DT V 400KHz Boost DC-DC Controller FEATURES GENERAL DESCRIPTION APPLICATIONS ORDER INFORMATION

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1 GENERAL DESCRIPTION The DT9150 is a 5V step-up DC/DC controller designed capable of deliver over 50V Output with proper external N-MOSFET devices. The DT9150 can work with most Power N-MOSFET devices, whose VDS does not exceed 100V, to construct a typical boost up DC-DC circuit. Different topology makes it workable with single-cell Li-ion Battery Supplied systems, two-cell Li-ion Battery Supplied systems, and multiple-cell Li-ion Battery Supplied systems or other kinds of High Voltage Supplied systems. The DT9150 includes under-voltage lockout and soft start protections. FEATURES Drives Up to 100V N-MOSFET Wide Operating Voltage: 3.0~7.5V Maximum Output Voltage: over 50V Up to 95% Efficiency 400KHz Fixed Switching Frequency 1.25V Feedback Voltage UVLO Adjustable Current Limit SOP8 Package APPLICATIONS Power Supply for fast charger Power Supply for 12/24/36/48V applications The DT9150 is available in SOP8 package. TYPICAL APPLICATION CIRCUIT PIN ASSIGNMENT ORDER INFORMATION FULL CODE PACKAGE OPTION DT9150SOPHx S: Sub-category, S=Standard OPH: Package Type, OPH=SOP8 x: Package Material Option, 1=Copper Wire TAPE & REEL, 2500EA/REEL DT9150 Datasheet Rev1.01, Dec 2015 Page 1

2 PIN DESCRIPTION PIN NO SYMBOL DESCRIPTTION 1 FB Feedback input. 2 COMP Compensation Input 3 NC Not Connected 4 CS Current Sense Input 5 DRV Drive Output 6 VIN Power Supply Input. 7 EN Chip Enable Input 8 GND Ground ABSOLUTE MAXIMUM RATINGS (Note 1) SYMBOL ITEMS VALUE UNIT V IN Input Voltage -0.3~8.0 V V IO All Other I/O Pins GND-0.3 to VDD+0.3 V P DMAX Power Dissipation 0.8 W P TR1 Thermal Resistance,SOP8, Θ JA 100 /W T J Junction Temperature -40~125 Tstg Storage Temperature -55 to 150 Tsolder Package Lead Soldering Temperature 260, 10s Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Recommended Operating Range indicates conditions for which the device is functional, but do not guarantee specific performance limits. Electrical Characteristics state DC and AC electrical specifications under particular test conditions which guarantee specific performance limits. This assumes that the device is within the Operating Range. Specifications are not guaranteed for parameters where no limit is given, however, the typical value is a good indication of device performance. RECOMMANDED OPERATING RANGE SYMBOL ITEMS VALUE UNIT V IN VIN Supply Voltage 3.0 to 7.5 V T OPT Operating Temperature -40 to +85 DT9150 Datasheet Rev1.01, Dec 2015 Page 2

3 ELECTRICAL CHARACTERISTICS The following specifications apply for V IN = V EN =3.6V T A =25 o C, unless specified otherwise. SYMBOL ITEMS CONDITIONS MIN TYP MAX UNIT V IN Input Voltage V VULVO UVLO Voltage 2.9 V UVHYS UVLO Hysterisis 250 mv V FB FB Pin Voltage V I FB FB Pin Input Bias Current µa I SHDN Shutdown Current µa I Q Quiescent Current V FB =0.4V µa F SW Switching Frequency 400 KHz D MAX Maximum Duty Cycle V FB =0V % VCS CS Threshold Voltage 100 mv V EN_H EN Minimum High Level 1.5 V V EN_L EN Maximum Low Level 0.4 V I EN EN Input Bias Current µa I DRV DRV Output Current 100 ma T SS Soft Start Time V IN Power On 5 ms DT9150 Datasheet Rev1.01, Dec 2015 Page 3

4 SIMPLIFIED BLOCK DIAGRAM OPERATION DESCRIPTIONS The DT9150 is a 5V step-up DC/DC controller designed capable of deliver over 50V Output with proper external N-MOSFET devices. The DT9150 can work with most Power N-MOSFET devices, whose VDS does not exceed 100V, to construct a typical boost up DC-DC circuit. Different topology makes it workable with single-cell Li-ion Battery Supplied systems, two-cell Li-ion Battery Supplied systems, and multiple-cell Li-ion Battery Supplied systems or other kinds of High Voltage Supplied systems. The DT9150 includes under-voltage lockout and soft start protections. DT9150 Datasheet Rev1.01, Dec 2015 Page 4

