Voltage 320 EN=HIGH, DIM=LOW, VFB=1.25V 5 4.5 4 3.5 3 2.5 2 1.5 1 0.5 0 Input Current(uA) Input Current(uA) EN=LOW 310 300 290 280 4 17 30 43 56 69 82 95 4 17 30 Input Voltage(V) 69 82 95 VIN=95V, DIM=LOW,EN=HIGH,VFB=250mV VIN=95V, EN=LOW 320 Input Current(uA) 16 Input Current(uA) 56 Quiescent Current vs. Temperature Shutdown Current vs. Temperature 20 43 Input Voltage(V) 12 8 4 310 300 290 280 0 -40 -20 0 20 40 -40 -20 0 20 60 80 100 120 140 40 60 80 100 120 140 J unction Temperature(oC) J unction Temperature(oC) UVLO Threshold vs. Temperature EN Threshold vs. Temperature 10.5 3.5 rising 3.2 falling EN Threshold(V) Vin Threshold(V) 10.3 10.1 9.9 2.9 2.6 9.7 2.3 9.5 2.0 -40 -20 0 20 40 J unction 60 rising fallin g -40 -20 80 100 120 140 0 20 40 60 80 100 120 140 J unction Temperature(oC) Temperature(oC) www.uni-semic.com 5 0575-85087896 U3502 DATA SHEET Typical Performance Characteristics VIN = 60V, VOUT = 12V, IOUT = 1A, L = 47μH, COUT = 100μF, TA = +25°C, unless otherwise noted. 100 90 80 70 60 50 40 30 20 10 0 Load Regulation Regulation Error(%) Efficiency(%) Efficiency vs. Output Current Vin=36V Vin=60V 1 10 100 Output Current(mA) 1000 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1 Vin=36V Vin=60V 0 200 400 600 800 1000 Output Current(mA) Line Regulation 2 Iout=5mA Regulation Error(%) 1.5 Iout=1000mA 1 0.5 0 -0.5 -1 -1.5 -2 0 10 20 30 40 50 60 70 80 90 100 Input Voltage(V) www.uni-semic.com 6 0575-85087896 U3502 DATA SHEET Operation Hysteresis Current Control with Adaptive Threshold Adjustment The U3502 operates in a hysteretic voltagecontrol mode to regulate the output voltage. FB is connected to the tap of a resistor divider, which determines the output voltage. The power MOSFET is turned on when the FB voltage (VFB) rises to FBon and remains on until VFB rises to FBoff. The power MOSFET is turned off when VFB drops to FBoff and remains off until VFB falls to FBon. The two thresholds of FBon and FBoff are adjusted adaptively to compensate for all the circuit delays, so the output voltage is regulated with an average 1.25V value at FB. Enable (EN) Control Under-Voltage Lockout (UVLO) Under-voltage lockout (UVLO) is implemented to protect the chip from operating at an insufficient supply voltage. The UVLO rising threshold is threshold is a about 10V, while its falling consistent 9.5V. Fast charging Function for USB Applications Because the FB reference of the U3502 is very flexible, it is recommended to use the U3502 for USB Fast charging Applications by connecting the current sense resistor between FB and GND. Thermal Shutdown Thermal shutdown is implemented to prevent the chip from operating at exceedingly high temperatures. When the silicon die temperature is higher than its upper threshold, the entire chip shuts down. When the temperature is lower than its lower threshold, the chip is enabled again. Output Short Protection The U3502 has a dedicated enable control pin (EN) with positive logic. Its falling threshold is 2.5V, and its rising threshold is 2.8V .When EN is pulled up to about 3V by an internal current source, so it is enabled. The output voltage is well-regulated when VFB is around 1.25V. If the output is pulled low in overcurrent protection (OCP) or is shorted to GND directly, VFB is low, even though the power MOSFET is turned on. The U3502 regards the low VFB as a failure. The power MOSFET shuts off if the failure time is longer than 10µs. The U3502 attempts operation again after a delay of about 300µs. The power MOSFET current is also accurately sensed via a current sense MOSFET. If the current is over the current limit, the IC is shut down. This offers extra protection under outputshort conditions. Floating Driver and Bootstrap Charging The floating power MOSFET driver is powered by an external bootstrap capacitor. This floating driver has its own under-voltage lockout (UVLO) protection. The UVLO rising threshold is 10V with a threshold error of 0.2V. The bootstrap capacitor is charged and regulated to about 5V by the dedicated internal bootstrap regulator. If the internal circuit does not have sufficient voltage, and the bootstrap capacitor is not sufficiently charged, extra external circuitry can be used to ensure that the bootstrap voltage is in the normal operating region. Refer to the External Bootstrap Diode section for more details. www.uni-semic.com 7 0575-85087896 U3502 DATA SHEET Application Information recommended that the inductor current be continuous in each switching period to prevent reaching the current limit. Calculate the inductor value with Equation (2): Setting the Output Voltage The output voltage (VOUT) is set by a resistor divider (R1 and R2) (see the Typical Application on page 1). To achieve good noise immunity and low power loss, R2 is recommended to be in the range of 1kΩ to 50kΩ. R1 can then be determined with Equation (1): R1  VOUT  VFB  R2 VFB L (VIN  VOUT )  VOUT FSW  I OUT  VIN  K (2) Where K is a coefficient of about 0. 