OB2107MP

OB2107 High Voltage BUCK Converter GENERAL DESCRIPTION FEATURES OB2107 is a High voltage hysteresis mode Buck converter. The input voltage can be as high as 80V and the output voltage is programmable by external resistor divider. It delivers up to 200mA load current with excellent line and load transient response. With On-Bright patented control scheme, OB2107 works with a wide input and output range with a minimum number of external components. ■ ■ OB2107 automatically adjusts the switching frequency based on the output power. It provides output short circuit protection, over temperature protection, under voltage lock-out and cycle by cycle over current protections. When output short circuit happens, OB2107 enters hiccup mode until short circuit condition is released, which greatly saves the energy loss and avoid the chip overheating. OB2107 provides soft startup control to avoid inrush output current. ■ ■ ■ ■ ■ ■ ■ Wide input voltage range (5.5V to 80V) Wide output voltage range (programmable by external resistor divider) Up to 200mA output current Excellent line and load transient response Minimum number of external components Output short-Circuit protection Over temperature protection Cycle-by-cycle over current protection Under voltage lock-out APPLICATIONS ■ ■ ■ LED lighting Portable device Motor driver OB2107 is provided with SOT23-6 package. TYPICAL APPLICATION + DC IN VIN NC GND NC SW FB + DC OUT OB2107 _ _ ©On-Bright Electronics Confidential -1- Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r GENERAL INFORMATION Pin Configuration The pin map of OB2107 in SOT23-6 package is shown as below. VIN NC GND NC SW FB Absolute Maximum Ratings Parameter Value VIN Voltage(room -0.3V to 80V temperature) SW Voltage -3V to VIN Min/Max Operating Junction -40 to 150 ℃ Temperature TJ Operating Ambient -40 to 85 ℃ Temperature TA Min/Max Storage Temperature -55 to 150 ℃ Tstg Lead Temperature (Soldering, 260 ℃ 10secs) Note: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, 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-rated conditions for extended periods may affect device reliability. Ordering Information Part Number Description OB2107MP SOT23-6, Halogen-free in T&R Package Dissipation Rating Package RJA (℃/W) SOT23-6 200 Recommended Operating Condition Symbol Parameter Min Max VIN Input Voltage 5.5 75 OB2107 High Voltage BUCK Converter X Package M: SOT23-6 ©On-Bright Electronics Confidential -2- Unit V X Package Green P:Green (Halogen-free) Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r Marking Information 107YWW . ZZZ s Y:Year Code WW:Week Code(01-52) ZZZ:Lot Code S:Internal Code TERMINAL ASSIGNMENTS Pin Num 1 2 3 Pin Name VIN GND SW 4 FB 5 6 NC NC ©On-Bright Electronics I/O I P O I Description External power supply input pin. Ground pin of the IC Power switch output Pin. Connect an inductor to this pin. Output voltage feedback pin. A 100pF capacitor close to the IC is recommended to be placed between this pin and pin GND. Confidential -3- Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r BLOCK DIAGRAM VIN Bandgap HGND High-Side Regulator Vcc Low-Side Regulator Bias Soft start UVLO VIN 2.0V FB Level Shift CMP Logic Hside Driver HGND SW Vcc ZCD Lside Driver OCP GND Output short protection OTP GND ©On-Bright Electronics Confidential -4- Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r ELECTRICAL CHARACTERISTICS (TA = 25℃, VIN=36V, if not otherwise noted) Symbol Parameter Supply Voltage Section Operation supply current Iq Quiescent supply current UVLO Threshold of UVLO Over temperature OTP protection threshold Over temperature OTP_HYS protection hysteresis BUCK Section Feedback compare Vref reference voltage Inductor peak current Ilimit limit threshold Inductor min Idemag demagnetizing current T_sst Soft start time T_hiccup Hiccup time FB threshold voltage for Vth_short vout short protection The max high side turn T_max_on on time T_deadtime Dead time Rdson of PMOS power Rdson_p transistor Rdson of NMOS power Rdson_n transistor Test Conditions Min Typ. switching no switching 700 550 4 1.9 Unit 5.5 uA uA V 180 ℃ 20 ℃ 2 0.405 Max 2.1 V 330 mA 160 mA 4 1 ms s 0.45 0.495 V 60 us 100 ns 4.5 9 Ω 1.7 3.4 Ω CHARACTERIZATION PLOTS Vcc_BV vs Temperature 2.20 95 2.12 91 2.04 87 Vcc_BV (V) Vref (V) Vref vs Temperature 1.96 1.88 1.80 -40 -10 20 50 80 110 140 79 75 -40 -10 20 50 80 110 140 Temperature(℃) Temperature(℃) ©On-Bright Electronics 83 Confidential -5- Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r OPERATION DESCRIPTION OB2107 is a high voltage hysteresis mode Buck converter. When FB voltage becomes lower than reference voltage and the inductor current is lower than the minimum demagnetizing current, the high side power transistor turns on to provide current to the output. When the inductor current increase to the current limit threshold value of 300mA (typical), OB2107 turns off the high side power transistor and then turns on the low side power transistor for after following. If the inductor current decreases to zero, the OB2107 turns off the low side power transistor. UVLO protection OB2107 integrated VIN under voltage lock-out protection (UVLO). When VIN rise up to above 4V (typical), OB2107 will start up and enter