5 Additional Application Circuits 1. Application Circuits for VIN>7V The operating voltage for the DT9150 is V. If the system input voltage is beyond the range, then following circuit can be applied. In this way the Input Voltage can be expended to as high as VOUT. This is extraordinarily suitable for two-cell or multiple-cell Li-ion Battery powered systems. Please be noted: (1) A very low standby current is added through R4-D2 path. (2) The resistor R5 is just as a psudo load and can be omitted. (3) The UVLO level is about 0.7V higher than the typical circuit, so it is not suitable for single-cell or other kinds of low VIN applications. 2. Enhance efficiency for low Input Voltage When the Input Voltage is low, the efficiency could be lost. The way to enhance low VIN efficiency is called Output-Supplied Circuit, as shown below. Respectively the last circuit is called Input-Supplied Circuit. The only difference between the Output-Supplied and the Input-Supplied circuit is that the DT9150 is supplied from VOUT instead of VIN. This can set the DT9150 always operates at a voltage higher than VIN and is not affected by the VIN changing. Please be noted that: (1) The Standby current is a bit higher than the Input-Supplied circuit. But this is canceled when the device is not enabled. (2) The UVLO function is partially invalid. (3) The UVLO level is a bit higher than the Input-Supplied circuit. DT9150 Datasheet Rev1.01, Dec 2015 Page 5

6 TYPICAL OPERATING CHARACTERISTICS Tested under TA=25 C, unless otherwise specified 1. Efficiency for VOUT=9V, Input-Supplied method, using MOSFET DM Efficiency for VOUT=12V, Output-Supplied method, using MOSFET CS40N27. Note that efficiency is strong dependent with the MOSFET. DT9150 Datasheet Rev1.01, Dec 2015 Page 6

7 3. IQ and IOP 4. Frequency 5. DRV and SW for No Load 6. DRV and SW for Normal Load Channel 1: DRV; Channel 2: IL; Channel 3: SW; Channel 4: VOUT 7. Ripple for No Load 8. Ripple for Normal Load DT9150 Datasheet Rev1.01, Dec 2015 Page 7

8 9. Startup for No Load 10. Startup for Normal Load 11. Transient Response DT9150 Datasheet Rev1.01, Dec 2015 Page 8

9 APPLICATION INFORMATION MOSFET Selection The MOSFET is very important to the entire system regarding output power, efficiency and start-up voltage. Normally, the parameters such as VDS, RDSON and VTH are the most considered ones: - VDS must exceed the output Voltage. - RDSON affects both the efficiency and the maximum Inductor current. - VTH affects the start-up voltage. For single-cell Li-ion Supplied systems, VTH shall not be over 3V. DM3010 is suggested for most applications if the output voltage does not exceed 24V and the output power does not exceed 24W. Inductor Selection A 2.2~10μH inductor is recommended for most applications. If high efficiency is a critical requirement, a low DCR inductor should be selected. The inductor s saturation current rating should also exceed the peak input current, especially for high load current application. Output Voltage Setting Output Voltage is determined by the feedback resistor. The feedback voltage is internally set at 1.25V. For accurate Output Voltage settings, precision 1% resistors are recommended. The formula is shown below: VOUT = (1+R2/R1)*VFB Selection R1=100KΩ, then R2 can be derived from the above formula. Current Limiting The current flow through inductor as charging period is detected by a current sensing circuit through the CS pin. As the value comes across the current limiting threshold, the external N-MOSFET will be turned off so that the inductor will be forced to leave charging stage and enter discharging stage. Therefore, the inductor current will not increase over the current limiting threshold. The threshold voltage VCS is 0.1V, thus the Peak Current is: Ipk = VCS/RCS Capacitor Selection Small size ceramic capacitors are ideal for DT9150 application. A 220uF input capacitor and a 220uF output capacitor are suggested for most applications. For better voltage filtering, ceramic capacitors with low ESR are recommended. X5R and X7R types are suitable because of their wider voltage and temperature ranges. Diode Selection Using a Schottky diode is recommended in DT9150 applications because of its low forward voltage drop and fast reverse-recovery time. The current rating of the Schottky diode should exceed the peak current of the boost converter. The voltage rating should also exceed the target output voltage. Compensation Consideration Compensation scheme is available to provide different compensation solution for different application condition. Power Sequence In order to assure the normal soft start function for suppressing the inrush current the input voltage should be ready before EN pulls high. Soft-Start The function of soft-start is made for suppressing the inrush current to an acceptable value at the beginning of power on. The DT9150 provides a built-in soft-start function by clamping the output voltage of error amplifier so that the duty cycle of the PWM will be increased gradually in the soft-start period. DT9150 Datasheet Rev1.01, Dec 2015 Page 9

10 UVLO The Under-Voltage Lock Out function disables the DT9150 from malfunctioning when the power supply is too low, and recovers when the power supply goes high. Layout Considerations PCB layout is very important for high frequency switching regulators in order to keep the loop stable and minimize noise. For best performance of the DT9150, the following guidelines must be strictly followed. Input and Output capacitors should be placed close to the IC and connected to ground plane to reduce noise coupling. The GND pin should be connected to a strong ground plane for heat sinking and noise protection. Keep the main current traces as possible as short and wide. The DRV node is with high frequency voltage swing. It should be kept in a smallest area. Place the CS (on CS pin) and feedback components (on FB pin) as close as possible to the IC and keep away from the noisy devices. DT9150 Datasheet Rev1.01, Dec 2015 Page 10

11 PACKAGE OUTLINE SOP8 L θ SYMBOL DIMENSIONS IN MILLIMETERS DIMENSIONS IN INCH MIN MAX MIN MAX A A A b c D E E e 1.270(BSC) 0.050(BSC) L θ DT9150 Datasheet Rev1.01, Dec 2015 Page 11