OB2263AP

OB2263 Current Mode PWM ControllerFrequency Shuffling Tone energy at below 20KHZ is minimized in the design and audio noise is eliminated during operation. OB2263 is offered in SOT23-6, SOP-8 and DIP-8 packages. GENERAL DESCRIPTION FEATURES On-Bright Proprietary Frequency Shuffling Technology for Improved EMI Performance. ■ Extended Burst Mode Control For Improved Efficiency and Minimum Standby Power Design ■ Audio Noise Free Operation ■ External Programmable PWM Switching Frequency ■ Internal Synchronized Slope Compensation ■ Low VDD Startup Current and Low Operating Current (1.4mA) ■ Leading Edge Blanking on Current Sense Input ■ Good Protection Coverage With Auto SelfRecovery o VDD Over Voltage Clamp and Under Voltage Lockout with Hysteresis (UVLO) o Gate Output Maximum Voltage Clamp (18V) o On-Bright Proprietary Line Input Compensated Cycle-by-Cycle Over-current Threshold Setting For Constant Output Power Limiting Over Universal Input Voltage Range. o Overload Protection (OLP) Ch ar mr ic h (创 裕 企 业 ) ■ APPLICATIONS Offline AC/DC flyback converter for ■ Battery Charger ■ Power Adaptor ■ Set-Top Box Power Supplies ■ Open-frame SMPS le as ed to OB2263 is a highly integrated current mode PWM control IC optimized for high performance, low standby power and cost effective offline flyback converter applications in sub 30W range. PWM switching frequency at normal operation is externally programmable and trimmed to tight range. At no load or light load condition, the IC operates in extended ‘burst mode’ to minimize switching loss. Lower standby power and higher conversion efficiency is thus achieved. VDD low startup current and low operating current contribute to a reliable power on startup design with OB2263. A large value resistor could thus be used in the startup circuit to minimize the standby power. The internal slope compensation improves system large signal stability and reduces the possible subharmonic oscillation at high PWM duty cycle output. Leading-edge blanking on current sense(CS) input removes the signal glitch due to snubber circuit diode reverse recovery and thus greatly reduces the external component count and system cost in the design. OB2263 offers complete protection coverage with automatic self-recovery feature including Cycle-byCycle current limiting (OCP), over load protection (OLP), VDD over voltage clamp and under voltage lockout (UVLO). The Gate-drive output is clamped to maximum 18V to protect the power MOSFET. Excellent EMI performance is achieved with OnBright proprietary frequency shuffling technique together with soft switching control at the totem pole gate drive output. On -B ri gh t re TYPICAL APPLICATION ©On-Bright Electronics Confidential -1- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling Part Number OB2263MP OB2263AP OB2263CP GENERAL INFORMATION Pin Configuration The OB2263 is offered in SOT23-6, DIP8 and SOP8 packages, shown as below. Description SOT23-6, Pb-free DIP8, Pb-free SOP8, Pb-free ) Package Dissipation Rating RθJA Package 企 业 (°C/W) DIP8 SOP8 SOT23-6 90 150 裕 200 le On -B ri gh t re Ordering Information 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. as ed to Ch ar mr ic h (创 Absolute Maximum Ratings Parameter Value VDD DC Supply Voltage 30 V VDD Clamp Voltage 34V VDD DC Clamp Current 10 mA VFB Input Voltage -0.3 to 7V VSENSE Input Voltage to Sense -0.3 to 7V Pin VRI Input Voltage to RI Pin -0.3 to 7V Min/Max Operating Junction -20 to 150 oC Temperature TJ Min/Max Storage Temperature -55 to 160 oC Tstg Note: Stresses beyond those listed under “absolute maximum ©On-Bright Electronics Confidential -2- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling mr ic h (创 裕 企 业 ) Marking Information TERMINAL ASSIGNMENTS I P O ar SENSE VDD GATE Ch I to RI Description Ground Feedback input pin. The PWM duty cycle is determined by voltage level into this pin and SENSE pin input. Internal Oscillator frequency setting pin. A resistor connected between RI and GND sets the PWM frequency. Current sense input pin. Connected to MOSFET current sensing resistor node. Chip DC power supply pin. Totem-pole gate drive output for the power MOSFET. ed I/O P I as Pin Name GND FB le RECOMMENDED OPERATING CONDITION Min Max 10 to 30 100 -20 to 85 gh t VDD Supply Voltage RI Resistor Value Operating Ambient Temperature Unit V Kohm o C On -B ri VDD RI TA Parameter re Symbol ©On-Bright Electronics Confidential -3- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling On -B ri gh t re le as ed to Ch ar mr ic h (创 裕 企 业 ) BLOCK DIAGRAM ©On-Bright Electronics Confidential -4- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling ESD INFORMATION Parameter Human Body Model Machine Model Test Conditions MIL-STD JEDEC-STD Min Typ 3 150 Max Min Typ Max Unit KV V Operation Current mA 8.8 9.8 V 14 15 V mr ar Ch to ΔVFB /ΔVcs Short