TD1465

Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter General Description Features TD1465 is a 600mA synchronous buck converter with    integrated 900mpower MOSFETs. The TD1465 design with a current-mode control scheme, can convert wide input voltage of 4.5V to 40V to the output voltage adjustable from 0.8V to 75%VIN to provide excellent output voltage regulation. The TD1465 equipped with Power-on-reset, soft start and whole protections (under-voltage, over temperature and current-limit) into a single package. This device, available SOT-23-6 provides a very compact system solution of external components and PCB area.            TD1465 Wide Input Voltage from 4.5V to 40V 600mA Output Current High Efficiency over 85% from Load Current 30mA to 100mA @ VOUT>=5V Low EMI Converter Adjustable Output Voltage from 0.8V to 75%VIN Integrated 900m High/Low Side MOSFET 1M or 2Mhz Switching Frequency Stable with Low ESR Capacitors Power-On-Reset Detection Over-Temperature Protection Current-Limit Protection Enable/Shutdown Function Available in SOT-23-6 packages Lead Free and Green Devices Available (RoHS compliant) Applications ● Smart Electronic equipments Package Types SOT23-6 Figure 1. Package Types of TD1465 December, 15, 2012. Techcode Semiconductor Limited 1 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Pin Configurations Figure 2 Pin Configuration of TD1465(Top View) Pin Description Pin Number Pin Name 1 BS Description High-Side Gate Drive Boost Input. BS supplies the voltage to drive the high-side N-channel MOSFET. At least 10nF capacitor should be connected from SW to BS to supply the high side switch. 2 GND 3 FB Signal and power ground. Output feedback Input. The TD1465 senses the feedback voltage via FB and regulates the voltage at 0.8V. Connecting FB with a resistor-divider from the converter ’s output sets the output voltage from 1V to 80%V IN. Enable Input. EN is a digital input that turns the regulator on or off. EN threshold is 1.4V with 0.2V hysteresis. Pull up 4 EN with 100kΩ resistor for automatic startup. Power Input. VIN supplies the power (4.5V to 40V) to the control circuitry, gate drivers and step-down converter 5 VIN switches. Connecting a ceramic bypass capacitor and a suitably large capacitor between VIN and GND eliminates switching noise and voltage ripple on the input to the IC. 6 December, 15, 2012. SW Power Switching Output. It is the Drain of the N-Channel power MOSFET to supply power to the output LC filter. Techcode Semiconductor Limited 2 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Ordering Information TD1465□ □ □ Circuit Type Frequency: A-1MHz B-2MHz Packing: Blank：Tube R:Type and Reel Package T:SOT23-6 Function Block Figure 3 Function Block Diagram of TD1465 December, 15, 2012. Techcode Semiconductor Limited 3 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Absolute Maximum Ratings Note1 Symbol Parameter VIN VIN Supply Voltage (VIN to GND) VSW SW to GND Voltage Rating Unit -0.3 ~ 45 V Pulse Width > 20ns -1 ~ 45 V Pulse Width < 20ns -3 ~ 45 V -0.3 ~ 6 V VSW -0.3 ~ VSW +6 V EN, FB to GND Voltage VBS BS to GND Voltage VBS-SW BS to SW Voltage -0.3 ~ 6 V PD Power Dissipation Internally Limited W TJ Junction Temperature 150 oC TSTG Storage Temperature -65 ~ 150 oC TSDR Maximum Lead Soldering Temperature (10 Seconds) 260 oC Note1: Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Thermal Characteristics Symbol JA Parameter Junction-to-Ambient Resistance in free air Typical Value Unit 250 °C/W (Note 2) SOT-23-6 Note 2: JA is measured with the component mounted on a high effective thermal conductivity test board in free air. Recommended Operation ConditionsNote3 Symbol VIN Parameter Range Unit VIN Supply Voltage 4.5 ~ 40 V 0.8V ~ 75%VIN V 0 ~ 300 mA VOUT Converter Output Voltage IOUT Converter Output Current Continue < 10ms VOUT/VIN Maximum Ratio VOUT/VIN Minimum Ratio Note 4 Note 5 0 ~ 600 mA TD1465A 75 % TD1465B 65 % TD1465A 12 % TD1465B 15 % TA Ambient Temperature -40 ~ 85 oC TJ Junction Temperature -40 ~ 125 oC Note 3: Refer to the typical application circuit December, 15, 2012. Techcode Semiconductor Limited 4 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Note 4: In applications where he VOUT/VIN ratio exceeds the Maximum Ratio and when output loading is sufficient to make the converter enter PWM mode, the VOUT voltage will probably drop. Note 5: When operating below the VOUT/VIN Minimum Ratio, the converter has the likelihood of entering PSM mode in spite of loading is heavy. However, In PSM mode, the VOUT voltage is still regulated well. Electrical Characteristics Unless otherwise specified, these specifications apply over VIN=12V, VEN=3V and TA= -40 to 85 oC. Typical values are at TA=25oC. Parameter TD1465A/B Symbol Unit Test Conditions Min Typ Max SUPPLY CURRENT IVIN VIN Supply Current VFB=1V, SW=NC - 0.5 1.0 mA IVIN_SD VIN Shutdown Supply Current VEN=0V - 1 10 A 3.7 3.9 4.1 V - 0.6 - V - 0.8 - V -3 - +3 % - 10 50 nA TD1465B 1600 2000 2400 kHz TD1465A 800 1000 80 - - % - 60 80 ns High Side MOSFET Resistance - 900 - m Low Side MOSFET Resistance - 900 - m - - 2 A - - 2 A - 10 - ns POWER-ON-RESET (POR) VIN POR Voltage Threshold VIN Rising VIN POR Hysteresis REFERENCE VOLTAGE VREF Reference Voltage Output Voltage Accuracy IFB TJ=25°C, IOUT=10mA FB input current OSCILLATOR AND DUTY CYCLE FSW DMAX Switching Frequency SW Maximum Duty Cycle Note6 Minimum on-time 1200 kHz POWER MOSFET High Side Switch Leakage VEN=0V, VIN=40V, Current VSW=0V VEN=0V, VIN=40V, Low Side Switch Leakage Current VSW=40V Dead-time December, 15, 2012. Techcode Semiconductor Limited 5 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Electrical Characteristics(Cont.) Unless otherwise specified, these specifications apply over VIN=12V, VEN=3V and TA= -40 to 85 oC. Typical values are at TA=25oC. Parameter Symbol TD1465A/B Unit Test Conditions Min Typ Max PROTECTIONS ILIM High Side MOSFET Current-Limit 1.2 1.5 1.8 A Under-Voltage Protection (UVP) 40 50 60 %VREF Over-Temperature Protection - 150 - oC Over-Temperature Hysteresis - 30 - oC - 1 - ms SOFT-START, ENABLE tSS Soft Start Time EN Rising Threshold Voltage VIN=4.5V ~ 40V 1.2 1.4 1.6 V EN Falling Threshold Hysteresis VIN=4.5V ~ 40V - 0.2 - V - 50 - us EN Turn on delay EN Input Current VEN=2V EN Clamp High EN Input Current VEN=6V - 2 - uA 4 5 6 V - - 10 A Note 6: Supec guarantee the SW maximum duty cycle. The maximum percentage of converter output over input voltage depends on load current. December, 15, 2012. Techcode Semiconductor Limited 6 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Typical Application Circuit December, 15, 2012. Techcode Semiconductor Limited 7 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Function Description Main Control Loop Bootstrap Capacitor The TD1465 is a constant frequency, synchronous rectifier and The TD1465 is a N-channel MOSFET step down converter. The current-mode switching regulator. In normal peration, the internal MOSFET requires a gate voltage that is higher than input voltage, upper power MOSFET is turned on each cycle. The peak inductor thus a boost capacitor should be connected between SW and BST current at which ICMP turn off the upper MOSFET is controlled by pins to drive the gate of the N-channel MOSFET. Typical boostrap the voltage on the COMP node, which is the output of the error capacitor value is from 10nF to 100nF. amplifier (EAMP). An external resistive divider connected between Over-Current-Protection and Hiccup VOUT and ground allows the EAMP to receive an output feedback The TD1465 has a cycle-by-cycle over-current limit when the voltage VFB at FB pin. When the load current increases, it causes a inductor current peak value exceeds the set current limit threshold. slightly decrease in VFB relative to the 0.8V reference, which in turn Meanwhile, the output voltage drops until FB is below the causes the COMP voltage to increase until the average inductor Under-Voltage (UV) threshold below the reference. Once UV is current matches the new load current. triggered, the TD1465 enters hiccup mode to periodically restart VIN Power-On-Reset (POR) and EN Under-voltage Lockout the part.This protection mode is especially useful when the output The TD1465 keep monitoring the voltage on VIN pin to prevent is dead-shorted to ground. The average short circuit current is wrong logic operations which may occur when VIN voltage is not greatly reduced to alleviate thermal issues and to protect the high enough for the internal control circuitry to operate. The VIN regulator. The TD1465 exits the hiccup mode once the POR has a rising threshold of 3.9V (typical) with 0.6V of over-current condition is removed. hysteresis. Over-Temperature Protection (OTP) An external under-voltage lockout (UVLO) is sensed and The over-temperature circuit limits the junction temperature of the programmed at the EN pin. The EN UVLO has a rising threshold of TD1465 When the junction temperature exceeds 150oC, a thermal 1.4V with 0.2V of hysteresis. The EN UVLO should be sensor turns off the N-channel power MOSFET, allowing the programmed by connecting a resistive divider from VIN to EN to device to cool down. The thermal sensor allows the converter to GND. start a start-up process and regulate the output voltage again after After the VIN and EN voltages exceed their respective voltage the junction temperature cools by 30oC. The OTP designed with a thresholds, the IC starts a start-up process and then ramps up the 30oC hysteresis lowers the average TJ during continuous thermal output voltage to the setting of output voltage. Connect a RC overload conditions, increasing life time of the TD1465. network from EN to GND to set a turn-on delay that can be used to sequence the output voltages of multiple devices. Soft-Start The TD1465 provides built-in soft-start function to limit the inrush current. The soft-start time is 1ms. December, 15, 2012. Techcode Semiconductor Limited 8 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Package Information SOT23-6 Package Outline Dimensions December, 15, 2012. Techcode Semiconductor Limited 9 www.techcodesemi.com Techcode® DATASHEET 40V, 600mA, 2MHz/1MHz synchronous Buck Converter TD1465 Design Notes December, 15, 2012. Techcode Semiconductor Limited 10 www.techcodesemi.com