15 ~ 0.85 Output Rectifier Diode The output rectifier diode supplies current to the inductor when the high-side switch is off. To reduce losses due to the diode forward voltage and recovery times, use a Schottky diode. The average current through the diode can be approximated with Equation (3): (1) Where VFB is 1.25V, typically. Output Capacitor and Frequency Setting The output capacitor (COUT) is necessary for achieving a smooth output voltage. The ESR of the capacitor should be sufficiently large compared to the capacitance; otherwise, the system may behave in an unexpected way, and the current ripple may be very high.VFB changes from 1.22V to 1.28V when the power MOSFET switches on. To charge the capacitor and generate 1.28V at FB, the system needs ESR and some inductor current. For example, for a 5V VOUT, if the forward capacitor is 0.1µF, the suggested ESR range of the output capacitor is 100mΩ to 250mΩ. Tantalum or aluminum electrolytic capacitors with a small ceramic capacitor are recommended. A forward capacitor across R1 is recommended when the output capacitor is tantalum or aluminum electrolytic, which can set the desired frequency if the output capacitor and ESR cannot be changed. The forward capacitor can reduce the output voltage ripple. In some application, simply a forward capacitor may not get proper frequency, then we can add a forward resistor in series with the forward capacitor or even more add a ceramic on the output. I D  I OUT  (1  VOUT ) VIN (3) Choose a diode with a maximum reverse voltage rating greater than the maximum input voltage and a current rating is greater than the average diode current. Input Capacitor (CIN) The input current to the step-down converter is discontinuous and therefore requires a capacitor to supply AC current to the step-down converter while maintaining the DC input voltage. Use low ESR capacitors for the best performance, especially under high switching frequency applications. The RMS current through the input capacitor can be calculated with Equation (4): I IN _ AC  I OUT  VOUT V  (1  OUT ) (4) VIN VIN With low ESR capacitors, the input voltage ripple can be estimated with Equation (5): VIN  I OUT  VOUT V  (1  OUT ) (5) FSW  C IN  VIN VIN Choose an input capacitor with enough RMS current rating and enough capacitance for small input voltage ripples. When electrolytic or tantalum capacitors are applied, a small, high-quality ceramic capacitor (i.e.: 0. 1μ F) should be placed as close to the IC as possible. Selecting the Inductor The inductor (L) is required to convert the switching voltage to a smooth current to the load. Although the output current is low, it is www.uni-semic.com 8 0575-85087896 U3502 DATA SHEET External Bootstrap Diode PCB Layout Guidelines An external bootstrap diode may enhance the efficiency of the converter (see Figure 2). The bootstrap diode can be a low-cost one, Optimize circuit structure, save cost, and reduce error rate for peripheral circuit configuration. Efficient PCB layout is critical for stable operation. For best results, refer to Figure 3 and follow the guidelines below. 1. Place the input decoupling capacitor, catch diode, and the U3502 (VIN, SW, and PGND) as close to each other as possible. 2. Keep the power traces very short and fairly wide, especially for the SW node. This can help greatly reduce voltage spikes on the SW node and lower the EMI noise level. 3. Run the feedback trace as far from the inductor and noisy power traces (like the SW node) as possible. 4. Place thermal vias with 15mil barrel diameter and 40mil pitch (distance between the centers) under the exposed pad to improve thermal conduction. U3502 Figure 2: External Bootstrap Diode www.uni-semic.com 9 0575-85087896 U3502 DATA SHEET Typical Application Circuit APP1: VIN = 18 ~ 95V, VOUT =12.5V, IOUT = 1A U3502 APP2: VIN = 18 ~ 95V, VOUT =5V, IOUT = 1.5A U3502 www.uni-semic.com 10 0575-85087896 U3502 DATA SHEET APP3: VIN = 18 ~ 95V, VOUT = 12.5V, IOUT = 1A(TE PIN zero power consumption） U3502 APP4: VIN = 18 ~ 95V, QC2.0/QC3.0 U3502 www.uni-semic.com 11 0575-85087896 U3502 DATA SHEET Package Information SOP-8 EP NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating UNI products into any application. UNI will not assume any legal responsibility for any said applications. www.uni-semic.com 12 0575-85087896 U3502 DATA SHEET 1.版本记录 DATE REV. DESCRIPTION 2018/02/16 1.0 First Release 2018/03/18 2.0 Package is changed to SOP-8 2019/05/20 3.0 Package is changed to ESOP-8 2019/10/15 3.1 Pin definition changed 2019/11/09 3.2 Add typical application circuits 2021/12/20 3.3 2022/04/08 1.0 Delete CSM3502E Rename CSM3502 to U3502 2.免责声明 浙江宇力微新能源科技有限公司保留对本文档的更改和解释权力，不另行通知! 产品不断提升， 以追求高品质、稳定性强、可靠性高、环保、节能、高效为目标，我司将竭诚为客户提供性价 比高的系统开发方案、技术支持等更优秀的服务。量产方案需使用方自行验证并自担所有批量 风险责任。未经我司授权，该文件不得私自复制和修改。 版权所有 浙江宇力微新能源科技有限公司/绍兴宇力半导体有限公司 3.联系我们 浙江宇力微新能源科技有限公司 总部地址：绍兴市越城区斗门街道袍渎路25号中节能科创园45幢4/5楼 电话：0575-85087896（研发部） 传真：0575-88125157 E-mail: htw@uni-semic.com 无锡地址：无锡市新吴区纺城大道299号深港都会广场9-1401 电 话 : 0510-85297939 E-mail: zh@uni-semic.com 深圳地址：深圳市宝安区航城街道三围社区南昌路上合工业园B2栋501 电 话 ：0755-84510976 E-mail: htw@uni-semic.com www.uni-semic.com 13 0575-85087896