FB pin to GND and measure current VDD = 16V, RI=100Kohm 34 V 2.0 4.8 V/V V 0.8 mA 0.75 as le re t gh On -B ri Current Sense Input(Sense Pin) T_blanking Leading edge blanking time ZSENSE_IN Input Impedance TD_OC Over Current Detection and Control Delay VTH_OC Over Current Threshold Voltage at zero Duty Cycle Oscillator FOSC Normal Oscillation Frequency uA 7.8 13 IVDD = 10 mA 20 1.4 h UVLO(ON) 3 ed VDD Under Voltage Lockout Enter UVLO(OFF) VDD Under Voltage Lockout Exit (Recovery) VDD_Clamp VDD Zener Clamp Voltage Feedback Input Section(FB Pin) AVCS PWM Input Gain VFB_Open VFB Open Loop Voltage IFB_Short FB pin short circuit current VTH_0D Zero Duty Cycle FB Threshold Voltage VTH_PL Power Limiting FB Threshold Voltage TD_PL Power limiting Debounce Time ZFB_IN Input Impedance DC_MAX Maximum Duty Cycle VDD =12.5V, RI=100K Measure Leakage current into VDD VDD=16V, RI=100Kohm, VFB=3V Unit ic I_VDD_Ops Test Conditions (创 (TA = 25OC if not otherwise noted) Symbol Parameter Supply Voltage (VDD) I_VDD_Startup VDD Start up Current 裕 ELECTRICAL CHARACTERISTICS 企 业 ) Symbol HBM MM VDD=18V, RI=100Kohm, FB=3V, CS=0 RI = 100 Kohm VDD = 16V, CS>VTH_OC, FB=3.3V V 3.7 V 35 mSec 6 75 Kohm % 300 ns 40 75 Kohm nSec FB=3.3V, RI=100 Kohm 0.70 0.75 0.80 V RI = 100 Kohm 60 65 70 KHZ ©On-Bright Electronics Confidential -5- OB_DOC_DS_63B2 OB2263 VDD = 16V, Io = -20 mA VDD = 16V, Io = 20 mA 100 2 22 0.8 10 18 VDD = 16V, CL = 1nf VDD = 16V, CL = 1nf RI=100K 220 70 -3 RI=100K 150 64 Kohm V KHZ 企 业 VDD = 16V, RI = 100Kohm % 3 V V V nSec nSec % HZ On -B ri gh t re le as ed to Ch ar Gate Drive Output VOL Output Low Level VOH Output High Level V_Clamp Output Clamp Voltage Level T_r Output Rising Time T_f Output Falling Time Frequency Shuffling Frequency ∆f_OSC Modulation range /Base frequency f_shuffling Shuffling Frequency 50 5 裕 RI_range V_RI_open Fosc_BM % (创 Frequency Voltage Stability Operating RI Range RI open load voltage Burst Mode Base Frequency 5 h ∆f_VDD VDD = 16V, RI=100Kohm, TA -20oC to 100 oC VDD = 12-25V, RI=100Kohm ic Frequency Temperature Stability mr ∆f_Temp ) Current Mode PWM ControllerFrequency Shuffling ©On-Bright Electronics Confidential -6- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling CHARACTERIZATION PLOTS VDD = 16V, RI = 100 Kohm, TA = 25oC condition applies if not otherwise noted. 20 5 0 4 3.4 3.0 6 8 10 12 14 16 VDD(V) -20 10 40 70 100 130 Temp(C) h 2 3.8 ar mr ic 0 4.2 裕 10 4.6 (创 15 企 业 5.0 ) I_VDD_startup vs. Temp I_vdd_startup (uA) Ivdd_startup(uA ) VDD Startup Current vs. Voltage VDD Operation Current vs. Load(pF) VDD UVLO and Ops Current Ch to 1.2 0.8 0.4 5 10 15 VDD (V) 20 25 50KHz 5 4 3 2 1 0 0 30 500 65KHz 100KHz 1000 1500 Gate Load (pF) 2000 re le 0 as 0 I(V D D ) (m A ) 1.6 ed I(VDD) (mA) 2 UVLO(ON) vs Temp gh 9.0 8.8 14.4 UVLO(OFF) (V) ri UVLO(ON) (V) t UVLO(OFF) vs Temp 14.5 On -B 8.6 8.4 8.2 14.3 14.2 14.1 14.0 8.0 -20 10 40 70 100 130 Temp(C) -20 10 40 70 100 130 Temp(C) ©On-Bright Electronics Confidential -7- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling 115 66 65.5 64 63.5 40 70 90 110 RI(Kohm) 130 150 -20 5 30 55 80 Temp (C) 105 130 ic Ch ar mr Vth_OC(V) vs Duty_cycle(%) 1.2 1.1 1 to 0.9 0.8 0.7 10 20 30 40 50 Duty_cycle(%) 60 70 On -B ri gh t re le as 0 ed V th_O C (V ) h 50 64.5 裕 65 65 (创 90 企 业 140 ) Fosc vs. Temp 66.5 Fosc (KHz) Fosc(K H z) Fosc(KHz) vs. RI(Kohm) ©On-Bright Electronics Confidential -8- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling OPERATION DESCRIPTION The OB2263 is a highly integrated PWM controller IC optimized for offline flyback converter applications in sub 30W power range. The extended burst mode control greatly reduces the standby power consumption and helps the design easily meet the international power conservation requirements. minimize the switching loss and reduces the standby power consumption to the greatest extend. The frequency control also eliminates the audio noise at any loading conditions. 企 业 ) • Oscillator Operation A resistor connected between RI and GND sets the constant current source to charge/discharge the internal cap and thus the PWM oscillator frequency is determined. The relationship between RI and switching frequency follows the below equation within the specified RI in Kohm range at nominal loading operational condition. (创 6500 ( Khz ) RI ( Kohm) ic h FOSC = ar mr • Current Sensing and Leading Edge Blanking Cycle-by-Cycle current limiting is offered in OB2263 current mode PWM control. The switch current is detected by a sense resistor into the sense pin. An internal leading edge blanking circuit chops off the sense voltage spike at initial MOSFET on state due to Snubber diode reverse recovery so that the external RC filtering on sense input is no longer required. The current limit comparator is disabled and thus cannot turn off the external MOSFET during the blanking period. PWM duty cycle is determined by the current sense input voltage and the FB input voltage. Ch • Operating Current The Operating current of OB2263 is low at 1.4mA. Good efficiency is achieved with OB2263 low operating current together with extended burst mode control features. 