SCT2650STER

芯 洲 科 SCT2650 技 Silicon Content Technology Rev. 1.1 4.5V-60V Vin, 5A, High Efficiency Step-down DCDC Converter with Programmable Frequency FEATURES DESCRIPTION            The SCT2650 is 5A buck converter with wide input voltage, ranging from 4.5V to 60V, which integrates an 80mΩ high-side MOSFET. The SCT2650, adopting the peak current mode control, supports the Pulse Skipping Modulation (PSM) which assists the converter on achieving high efficiency at light load or standby condition.     Wide Input Range: 4.5V-60V Up to 5A Continuous Output Current 0.8V ±1% Feedback Reference Voltage Integrated 80mΩ High-Side MOSFET Low Quiescent Current: 175uA Pulse Skipping Mode (PSM) in light load 130ns Minimum On-time 4ms Internal Soft-start Time Adjustable Frequency 100KHz to 1.2MHz External Clock Synchronization Precision Enable Threshold for Programmable Input Voltage Under-Voltage Lock Out Protection (UVLO) Threshold and Hysteresis Low Dropout Mode Operation Derivable Inverting Voltage Regulator Over-voltage and Over-Temperature Protection Available in an ESOP-8 Package APPLICATIONS    12-V, 24-V, 48-V Industry and Telecom Power System Industrial Automation and Motor Control Vehicle Accessories The SCT2650 features programmable switching frequency from 100kHz to 1.2MHz with an external resistor, which provides the flexibility to optimize either efficiency or external component size. The converter supports external clock synchronization with a frequency band from 100kHz to 1.2MHz. The SCT2650 allows power conversion from high input voltage to low output voltage with a minimum 130ns on-time of highside MOSFET. The device offers fixed 4ms soft start to prevent inrush current during the startup of output voltage ramping. The SCT2650 features external loop compensation to provide the flexibility to optimize either loop stability or loop response. The SCT2650 provides cycle-by-cycle current limit, thermal shutdown protection, output over-voltage protection and input voltage under-voltage protection. The device is available in an 8-pin ESOP-8 package. TYPICAL APPLICATION 100 90 BOOT VIN VIN D1 FB C5 R3 C4 80 VOUT R1 COMP RT/CLK R4 SW GND EN C1 C2 L1 R2 Efficiency(%) C3 70 60 50 40 30 Vout=3.3V 20 Vout=5V 10 0 0.001 Vout=12V 0.01 0.1 1 Output Current(A) Efficiency, Vin=24V, Fsw=500KHz 4.5V-60V, Asyncronous Buck Converter For more information www.silicontent.com © 2019 Silicon Content Technology Co., Ltd. All Rights Reserved Product Folder Links: SCT2650 1 SCT2650 REVISION HISTORY NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Revision 1.0: Production Revision 1.1: Update IEN_H in EC and system UVLO calculation formula by EN pin resistor divider DEVICE ORDER INFORMATION PART NUMBER PACKAGE MARKING PACKAGE DISCRIPTION SCT2650STE 2650 ESOP-8 1) For Tape & Reel, Add Suffix R (e.g. SCT2650STER) ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION Over operating free-air temperature unless otherwise noted(1) DESCRIPTION MIN MAX UNIT VIN, EN -0.3 65 V BOOT -0.3 71 V SW -1 65 V BOOT-SW -0.3 6 V COMP, FB, RT/CLK -0.3 6 V Operating junction temperature TJ(2) -40 150 °C Storage temperature TSTG -65 150 °C (1) (2) BOOT 1 VIN 2 EN 3 RT/CLK 4 Thermal Pad 8 SW 7 GND 6 COMP 5 FB Figure 1. 8-Lead Plastic ESOP Stresses beyond those listed under Absolute Maximum Rating may cause device permanent damage. The device is not guaranteed to function outside of its Recommended Operation Conditions. The IC includes over temperature protection to protect the device during overload conditions. Junction temperature will exceed 150°C when over temperature protection is active. Continuous operation above the specified maximum operating junction temperature will reduce lifetime. PIN FUNCTIONS NAME NO. BOOT 1 VIN 2 EN 3 RT/CLK 4 FB 5 COMP 6 2 PIN FUNCTION Power supply bias for high-side power MOSFET gate driver. Connect a 0.1uF capacitor from BOOT pin to SW pin. Bootstrap capacitor is charged when SW voltage is low. Input supply voltage. Connect a local bypass capacitor from VIN pin to GND pin. Path from VIN pin to high frequency bypass capacitor and GND must be as short as possible. Enable pin to the regulator with internal pull-up current source. Pull below 1.05V to disable the converter. Float or connect to VIN to enable the converter. The tap of resistor divider from VIN to GND connecting EN pin can adjust the input voltage lockout threshold. Set the internal oscillator clock frequency or synchronize to an external clock. Connect a resistor from this pin to ground to set switching frequency. An external clock can be input directly to the RT/CLK pin. The internal oscillator synchronizes to the external clock frequency with PLL. If detected clocking edges stops, the operation mode automatically returns to resistor programmed frequency. Inverting input of the trans-conductance error amplifier. The tap of external feedback resistor divider from the output to GND sets the output voltage. The device regulates FB voltage to the internal reference value of 0.8V typical. Error amplifier output. Connect to frequency loop compensation network. For more information www.silicontent.com © 2019 Silicon Content Technology Co., Ltd. All Rights Reserved Product Folder Links: SCT2650 SCT2650 GND 7 Ground SW Thermal Pad 8 Regulator switching output. Connect SW to an external power inductor Heat dissipation path of die. Electrically connection to GND pin. Must be connected to ground plane on PCB for proper operation and optimized thermal performance. 9 RECOMMENDED OPERATING CONDITIONS Over operating free-air temperature range unless otherwise noted PARAMETER DEFINITION VIN VOUT TJ Input voltage range Output voltage range Operating junction temperature MIN MAX UNIT 4.5 0.8 -40 60 57 150 V V °C MIN MAX UNIT -1 +1 kV -0.5 +0.5 kV ESD RATINGS PARAMETER DEFINITION Human Body Model(HBM), per ANSI-JEDEC-JS-001-2014 specification, all pins(1) Charged Device Model(CDM), per ANSI-JEDEC-JS-0022014 specification, all pins(2) VESD (1) JEDEC document JEP155 states that 500V HBM allows safe manufacturing with a standard ESD control process. (2) JEDEC document JEP157 states that 250V CDM allows safe manufacturing with a standard ESD control process. THERMAL INFORMATION PARAMETER THERMAL METRIC ESOP-8L 𝜃𝑗𝑎 Junction-to-ambient thermal resistance (standard board) 42 𝜓𝑗𝑡 Junction-to-top characterization parameter 5.9 UNIT °C/W ELECTRICAL CHARACTERISTICS VIN=24V, TJ=-40°C~125°C, typical value is tested under 25°C. SYMBOL PARAMETER TEST CONDITION Power Supply VIN Operating input voltage ISHDN Input UVLO Threshold Hysteresis Shutdown current from VIN pin IQ Quiescent current from VIN pin VIN_UVLO MIN TYP 4.5 VIN rising 4.2 320 2 EN=0, no load EN floating, no load, nonswitching, BOOT-SW=5V Power MOSFETs RDSON_H High-side MOSFET on-resistance VBOOT-VSW=5V Reference and Control Loop VREF Reference voltage of FB 0.792 MAX UNIT 60 V 4.4 V mV μA 5 175 μA 80 mΩ 0.8 0.808 V GEA Error amplifier trans-conductance -2μA