NCP1200D100R2

NCP1200 PWM Current−Mode Controller for Low−Power Universal Off−Line Supplies Housed in SOIC−8 or PDIP−8 package, the NCP1200 represents a major leap toward ultra−compact Switchmode Power Supplies. Due to a novel concept, the circuit allows the implementation of a complete offline battery charger or a standby SMPS with few external components. Furthermore, an integrated output short−circuit protection lets the designer build an extremely low−cost AC−DC wall adapter associated with a simplified feedback scheme. With an internal structure operating at a fixed 40 kHz, 60 kHz or 100 kHz, the controller drives low gate−charge switching devices like an IGBT or a MOSFET thus requiring a very small operating power. Due to current−mode control, the NCP1200 drastically simplifies the design of reliable and cheap offline converters with extremely low acoustic generation and inherent pulse−by−pulse control. When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the skip cycle mode and provides excellent efficiency at light loads. Because this occurs at low peak current, no acoustic noise takes place. Finally, the IC is self−supplied from the DC rail, eliminating the need of an auxiliary winding. This feature ensures operation in presence of low output voltage or shorts. Features http://onsemi.com MARKING DIAGRAMS 8 SOIC−8 D SUFFIX CASE 751 1 1 8 PDIP−8 P SUFFIX CASE 626 8 1 xxx y 1 = Device Code: 40, 60 or 100 = Device Code: 4 for 40 6 for 60 1 for 100 A = Assembly Location L = Wafer Lot Y, YY = Year W, WW = Work Week G, G = Pb−Free Package 1200Pxxx AWL YYWWG 200Dy ALYW G 8 • • • • • • • • • • • • No Auxiliary Winding Operation Internal Output Short−Circuit Protection Extremely Low No−Load Standby Power Current−Mode with Skip−Cycle Capability Internal Leading Edge Blanking 250 mA Peak Current Source/Sink Capability Internally Fixed Frequency at 40 kHz, 60 kHz and 100 kHz Direct Optocoupler Connection Built−in Frequency Jittering for Lower EMI SPICE Models Available for TRANsient and AC Analysis Internal Temperature Shutdown Pb−Free Packages are Available PIN CONNECTIONS Adj FB CS GND 1 2 3 4 8 7 6 5 HV NC VCC Drv (Top View) Typical Applications • AC−DC Adapters • Offline Battery Chargers • Auxiliary/Ancillary Power Supplies (USB, Appliances, TVs, etc.) ORDERING INFORMATION See detailed ordering and shipping information in the package dimensions section on page 14 of this data sheet. © Semiconductor Components Industries, LLC, 2006 1 September, 2006 − Rev. 15 Publication Order Number: NCP1200/D NCP1200 * 1 Adj 2 FB 3 CS EMI Filter + C5 10 mF Universal Input Rsense D8 5 V1 HV 8 NC 7 VCC 6 M1 MTD1N60E D2 1N5819 6.5 V @ 600 mA + C2 470 mF/10 V Rf 470 C3 10 mF 400 V + 4 GND Drv 5 *Please refer to the application information section Figure 1. Typical Application ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ Á Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ PIN FUNCTION DESCRIPTION Pin No. 1 2 3 4 5 6 7 8 Pin Name Adj FB Function Description Adjust the Skipping Peak Current Sets the Peak Current Setpoint Current Sense Input The IC Ground Driving Pulses This pin lets you adjust the level at which the cycle skipping process takes place. By connecting an Optocoupler to this pin, the peak current setpoint is adjusted accordingly to the output power demand. CS This pin senses the primary current and routes it to the internal comparator via an L.E.B. GND Drv The driver’s output to an