EUP3268AWIR1

EUP3268A CC/CV Mode Synchronous Step-Down Converter DESCRIPTION FEATURES The EUP3268A is a synchronous step-down converter capable of driving 4A continuous load with excellent line and load regulation. The EUP3268A operates in either CC (Constant Current) mode or CV (Constant Voltage) mode with an input voltage range from 8V to 36V. The EUP3268A provides programmable cable compensation by adjusting external resistor divider. External shutdown function can be controlled by pulling COMP pin to a level below 0.14V. Fault protection includes secondary cycle-by-cycle current limit, short circuit protection and thermal shutdown. Internal soft-start minimizes the inrush supply current and the output overshoot at initial startup. The EUP3268A is available in SOP-8 (EP) package.













8V to 36V Wide Input Operating Range 80kHz~800kHz Switching Frequency Selection CC/CV Mode Control Up to 4A Output Current High Accurate Voltage Reference +/- 6% Constant Current Accuracy Programmable Cable Compensation Internal Soft Start Single Pin to External Compensation and Shutdown Control Hiccup Short Circuit Protection Secondary Cycle-by-Cycle Current Limit Thermal Shutdown Available in SOP-8 (EP) Package RoHS Compliant and 100% Lead(Pb)-Free Halogen-Free APPLICATIONS