裕 • Startup Current and Start up Control Startup current of OB2263 is designed to be very low so that VDD could be charged up above UVLO threshold level and device starts up quickly. A large value startup resistor can therefore be used to minimize the power loss yet provides reliable startup in application. For AC/DC adaptor with universal input range design, a 2 MΩ, 1/8 W startup resistor could be used together with a VDD capacitor to provide a fast startup and low power dissipation solution. as ed to • Frequency shuffling for EMI improvement The frequency Shuffling/jittering (switching frequency modulation) is implemented in OB2263. The oscillation frequency is modulated with a random source so that the tone energy is spread out. The spread spectrum minimizes the conduction band EMI and therefore reduces system design challenge. le • Internal Synchronized Slope Compensation Built-in slope compensation circuit adds voltage ramp onto the current sense input voltage for PWM generation. This greatly improves the close loop stability at CCM and prevents the sub-harmonic oscillation and thus reduces the output ripple voltage. gh t re • Extended Burst Mode Operation At zero load or light load condition, majority of the power dissipation in a switching mode power supply is from switching loss on the MOSFET transistor, the core loss of the transformer and the loss on the snubber circuit. The magnitude of power loss is in proportion to the number of switching events within a fixed period of time. Reducing switching events leads to the reduction on the power loss and thus conserves the energy. OB2263 self adjusts the switching mode according to the loading condition. At from no load to light/medium load condition, the FB input drops below burst mode threshold level. Device enters Burst Mode control. The Gate drive output switches only when VDD voltage drops below a preset level and FB input is active to output an on state. Otherwise the gate drive remains at off state to On -B ri • Gate Drive OB2263 Gate is connected to an external MOSFET gate for power switch control. Too weak the gate drive strength results in higher conduction and switch loss of MOSFET while too strong gate drive output compromises the EMI. A good tradeoff is achieved through the built-in totem pole gate design with right output strength and dead time control. The low idle loss and good EMI system design is easier to achieve with this dedicated control scheme. An internal 18V clamp is added for MOSFET gate protection at higher than expected VDD input. ©On-Bright Electronics Confidential -9- OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling • Protection Controls Good power supply system reliability is achieved with its rich protection features including Cycle-byCycle current limiting (OCP), Over Load Protection (OLP) and over voltage clamp, Under Voltage Lockout on VDD (UVLO). With On-Bright Proprietary technology, the OCP threshold tracks PWM Duty cycles and is line voltage compensated to achieve constant output power limit over the universal input voltage range with recommended reference design. On -B ri gh t re le as ed to Ch ar mr ic h (创 裕 企 业 ) At overload condition when FB input voltage exceeds power limit threshold value for more than TD_PL, control circuit reacts to shut down the output power MOSFET. Device restarts when VDD voltage drops below UVLO limit. VDD is supplied by transformer auxiliary winding output. It is clamped when VDD is higher than threshold value. The power MOSFET is shut down when VDD drops below UVLO limit and device enters power on start-up sequence thereafter. ©On-Bright Electronics Confidential - 10 - OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling PACKAGE MECHANICAL DATA On -B ri gh t re le as ed to Ch ar mr ic h (创 裕 企 业 ) SOT23-6 ©On-Bright Electronics Confidential - 11 - OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling On -B ri gh t re le as ed to Ch ar mr ic h (创 裕 企 业 ) 8-Pin Plastic DIP ©On-Bright Electronics Confidential - 12 - OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling On -B ri gh t re le as ed to Ch ar mr ic h (创 裕 企 业 ) 8-Pin Plastic SOP ©On-Bright Electronics Confidential - 13 - OB_DOC_DS_63B2 OB2263 Current Mode PWM ControllerFrequency Shuffling 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. (创 裕 企 业 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. mr ic h 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. On -B ri gh t re le as ed to Ch ar 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 - 14 - OB_DOC_DS_63B2