external MOSFET. VCC NC HV Supplies the IC No Connection This pin is connected to an external bulk capacitor of typically 10 mF. This un−connected pin ensures adequate creepage distance. Generates the VCC from the Line Connected to the high−voltage rail, this pin injects a constant current into the VCC bulk capacitor. http://onsemi.com 2 NCP1200 Adj 1 HV Current Source 75.5 k 1.4 V Skip Cycle Comparator Internal VCC UVLO High and Low Internal Regulator 8 HV + − FB 2 29 k 7 NC Current Sense 3 250 ns L.E.B. 40, 60 or 100 kHz Clock Set Q Flip−Flop DCmax = 80% Reset Q 6 VCC Ground 4 + − 8k Vref 5.2 V 60 k 1V + − ±250 mA Overload? Fault Duration 5 Drv 20 k Figure 2. Internal Circuit Architecture ÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁ Á Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁÁÁÁÁ ÁÁ ÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ Á ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ MAXIMUM RATINGS Rating Symbol VCC Value 16 Units V Power Supply Voltage Thermal Resistance Junction−to−Air, PDIP−8 version Thermal Resistance Junction−to−Air, SOIC version Maximum Junction Temperature Typical Temperature Shutdown Storage Temperature Range RqJA RqJA − 100 178 150 140 °C/W °C °C TJmax Tstg − − − − − −60 to +150 2.0 ESD Capability, HBM Model (All Pins except VCC and HV) ESD Capability, Machine Model kV V V V V 200 450 500 30 Maximum Voltage on Pin 8 (HV), pin 6 (VCC) Grounded Maximum Voltage on Pin 8 (HV), Pin 6 (VCC) Decoupled to Ground with 10 mF Minimum Operating Voltage on Pin 8 (HV) Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect device reliability. http://onsemi.com 3 NCP1200 ELECTRICAL CHARACTERISTICS (For typical values TJ = +25°C, for min/max values TJ = −25°C to +125°C, Max TJ = 150°C, VCC= 11 V unless otherwise noted) Rating DYNAMIC SELF−SUPPLY (All Frequency Versions, Otherwise Noted) VCC Increasing Level at Which the Current Source Turns−off VCC Decreasing Level at Which the Current Source Turns−on VCC Decreasing Level at Which the Latchoff Phase Ends Internal IC Consumption, No Output Load on Pin 5 Internal IC Consumption, 1 nF Output Load on Pin 5, FSW = 40 kHz Internal IC Consumption, 1 nF Output Load on Pin 5, FSW = 60 kHz Internal IC Consumption, 1 nF Output Load on Pin 5, FSW = 100 kHz Internal IC Consumption, Latchoff Phase INTERNAL CURRENT SOURCE High−voltage Current Source, VCC = 10 V High−voltage Current Source, VCC = 0 V DRIVE OUTPUT Output Voltage Rise−time @ CL = 1 nF, 10−90% of Output Signal Output Voltage Fall−time @ CL = 1 nF, 10−90% of Output Signal Source Resistance (drive = 0, Vgate = VCCHMAX − 1 V) Sink Resistance (drive = 11 V, Vgate = 1 V) CURRENT COMPARATOR (Pin 5 Un−loaded) Input Bias Current @ 1 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 kW) Oscillation Frequency, 40 kHz Version Oscillation Frequency, 60 kHz Version Oscillation Frequency, 100 kHz Version Built−in Frequency Jittering, FSW = 40 kHz Built−in Frequency Jittering, FSW = 60 kHz Built−in Frequency Jittering, FSW = 100 kHz Maximum Duty Cycle FEEDBACK SECTION (VCC = 11 V, Pin 5 Loaded by 1 kW) Internal Pullup Resistor Pin 3 to Current Setpoint Division Ratio SKIP CYCLE GENERATION Default skip mode level Pin 1 internal output impedance 1. Max value @ TJ = −25°C. 2. Max value @ TJ = 25°C, please see characterization curves. 