Enhanced PWM Current-Mode Controller

NCP1217, NCP1217A Enhanced PWM Current−Mode Controller for High−Power Universal Off−Line Supplies Housed in an SO−8 or PDIP−7 package, the NCP1217 represents the enhanced version of the NCP1203−based controllers. Thanks to its high drive capability, NCP1217 drives large gate−charge MOSFETs, which together with internal ramp compensation and built−in overvoltage protection, ease the design of modern AC/DC adapters. NCP1217 offers a true alternative to UC384X−based designs. With an internal structure operating at different fixed frequencies (65–100–133 kHz), the controller features a high−voltage startup FET, which ensures a clean and loss less startup sequence. Its current−mode control topology provides an excellent input audio−susceptibility and inherent pulse−by−pulse control. Internal ramp compensation easily prevents subharmonic oscillations from taking place in continuous conduction mode designs. When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the so−called skip cycle mode and provides excellent efficiency at light loads. Because this occurs at a user adjustable low peak current, no acoustic noise takes place. The NCP1217 features two efficient protective circuitries: 1) In presence of an overcurrent condition, the output pulses are disabled and the device enters a safe burst mode, trying to restart. Once the default has gone, the device auto−recovers. 2) If an external signal www.DataSheet4U.com (e.g. a temperature sensor) pulls Pin 1 above 3.2 V, output pulses are immediately stopped and the NCP1217 stays latched in this position. Reset occurs when the VCC collapses to ground, e.g. the user unplugs the power supply. Features http://onsemi.com MARKING DIAGRAMS 8 8 1 SOIC−8 D1, D2 SUFFIX CASE 751 1 17xxx ALYW G PDIP−8 N SUFFIX CASE 626 8 1 1 P1217xxxx AWL YYWWG • • • • • • • • • • • • • • • • • • Current−Mode with Adjustable Skip−Cycle Capability Built−in Internal Ramp Compensation Auto−Recovery Internal Output Short−Circuit Protection Internal 1.0 ms Soft−Start (NCP1217A Only) Limited Duty−Cycle to 50% (NCP1217A Only) Full Latchoff if Adjustment Pin is Brought High Extremely Low No−Load Standby Power Internal Temperature Shutdown 500 mA Peak Current Capability Fixed Frequency Versions at 65 kHz, 100 kHz and 133 kHz Direct Optocoupler Connection Internal Leading Edge Blanking SPICE Models Available for TRANsient and AC Analysis Pb−Free Packages are Available High Power AC/DC Converters for TVs, Set−Top Boxes, etc. Offline Adapters for Notebooks Telecom DC−DC Converters All Power Supplies xxxx A L, WL Y, YY W, WW G or G = = = = = = Specific Device Code Assembly Location Wafer Lot Year Work Week Pb−Free Package PIN CONNECTIONS Adj 1 FB 2 8 7 6 5 (Top View) HV NC VCC Drv CS 3 GND 4 DEVICE MARKING INFORMATION See detailed device marking information in the ordering information section on page 16 of this data sheet. Typical Applications ORDERING INFORMATION See detailed ordering and shipping information in the ordering information section on page 16 of this data sheet. © Semiconductor Components Industries, LLC, 2005 1 September, 2005 − Rev. 4 Publication Order Number: NCP1217/D NCP1217, NCP1217A See Application Section + NCP1217 1 2 EMI FILTER UNIVERSAL INPUT 3 4 Adj FB CS VCC Gnd Drv HV 8 7 6 5 Aux. VOUT + Ramp Adjustment + Figure 1. Typical Application Example ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ PIN FUNCTION DESCRIPTION Pin No. 1 Pin Name Adj Function Description Adjust the skipping peak current This pin lets you adjust the level at which the cycle skipping process takes place. Shorting this pin to ground permanently disables the skip cycle feature. By bringing this pin above 3.1 V, you permanently shut off the device. By connecting an optocoupler to this pin, the peak current setpoint is adjusted accordingly to the output power demand. This pin senses the primary current and routes it to the internal comparator via an L.E.B. By inserting a resistor in series with the pin, you control the amount of ramp compensation you need. − The driver’s output to an external MOSFET. This pin is connected to an external bulk capacitor of typically 22 mF. − Ensures a clean and lossless startup sequence This unconnected pin ensures adequate creepage distance. Connected to the high−voltage rail, this pin injects a constant current into the VCC capacitor during the startup sequence. 