Car Charger Portable charger applications DC/DC converters with current limited Typical Application Circuit Figure 1. Application Circuit DS3268A Ver1.1 July 2016 1 EUP3268A Block Diagram Figure 2. Functional Block Diagram Pin Configurations Package Type Pin Configurations SOP-8 (EP) Pin Description Pin Name SOP-8 (EP) VIN 1 Input Supply Pin. GND 2 COMP 3 FB 4 Ground. Loop compensation pin. Drive COMP voltage logic low to turn off the converter. Output Feedback Input. VDC 5 Internal VDC regulator output. Bypass VDC to ground with a ceramic capacitor. CS 6 Current sense input pin. FREQ 7 Frequency select pin. DRVL 8 Low-side switch drive pin. SW EP DS3268A Ver1.1 July 2016 DESCRIPTION Power switch pin. 2 EUP3268A Ordering Information Order Number Package Type Marking EUP3268AWIR1 SOP-8 (EP) xxxxx 3268A Quantity per Reel Operating Temperature Range 2500 EUP3268A □ □ □ □ Lead Free Code 1: Lead Free, Halogen Free Packing R: Tape & Reel Operating temperature range I: Industry Standard Package Type W: SOP (EP) DS3268A Ver1.1 July 2016 3 -40°C to +85°C EUP3268A Absolute Maximum Ratings (1)         Input Voltage (VIN) --------------------------------------------------------------Switch Voltage (VSW) ------------------------------------------------------------CS ----------------------------------------------------------------------------------All Other Pins ---------------------------------------------------------------------Junction Temperature ------------------------------------------------------------Storage Temperature -------------------------------------------------------------Lead Temp(Soldering, 10sec) --------------------------------------------------Thermal Resistance θJA (SOP-8_EP) ------------------------------------------ -0.3V to 40V -1V to VIN +0.3V -0.3V to 13V -0.3V to 6V 150°C -65°C to +150°C 260°C 60°C /W Recommend Operating Conditions (2) Supply Voltage (VIN) ------------------------------------------------------------ 8V to 36V  Operating Temperature Range ------------------------------------------------- -40°C to +85°C Note (1): Stress beyond those listed under “Absolute Maximum Ratings” may damage the device.  Note (2): The device is not guaranteed to function outside the recommended operating conditions. Electrical Characteristics (VIN=12V, TA=+25°C, IOUT=2.0A, unless otherwise specified) Parameter Input voltage Input No Load Current Quiescent Current Shutdown Current Input Under Voltage Lockout Threshold Rising Input Under Voltage Lockout Threshold Hysteresis Current Limit Operating frequency R6=0Ω Maximum Duty Cycle Minimum On-Time Reference Voltage of the Voltage Error Amplifier CS1/CS2 Reference Voltage Transconductance of Error Amplifier Reference Voltage of the Short Circuit Foldback Comparator COMP Enable Threshold Rising COMP Enable Threshold Hysteresis Thermal Shut-down Temperature PMOS Drain-Source On-State Resistance DS3268A Ver1.1 July 2016 Conditions EUP3268A Min. Typ. Max. 8 IOUT=0A VFB=0.8V VCOMP=0V 6.2 132 0.588 56.4 Temperature Rising Temperature Falling IOUT=1A 4 36 10 1 380 6.7 1 7.5 150 150 0.6 60 75 7.2 168 100 0.612 63.6 Unit V mA mA µA V V A kHz % ns V mV µA/V 0.24 V 0.14 40 150 100 V mV °C °C mΩ 90 EUP3268A Typical Operating Characteristics VIN=12V, VOUT=5V, TA=25°C, unless otherwise noted. DS3268A Ver1.1 July 2016 5 EUP3268A Typical Operating Characteristics (continued) VIN=12V, VOUT=5V, TA=25°C, unless otherwise noted. DS3268A Ver1.1 July 2016 6 EUP3268A Typical Operating Characteristics (continued) VIN=12V, VOUT=5V, TA=25°C, unless otherwise noted. DS3268A Ver1.1 July 2016 7 EUP3268A Functional Description Application Information The EUP3268A is a current-mode synchronous step-down converter with 8V to 36V input power supply. The device can provide up to 4A continuous current to the output. The EUP3268A uses current-mode architecture to control the regulator loop. The output voltage is measured at FB through a resistive voltage divider and amplified through the internal error amplifier. The output current of the transconductance error amplifier is presented at COMP pin where a RC network compensates the regulator loop. Slope compensation is internally added to eliminate subharmonic oscillation at high duty cycle. The slope compensation adds voltage ramp to the inductor current signal which reduces maximum inductor peak current at high duty cycles. CC/CV mode control The output voltage is set through a resistive voltage divider and can be expressed by the equation as follows The EUP3268A operates in either CC mode or CV mode. The CV mode regulates the output voltage. When output current reaches the CC threshold, the device enters CC mode to limit the output current. Programmable cable compensation The EUP3268A provides programmable cable compensation by adjusting the external resistor divider to compensate resistive voltage drop across the charger's output cable. Internal soft-start Internal soft-start minimizes the inrush supply current and the output overshoot at initial startup. Short circuit protection The EUP3268A provides the output short circuit protection function to prevent large output short circuit current from damaging the device. When output short happens, the device shuts down and returns to normal operation automatically when the short circuit condition is released. Thermal Shutdown The EUP3268A stops switching when its junction temperature exceeds 150°C and resumes when the temperature has dropped by 50°C to protect the device. DS3268A Ver1.1 July 2016 8 VOUT = 0.6V × (R1 + R 2) / R 2 Setting the CC current EUP3268A constant current value is set by the resistor R3 connected between the CS and GND pins. The CC current is determined by the equation as follows I CS = 0.06V / R 3 Setting the switching frequency The switching frequency is set by the resistor R4 connected between the FREQ and GND pins and can be expressed by the equation as follows f SW = 1011 / R 4 The switching frequency is 150kHz when R4=0Ω. Setting the cable compensation The EUP3428A provides programmable cable voltage drop compensation using the impedance at the FB pin to compensate voltage drop across the charger's output cable. The cable compensation voltage can be expressed as ∆VOUT = 38µ × (I OUT × R 3) × R1 By adjust the value of R1, the cable compensation voltage can be programmed. EUP3268A Packaging Information SOP-8 (EP) Remark: Exposed pad outline drawing is for reference only. SYMBOLS MILLIMETERS INCHES MIN. Normal MAX. MIN. Normal MAX. A 1.35 - 1.75 0.053 - 0.069 A1 0.00 - 0.25 0.000 - 0.010 D 4.80 4.90 5.00 0.189 0.193 0.197 E1 3.70 3.90 4.00 0.146 0.154 0.157 D1 2.67 2.97 3.50 0.105 0.117 0.138 E2 1.78 2.18 2.60 0.070 0.086 0.102 E 5.80 6.00 6.20 0.228 0.236 0.244 L 0.40 - 1.27 0.016 - 0.050 b 0.31 - 0.51 0.012 - 0.020 e DS3268A Ver1.1 July 2016 1.27 REF 0.050 REF 9