1 1 Vskip Zout 1.1 − 1.4 25 1.6 − V kW 2 − Rup Iratio − − 8.0 4.0 − − kW − − − − − − − − fOSC fOSC fOSC fjitter fjitter fjitter Dmax 36 52 86 − − − 74 42 61 103 300 450 620 80 48 70 116 − − − 87 kHz kHz kHz Hz/V Hz/V Hz/V % 3 3 3 3 3 IIB ILimit ILskip TDEL TLEB − 0.8 − − − 0.02 0.9 350 100 230 − 1.0 − 160 − mA V mV ns ns 5 5 5 5 Tr Tf ROH ROL − − 27 5 67 28 40 12 − − 61 25 ns ns W W 8 8 IC1 IC2 2.8 − 4.0 4.9 − − mA mA 6 6 6 6 6 6 6 6 VCCOFF VCCON VCClatch ICC1 ICC2 ICC2 ICC2 ICC3 10.3 8.8 − − − − − − 11.4 9.8 6.3 710 1.2 1.4 1.9 350 12.5 11 − 880 Note 1 1.4 Note 2 1.6 Note 2 2.2 Note 2 − V V V mA mA mA mA mA Pin Symbol Min Typ Max Unit http://onsemi.com 4 NCP1200 60 50 LEAKAGE (mA) 40 30 20 10 0 −25 11.70 100 kHz 11.60 11.50 11.40 40 kHz 11.30 11.20 11.10 −25 60 kHz 0 25 50 75 100 125 VCCOFF (V) 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) Figure 3. HV Pin Leakage Current vs. Temperature Figure 4. VCC OFF vs. Temperature 9.85 100 kHz 9.80 9.75 VCCON (V) 9.70 9.65 9.60 9.55 9.50 9.45 −25 0 25 50 75 100 125 40 kHz 60 kHz 900 850 800 ICC1 (mA) 750 700 650 600 −25 60 kHz 40 kHz 0 25 50 75 100 125 100 kHz TEMPERATURE (°C) TEMPERATURE (°C) Figure 5. VCC ON vs. Temperature Figure 6. ICC1 vs. Temperature 2.10 1.90 1.70 1.50 60 kHz 1.30 40 kHz 1.10 0.90 −25 FSW (kHz) ICC2 (mA) 100 kHz 110 104 98 92 86 80 74 68 62 56 50 44 38 −25 40 kHz 0 25 50 75 100 125 60 kHz 100 kHz 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) Figure 7. ICC2 vs. Temperature Figure 8. Switching Frequency vs. TJ http://onsemi.com 5 NCP1200 6.50 6.45 400 VCCLATCHOFF (V) 6.40 ICC3 (mA) 50 75 100 6.35 6.30 6.25 220 6.20 −25 0 25 125 190 −25 0 25 50 75 100 125 370 340 310 280 250 460 430 TEMPERATURE (°C) TEMPERATURE (°C) Figure 9. VCC Latchoff vs. Temperature Figure 10. ICC3 vs. Temperature 60 CURRENT SETPOINT (V) 75 100 125 50 40 W 30 20 10 0 −25 Source 1.00 0.96 0.92 0.88 Sink 0.84 0 25 50 0.80 −25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) Figure 11. DRV Source/Sink Resistances Figure 12. Current Sense Limit vs. Temperature 1.34 1.33 1.32 Vskip (V) 1.31 1.30 1.29 1.28 −25 DUTY−MAX (%) 0 25 50 75 100 125 86.0 84.0 82.0 80.0 78.0 76.0 74.0 −25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) Figure 13. Vskip vs. Temperature Figure 14. Max Duty Cycle vs. Temperature http://onsemi.com 6 NCP1200 APPLICATIONS INFORMATION INTRODUCTION The NCP1200 implements a standard current mode architecture where the switch−off time is dictated by the peak current setpoint. This component represents the ideal candidate where low part−count is the key parameter, particularly in low−cost AC−DC adapters, auxiliary supplies etc. Due to its high−performance High−Voltage technology, the NCP1200 incorporates all the necessary components normally needed in UC384X based supplies: timing components, feedback devices, low−pass filter and self−supply. This later point emphasizes the fact that ON Semiconductor’s NCP1200 does NOT need an auxiliary winding to operate: the product is naturally supplied from the high−voltage rail and delivers a VCC to the IC. This system is called the Dynamic Self−Supply (DSS). Dynamic Self−Supply The DSS principle is based on the charge/discharge of the VCC bulk capacitor from a low level up to a higher level. We can easily describe the current source operation with a bunch of simple logical equations: POWER−ON: IF VCC < VCCOFF THEN Current Source is ON, no output pulses IF VCC decreasing > VCCON THEN Current Source is OFF, output is pulsing IF VCC increasing < VCCOFF THEN Current Source is ON, output is pulsing Typical values are: VCCOFF = 11.4 V, VCCON = 9.8 V To better understand the operational principle, Figure 15’s sketch offers the necessary light: VCCOFF = 11.4 V 10.6 V Avg. VCCON = 9.8 V VCC ON OFF Current Source Output Pulses 10.00M 30.00M 50.00M 70.00M 90.00M Figure 15. The Charge/Discharge Cycle Over a 10 mF VCC Capacitor The DSS behavior actually depends on the internal IC consumption and the MOSFET’s gate charge, Qg. If we select a MOSFET like the MTD1N60E, Qg equals 11 nC (max). With a maximum switching frequency of 48 kHz (for the P40 version), the average power necessary to drive the MOSFET (excluding the driver efficiency and neglecting various voltage drops) is: Fsw @ Qg @ V cc . 0.16 = 256 mW. If for design reasons this contribution is still too high, several solutions exist to diminish it: 1. Use a MOSFET with lower gate charge Qg 2. Connect pin through a diode (1N4007 typically) to one of the mains input. The average value on pin 8 mains PEAK. Our power contribution becomes p example drops to: 160 mW. Dstart 1N4007 2*V with Fsw = maximum switching frequency Qg = MOSFET’s gate charge VCC = VGS level applied to the gate To obtain the final driver contribution to the IC consumption, simply divide this result by VCC: Idriver = Fsw @ Qg = 530 mA. The total standby power consumption at no−load will therefore heavily rely on the internal IC consumption plus the above driving current (altered by the driver’s efficiency). Suppose that the IC is supplied from a 400 V DC line. To fully supply the integrated circuit, let’s imagine the 4 mA source is ON during 8 ms and OFF during 50 ms. The IC power contribution is therefore: 400 V . 4 mA C3 4.7 mF 400 V + 1 2 3 NCP1200 Adj FB CS HV 8 NC 7 VCC 6 EMI Filter 4 GND Drv 5 Figure 16. A simple diode naturally reduces the average voltage on pin 8 http://onsemi.com 7 NCP1200 3. Permanently force the VCC level above VCCH with an auxiliary winding. It will automatically disconnect the internal startup source and the IC will be fully self−supplied from this winding. Again, the total power drawn from the mains will significantly decrease. Make sure the auxiliary voltage never exceeds the 16 V limit. Skipping Cycle Mode The NCP1200 automatically skips switching cycles when the output power demand drops below a given level. This is accomplished by monitoring the FB pin. In normal operation, pin 2 imposes a peak current accordingly to the load value. If the load demand decreases, the internal loop asks for less peak current. When this setpoint reaches a determined level, the IC prevents the current from decreasing further down and starts to blank the output pulses: the IC enters the so−called skip cycle mode, also named controlled burst operation. The power transfer now depends upon the width of the pulse bunches (Figure 18 ). Suppose we have the following component values: Lp, primary inductance = 1 mH FSW, switching frequency = 48 kHz Ip skip = 300 mA (or 350 mV / Rsense) The theoretical power transfer is therefore: 1 @ Lp @ Ip 2 @ Fsw + 2.2 W 2 When FB is above the skip cycle threshold (1.4 V by default), the peak current cannot exceed 1 V/Rsense. When the IC enters the skip cycle mode, the peak current cannot go below Vpin1 / 4 (Figure 19). The user still has the flexibility to alter this 1.4 V by either shunting pin 1 to ground through a resistor or raising it through a resistor up to the desired level. P1 P2 P3 Figure 18. Output pulses at various power levels (X = 5 ms/div) P1