OB2222LMCPA

OB2222LM High Precision Low Cost Power Switch GENERAL DESCRIPTION FEATURES OB2222LM is a high performance, high precision and low cost PWM Power switch for non-isolated buck and buck-boost application. It combines a dedicated current mode PWM controller with a high voltage power Bipolar in SOP8 package. Its built-in error amplifier is optimized for good overshoot and dynamic response for low cost and component count. With precise inner resistor divider, precise reference of EA ， constant voltage regulation of 5.0V at universal AC input can be guaranteed. Frequency reduction and burst mode control is implemented for high efficiency at light load. Good EMI performance is achieved with On-Bright proprietary frequency shuffling technique and soft base driver design. Low startup current and low operating current contribute to a reliable power on startup and low standby power consumption with OB2222LM. Constant power operation is supported at over load application with OB2222LM, which makes it suitable for small home appliance application where instant large power consumption is required such as start-up of a fan. OB2222LM offers power on soft start control and protection coverage with auto-recovery features including cycle-by-cycle current limiting, output short circuit protection, FB pin open loop protection, on-chip Over Temperature Protection (OTP), VDD Over Voltage Protection (OVP), Over Loading Protection （ OLP ） and VDD Under Voltage Lockout Protection (UVLO). The tone energy at below 20KHz is minimized in the design so that audio noise is eliminated during operation. OB2222LM is offered in SOP8 package.                 Universal AC input range and 5.0V output voltage Peak load operation with increased frequency Low cost and less BOM for buck and buckboost applications Current mode control 40kHz (typical) normal switching frequency Frequency-reduction and burst mode control for high efficiency Frequency shuffling for EMI improvement Power on soft-start Built-in Leading Edge Blanking (LEB) Cycle-by-cycle current limiting FB pin open loop protection Output short-circuit protection VDD Under Voltage Lockout with Hysteresis VDD OVP Over Loading Protection On-Chip OTP APPLICATIONS Low power AC/DC offline SMPS for  Small home appliance  Linear regulator/RCC replacement TYPICAL APPLICATION ©On-Bright Electronics Confidential -1- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch GENERAL INFORMATION Pin Configuration The pin map is shown as below for SOP8 FB 8 1 Topology 90~264Vac Input (open frame) 300mA Buck/Buck-Boost Note: Maximum continuous power with drain pattern C 2 connected 100mm PCB copper clad, at 85℃ ambient. GND 7 2 C Absolute Maximum Ratings Parameter C-B Voltage VDD Voltage FB Voltage CS Input Voltage Min/Max Operating Junction Temperature TJ Operating Ambient Temperature TA Min/Max Storage Temperature Tstg Lead Temperature (Soldering, 10secs) Note: Stresses beyond those SOP VDD 3 6 C CS 4 5 C Ordering Information Part Number Description OB2222LMCP SOP8, Pb-free, Tube OB2222LMCPA SOP8, Pb-free, T&R Package Dissipation Rating Package RθJA (℃/W) SOP8 90 Note: Drain Pin Connected 100mm2 PCB copper clad. -40 to 150 ℃ -40 to 85 ℃ -55 to 150 ℃ 260 ℃ 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. Output Power Table Topology Value 700V -0.3 to 20V -0.3 to 20V -0.3 to 7V 90~264Vac Input (open frame) 350mA Recommended Operating Condition Symbol Parameter Range VDD VDD Supply Voltage 4.5 to 6V Buck/Buck-Boost Note: Maximum continuous power with drain pattern 2 connected 100mm PCB copper clad, at 50℃ ambient. ©On-Bright Electronics Confidential -2- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch Marking Information TERMINAL ASSIGNMENTS Pin Num Pin Name 1 FB I 2 3 4 5/6/7/8 GND VDD CS C P P I O ©On-Bright Electronics I/O Description Output Voltage Feedback. This pin should connect a capacitor to ground. Ground Power Supply Current sense input Power bipolar collector pins. Confidential -3- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch BLOCK DIAGRAM C VDD LDO UVLO Base Driver AVDD POR OVP LEB OTP Open Loop FB PWM Generate Logic core OCP CS SCP R2 OLP Frequency Shuffling Vref EA OSC COMP GND R1 ©On-Bright Electronics PWM AVDD Confidential -4- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch ELECTRICAL CHARACTERISTICS (TA = 25℃, VDD=5.5V, if not otherwise noted) Symbol Parameter Supply Voltage (VDD) Section I_startup Startup Current I_VDD_op UVLO(ON) Test Conditions VDD=UVLO(off) -1V 10 uA Operation supply current 1.5 CS=0.5V Operation supply current 0.6 FB=6V VDD falling, gate 3 3.7 disappear VDD rising 10.5 11.5 Ramp VDD until gate 14 15 shut down Operation Current VDD Under Voltage Lockout Enter UVLO(OFF) VDD Under Voltage Lockout Exit OVP Min Typ. Max Unit Over voltage protection Threshold FB RegulationIn normal regulation, FB will be regulated to Voltage average of 5.15V Current Sense Input Section TLEB LEB time Over current detection Vth_oc Threshold voltage Td_oc OCP propagation delay Vth_scp Short Current protection threshold voltage Vth_flt CS floating protection threshold voltage EA Section Vref EA reference Kfb/vref FB divider coefficient Frequency Section Freq_nor Normal operation frequency Freq_pk IC Maximum frequency ∆f/Freq Frequency shuffling range F_shuffling Shuffling frequency