EC3651 E-CMOS | Alldatasheet

Document overview

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Technical content

Features

◆Integrate low RDS (on) power MOSFET ◆Wide VINrange:3.0V-16V ◆Wide VO range:0.9V-16V ◆Compatible with 4-switch buck-boost mode ◆and 2-switch boost mode. ◆Fixed frequency 500kHz ◆Programmable input and output current limit ◆Output Constant Current Control. ◆Quiescent current: <50uA ◆Integrate output overvoltage protection and ◆output short protection ◆Integrate thermal protection ◆QFN3*4 package

Applications

◆Power bank systems ◆USB Power Delivery ◆Industrial applications ◆Automotive Systems Typical application

16V 3A 4-Switch Buck-Boost Converter Ordering/Marking Information EC3651 XX X X R：Tape & Reel Package Type： F：Pb Free Q4=QFN3*4-15L G：Green Pin Configurations Device Marking Package Mark information EC3651Q4XR QFN3*4-15L

16V 3A 4-Switch Buck-Boost Converter Absolute Maximum Ratings Recommended Operating Conditions Thermal Performance Note 1) Exceeding these ratings may damage the device. 2) The EC3651 guarantees robust performance from -40°Cto 150°C junction temperature. The junction temperature range specification is assured by design, characterization and correlation with statistical process controls. 3) The EC3651 includes thermal protection that is intended to protect the device in overload conditions. Thermal protection is active when junction temperature exceeds the maximum operating junction temperature. Continuous operation over the specified absolute maximum operating junction temperature may damage the device. 4) Measured on JESD51-7, 4-layer PCB.

16V 3A 4-Switch Buck-Boost Converter

Electrical Characteristics

Notes: 5) Guaranteed by design. VIN=12V, TA=25 , unless otherwise stated Item Symbol Condition Min. Typ. Max Units General parameters VIN voltage range VIN 3.0 16 V VIN under voltage lockout VINUVLO VIN increasing 2.9 3.0 3. V VIN UVLO hysteresis VINHYS 320 400 48 mV VCC output voltage VCC 4.8 4.9 5. V VCC output current limit IVCC VVCC=0V 50 mA Supply current in shut- down mode IQ VIN=12V, VEN=0V 50 80 µA EN Logic HIGH VENH VEN increasing 2. V EN Logic LOW VENL VEN decreasing 1.6 V Switch frequency Fsw Optional switch frequency through tri m 400 500 60 kHz Switch minimum off time Toff_min 80 100 12 ns Bucktop switch on-resistance RdsbkTG 20 28 m Buck bottom switch on- resistance RdsbkBG 20 28 m Boost top switch on-resistance RdsbstTG 20 28 m Boost bottom switch on- resistance RdsbstBG 20 28 m Feedback voltage VFB 0.88 0.9 0.9 V Input average current limit IIN_LIM R1=10m ; R2=R3=3k ; 3 A OLIM pin output current sense r atio KOLIM IO=2A 4 5 6 µA/A OLIM pin regulate voltage VOLIM 380 400 42 mV Output average current limit IO_LIM ROLIM=40K 1.9 2 2. A Buck region, (IL Valley) ICOMP(MA VVCC 4.8V 7 A Boost region, (IL Peak) VVCC 4.8V 7 Protection VO over voltage threshold VO_OVP VO increasing 23.2 V VO decreasing 21.5 V VO OVP deglitch time tOVP 1.8 2 2. µS Thermal shutdown threshold5) TSHUT 150 °C Thermal recovery threshold5) TREC 130 °C

16V 3A 4-Switch Buck-Boost Converter Pin Description Notes: Highlighted pins are high current pins Pin No. Name Description 1 CSP Positive terminal of current sense. 2 VIN Input pin, place bypass capacitor close to this pin. 3 PGND Power Ground. 4 VO Output pin, place bypass capacitor close to this pin. 5 FB Output feedback pin.