2 3 FB CS Sets the peak current setpoint Current sense input 4 5 6 7 8 Gnd Drv VCC NC HV The IC ground Driving pulses Supplies the IC http://onsemi.com 2 NCP1217, NCP1217A Adj 1 + − + − Latchoff Comparator HV 8 HV Current Source 3.1 V Set Reset Latch UVLO FB 2 80 k 1.1 V + − Skip Cycle Comparator UVLO High and Low Internal VCC NC 7 24 k Current Sense 3 250 ns L.E.B. 19 k Ramp Compensation 20 k Ground 4 + − VREF 57 k + − Drv 25 k 1V 1ms SS* ±500 mA 5 65−100−133 kHz Clock Set Reset Q Flip−Flop DCmax = 74% Reset VCC Q Overload Management 6 * Available for “A” version only Figure 2. Internal Circuit Architecture ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ MAXIMUM RATINGS Rating Symbol VCC − Value 16 Unit V V V V mA °C/W °C/W °C °C °C °C kV V Power Supply Voltage Power Supply Voltage on All Other Pins Except Pin 8 (HV), Pin 6 (VCC) and Pin 5 (Drv) Maximum Voltage on Pin 8 (HV), Pin 6 (VCC) Decoupled to Ground with 10 mF Maximum Voltage on Pin 8 (HV), Pin 6 (VCC) Grounded Maximum Current into All Pins Except VCC (6) and HV (8) when 10 V ESD Diodes are Activated Thermal Resistance, Junction−to−Case Thermal Resistance, Junction−to−Air, PDIP−7 Version Thermal Resistance, Junction−to−Air, SO−8 Version Maximum Junction Temperature Temperature Shutdown Hysteresis in Shutdown Storage Temperature Range ESD Capability, HBM Model (All Pins Except VCC and HV) ESD Capability, Machine Model −0.3 to 10 500 450 5.0 57 100 178 150 155 30 −60 to +150 2.0 200 VHV VHV − RqJC RqJA RqJA TJMAX − − − − − Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected. http://onsemi.com 3 NCP1217, NCP1217A ELECTRICAL CHARACTERISTICS (For typical values TJ = 25°C, for min/max values TJ = 0°C to +125°C, Max TJ = 150°C, VCC = 11 V unless otherwise noted.) Characteristic SUPPLY SECTION (All frequency versions, unless otherwise noted) Turn−On Threshold Level, VCC Going Up Minimum Operating Voltage After Turn−On VCC Decreasing Level at which the Latchoff Phase Ends Internal IC Consumption, No Output Load on Pin 5, FSW = 65 kHz Internal IC Consumption, No Output Load on Pin 5, FSW = 100 kHz Internal IC Consumption, No Output Load on Pin 5, FSW = 133 kHz Internal IC Consumption, 1.0 nF Output Load on Pin 5, FSW = 65 kHz Internal IC Consumption, 1.0 nF Output Load on Pin 5, FSW = 100 kHz Internal IC Consumption, 1.0 nF Output Load on Pin 5, FSW = 133 kHz Internal IC Consumption, Latchoff Phase, VCC = 6.0 V INTERNAL STARTUP CURRENT SOURCE (TJ u 0°C) High−Voltage Current Source, VCC = 10 V High−Voltage Current Source, VCC = 0 DRIVE OUTPUT Output Voltage Rise−Time @ CL = 1.0 nF, 10−90% of a 12 V Output Signal Output Voltage Fall−Time @ CL = 1.0 nF, 10−90% of a 12 V Output Signal Source Resistance Sink Resistance CURRENT COMPARATOR (Pin 5 Unloaded) Input Bias Current @ 1.0 V Input Level on Pin 3 Maximum Internal Current Setpoint Default Internal Current Setpoint for Skip Cycle Operation Propagation Delay from Current Detection to Gate OFF State Leading Edge Blanking Duration INTERNAL OSCILLATOR (VCC = 11 V, Pin 5 Loaded by 1.0 kW) Oscillation Frequency, 65 kHz Version Oscillation Frequency, 100 kHz Version Oscillation Frequency, 133 kHz Version Maximum Duty−Cycle, NCP1217 Maximum Duty−Cycle, NCP1217A 1. Maximum Value @ TJ = 0°C. 2. Minimum Value @ TJ = 125°C. − − − − − fOSC fOSC fOSC Dmax Dmax 58.5 90 120 69 42 65 100 133 74 46.5 71.5 110 146 80 50 kHz kHz kHz % % 3 3 3 3 3 IIB ILimit ILskip TDEL TLEB − 0.9 − − − 0.02 1.0 330 90 250 − 1.1 − 150 − mA V mV ns ns 5 5 5 5 Tr Tf ROH ROL − − 15 5.0 60 20 20 10 − − 35 18 ns ns W W 8 8 IC1 IC2 3.5 (Note 2) − 6.0 7.0 7.8 − mA mA 6 6 6 6 6 6 6 6 6 6 VCCON VCCmin VCClatch ICC1 ICC1 ICC1 ICC2 ICC2 ICC2 ICC3 11.8 6.9 − − − − − − − − 12.8 7.6 5.6 960 1020 1060 1.7 2.1 2.4 230 13.8 8.3 − 1110 (Note 1) 1180 (Note 1) 1200 (Note 1) 2.0 (Note 1) 2.4 (Note 1) 2.9 (Note 1) − V V V mA mA mA mA mA mA mA Pin Symbol Min Typ Max Unit http://onsemi.com 4 NCP1217, NCP1217A ELECTRICAL CHARACTERISTICS (continued) (For typical values TJ = 25°C, for min/max values TJ = 0°C to +125°C, Max TJ = 150°C, VCC = 11 V unless otherwise noted.) Characteristic FEEDBACK SECTION (VCC = 11 V, Pin 5 Loaded by 1.0 kW) Internal Pull−Up Resistor Pin 2 (FB) to Internal Current Setpoint Division Ratio SKIP CYCLE GENERATION Default Skip Mode Level Pin 1 Internal Output Impedance INTERNAL RAMP COMPENSATION Internal Ramp Level @ 25°C (Note 3) Internal Ramp Resistance to CS Pin ADJUSTMENT LATCHOFF LEVEL Latching Level 3. A 1.0 MW resistor is connected to the ground for the m