Dmax Maximum Duty Cycle F_Burst Burst Mode Switch Frequency Base Driver Section Is_max Base sourcing maximum current Is_preoff Base sourcing current after pre-off Protection Section Vth_OLD FB pin open loop detection threshold voltage Td_OLP Over Load protection debounce time Power switch temperature for exiting over temperature protection OTP Power switch temperature for entering over temperature protection Power BJT Section 5.15 3.9 V 12.5 V 16 V V 475 500 525 mV 50 0.6 0.7 0.9 1.0 100 ns 0.8 V 1.1 V 1.44 1.5 1.56 V 3.43 36 40 44 KHz 65 KHz +/-8 % 78 Hz 7 11 15 % 20 KHz Collector-emitter breakdown voltage Ic=10mA, Ib=0 450 Vcbo Ic Collector-base breakdown voltage Collect Peak Current Ic=10mA 700 90 3 mA mA 0.515 10 V mS 125 ℃ 150 ℃ V 1.5 Confidential -5- mA 250 300 350 ns Vceo ©On-Bright Electronics 2.5 mA V A Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch CHARACTERIZATION PLOTS UVLO(OFF)(V) vs Temperature UVLO(OFF)(V) 14.0 13.0 12.0 11.0 10.0 9.0 -40 -10 20 50 80 110 140 Temperature(℃) Vth_oc(V) vs Temperature 0.55 Vth_oc(V) 0.53 0.51 0.49 0.47 0.45 -40 -10 20 50 80 110 140 Temperature(℃) ©On-Bright Electronics Confidential -6- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch OPERATION DESCRIPTION OB2222LM is a cost effective PWM power switch optimized for off-line non-isolated buck or buckboost applications for small home appliances and linear regulator replacement. It operates in current mode and regulates output voltage with dedicated features. High integration can afford low cost and component count solution. Frequency shuffling for EMI improvement The frequency shuffling (switching frequency modulation) is implemented in OB2222LM. The oscillation frequency is modulated so that the tone energy is spread out. The spread spectrum minimizes the conduction band EMI and therefore eases the system design. Startup Current and Start up Control Startup current of OB2222LM is designed to be very low so that VDD could be charged up above UVLO threshold and starts up quickly. A large value startup resistor can therefore be used to minimize the power loss in application. Soft Start OB2222LM features an internal 256 cycles (typical) soft start to soften the electrical stress occurring in the power supply during startup. It is activated during the power on sequence. After VDD reaches UVLO(OFF), the switching frequency is gradually increased from 10KHz to 40KHz. Every restart up is followed by a soft start. Operating Current The Operating current of OB2222LM is as low as 1.5mA (typical). Good efficiency is achieved with the low operation current together with ‘Multimode’ control features. Current Sensing and Leading Edge Blanking Cycle-by-Cycle current limiting is offered in OB2222LM current mode PWM control. The switch current is detected by a sense resistor into the CS pin. An internal leading edge blanking circuit chops off the sensed voltage spike at initial internal BJT on state so that the external RC filtering on sense input is no longer needed. The PWM duty cycle is determined by the current sense input voltage and the EA output voltage. PWM operation The normal switching frequency of OB2222LM is internally fixed at 40kHz (typical). No external frequency setting components are required for PCB design simplification. Along with the increase of output current, the inductance current is up to the Vth_oc threshold. With the increase in output current, the operation frequency increases till it reaches the up limit of 65kHz (typical). The over load protection will be triggered after 10ms (typical). Base Driver The driver is a push pull stage with supply voltage VDD. It provides the driving current for the external power bipolar transistor. The sourcing current is limited to Is_max (typical 90mA). At light load or zero load condition, most of the power dissipation in a switching mode power supply is from switching loss on the BJT. The magnitude of power loss is in proportion to the switching frequency. Lower switching frequency leads to the reduction on the power loss and thus conserves the energy. The frequency reduction and burst mode operation are implemented to achieve high efficiency at light load. The minimum switching frequency is 20KHz (typical). ©On-Bright Electronics Protection Control Good power supply system reliability is achieved with its rich protection features including cycle-bycycle current limiting, output short circuit protection, FB pin open loop protection, on-chip Over Temperature Protection (OTP), VDD Over Voltage Protection (OVP), Over Loading Protection and VDD Under Voltage Lockout Protection (UVLO). Confidential -7- Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch PACKAGE MECHANICAL DATA Symbol A A1 A2 b c D E E1 e L θ ©On-Bright Electronics Dimensions In Millimeters Min Max 1.350 1.750 0.050 0.250 1.250 1.650 0.310 0.510 0.170 0.250 4.700 5.150 3.800 4.000 5.800 6.200 1.270 (BSC) 0.400 1.270 0º 8º Confidential -8- Dimensions In Inches Min Min 0.053 0.069 0.002 0.010 0.049 0.065 0.012 0.020 0.006 0.010 0.185 0.203 0.150 0.157 0.228 0.244 0.05 (BSC) 0.016 0.050 0º 8º Preliminary Datasheet OB_DOC_DS_2222LM00 OB2222LM High Precision Low Cost Power Switch 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 applications. ©On-Bright Electronics Confidential -9- Preliminary Datasheet OB_DOC_DS_2222LM00