switching operation mode. When VIN decreases to under 4V (typical), OB2107 will stop switching operation. than the minimum demagnetizing threshold value of 160ma (typical), even the FB voltage is lower than the reference voltage, the high side power transistor can’t be turn on again. Just when the inductor current decrease to lower than the minimum demagnetizing threshold value, the high side power transistor is allowed to be turn on. Over temperature protection OB2107 turns off the switching operation mode when the IC junction temperature exceeds 180C (typical) and resumes the switching operation mode when the IC junction temperature drops to 160C (typical). Switching frequency When the load is lower than 1/2*Ilimit, OB2107 works in DCM mode and the average inductor current equals to the load current. The switching frequency determined by the following equation: Soft start OB2107 implements soft start function. During the start-up procedure, the output voltage increases up gradually. The soft start time is 4ms (typical). F= 2Iout 2 Ilimit* L * Vout(Vin-Vout) Vin When the load is higher than 1/2*Ilimit, OB2107 works in CCM mode and the average inductor current also equals to the load current. The switching frequency determined by the following equation: Short circuit protection At the end of soft startup, if output short circuit happens, the high side power transistor will not turn on after the last switching process finished. After around 1s (typical), OB2107 resumes soft start procedure. The threshold for output short circuit detection is 0.5V (typical) for FB voltage. F= Vout(Vin-Vout) 2 L Vin ( Ilimit - Iout) When the load is higher than1/2*(Ilimit+Idemag), OB2107 works at the maximum switching frequency of: Zero current detection (ZCD) OB2107 integrates Zero Current Detection (ZCD) function. During the low side power transistor turnon phase, ZCD module detects the inductor current by sensing the SW voltage. When it detects the inductor current decreases to zero, OB2107 turns off the low side power transistor. Fmax= Vout(Vin-Vout) L Vin ( Ilimit - Idemag ) High side voltage regulator OB2107 integrates a high side voltage regulator to generate a ’VIN-5V’ floating ground voltage to drive the high side power transistor. Current limit protection OB2107 integrates current limit protection to prevent the inductor from entering saturation. And the cycle by cycle current limiting is also part of the control process. After the high side power transistor turns on, the only turn off condition is the inductor current increase to the current limit threshold value of 330mA (typical) Demagnetizing control OB2107 integrated demagnetizing control function for preventing the inductor current cumulating cycle by cycle at the condition that the inductor current can’t demagnetize fully in one cycle. OB2107 detects the inductor demagnetizing current after the high side power transistor turns off, if the inductor current hasn’t decrease to lower ©On-Bright Electronics Confidential -6- Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r PACKAGE MECHANICAL DATA Symbol Dimensions In Millimeters Dimensions In Inches Min Max Min Max A 1.000 1.450 0.039 0.057 A1 0.000 0.150 0.000 0.006 A2 0.900 1.300 0.035 0.051 b 0.300 0.500 0.012 0.020 c 0.080 0.220 0.003 0.009 D 2.800 3.020 0.110 0.119 E 1.500 1.726 0.059 0.068 E1 2.600 3.000 0.102 0.118 e e1 ©On-Bright Electronics 0.950 (BSC) 1.800 0.037 (BSC) 2.000 Confidential -7- 0.071 0.079 Datasheet OB_DOC_DS_2107A0 OB2107 High Voltage BUCK Converter r IMPORTANT NOTICE RIGHT TO MAKE CHANGES On-Bright Electronics Corp. reserves the right to make corrections, modifications, enhancements, improvements and other changes to its products and services at any time and to discontinue any product or service without notice. Customers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. WARRANTY INFORMATION On-Bright Electronics Corp. warrants performance of its hardware products to the specifications applicable at the time of sale in accordance with its standard warranty. Testing and other quality control techniques are used to the extent it deems necessary to support this warranty. Except where mandated by government requirements, testing of all parameters of each product is not necessarily performed. On-Bright Electronics Corp. assumes no liability for application assistance or customer product design. Customers are responsible for their products and applications using On-Bright’s components, data sheet and application notes. To minimize the risks associated with customer products and applications, customers should provide adequate design and operating safeguards. LIFE SUPPORT On-Bright Electronics Corp.’s products are not designed to be used as components in devices intended to support or sustain human life. On-bright Electronics Corp. will not be held liable for any damages or claims resulting from the use of its products in medical applications. MILITARY On-Bright Electronics Corp.’s products are not designed for use in military applications. On-Bright Electronics Corp. will not be held liable for any damages or claims resulting from the use of its products in military application. ©On-Bright Electronics Confidential -8- Datasheet OB_DOC_DS_2107A0