6 OLIM

Output current limit program pin. Connect a resistor to GND to set the maximum average current. And in the light load, it could be output current detection pin. 7 EN Enable control pin. Forcing the pin below 1.6V shuts down the converter, reducing quiescent current. Once the EN pin rises above 2.0V, the IC is turned on. 8 BST1 VO side bootstrap supply pin for top switch. 0.1uF capacitor is connected between BST1 and SW1 pins. 9 SW1 VO side power switching node. 10 SW2 VIN side power switching node. Connect to SW1 with inductor 11 BST2 VIN side bootstrap supply pin for top switch. 0.1uF capacitor is connected between BST2 and SW2 pins. 12 NC No connection. 13 VCC 4.9V LDO for power driver and internal circuit. Must be bypassed to GN D with a minimum of 10uF ceramic capacitor for stable operation. 14 GND Signal GND. 15 CSN Negative terminal of current sense.

16V 3A 4-Switch Buck-Boost Converter Block Diagram Typical Performance Characteristics VIN =12V, VO = 5.0V, L = 3.3µH, CO = 40µF, TA = +25°C, unless otherwise noted

16V 3A 4-Switch Buck-Boost Converter Functional Description EC3651 is a monolithic buck -boost DC to DC converter that can operate over a wide input voltage range of 3.0V to 16V. The output voltage can be programmed between 0.9V to 16V and deliver 3A of load current. Internal, low RDSON N-channel power switches reduce the solution complexity and efficiency. Flexible Buck-Boost Converter The EC3651 contains flexible buck-boost converter for either buck or boost converter. When VINis higher than output voltage, it is a buck converter. When VIN is lower than output voltage, it is a boost converter. The DC-DC converter utilizes proprietary single inductor current-mode control to guarantee smooth transition between buck and boost operation with better dynamic response and cycle-by-cycle current protection. EC3651 regulates the output voltage and output current. Output Voltage The output voltage is set by an external feedback resistive divider. The feedback signal is compared with internal precision 0.9V voltage reference by the error amplifier. The output voltage is given by the equation: Where R4 and R5 are defined in typical application figure. Programmable Input/Output Current Limit As shown in figure1, the current sense resistor RCS should be placed input terminal or output terminal and closed To the RISET. The input/output current limit is set by RISET and RCS, which is optional. If the input/output current limit is not desired, the CSN pin should be shorted to VCC, and the CSP pin shorted to GND. Figure1. Programmable current limit If the input and output current limit are all necessary. The secondary output current limit can be programmable by ROLIM pin. If the output current equals to theIO_LIM, the output current loop begins to work, it turns down output voltage to limit the output power. When OLIM is not used, it should be shorted to GND. When output is shorted to ground, the EC3651 works as a buck converter, the output current is continuously sensed and limited to IO_LIM. When the output short is removed, the regulator comes into normal operation again. VIN UVLO When VIN decreases to VIN_UVLO, the discharging process is terminated. When the VIN recovers and is larger than VIN_UVLO, the EC3651 can re-discharge if the VEN is still high.

16V 3A 4-Switch Buck-Boost Converter Thermal Control When the junction temperature of the EC3651 rises above 135°C, it begins to reduce the output power to prevent the Temperature from rising further. If the junction temperature of the EC3651 rises above 150°C, the discharging process stops. Shut-down Mode The EC3651 shuts down when vo ltage at EN pin is below 1.6V. The entire regulator is off. Output Over Voltage Protection If the output voltage is larger than VO_OVP rising threshold, the device stops switching. Until the output voltage is Less than VO_OVP falling threshold, the device re -starts switching again. PCB Layout Note For minimum noise problem and best operating performance, the PCB is preferred to following the guidelines as reference. 1. Place the input decoupling capacitor as close to EC3651 (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. Put the feedback trace as far away from the inductor and noisy power traces as possible. 3. The ground plane on the PCB should be as large as possible for better heat dissipation . Reference Design Reference 1：Input and output current limit set VIN: 3.0V ~ 16 V VOUT: 5.0V IIN_LIM : 3A IO_LIM : 2A

16V 3A 4-Switch Buck-Boost Converter Reference 2：Only output current limit set VIN: 3.0V ~ 16 V VOUT: 5.0V IO_LIM : 2A Reference 3：2-switch mode and no current limit VIN: 5.0V ~ 10 V VOUT: 12V IO: 0~2A

16V 3A 4-Switch Buck-Boost Converter Package Outline QFN3X4-15