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Details, datasheet, quote on part number:NCP1002
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Datasheet text preview:
AND8019/D Offline Converter Provides 5.0 Volt, 1.0 Amp Output for Small Electronic Equipment
Prepared by: Alan Ball ON Semiconductor http://onsemi.com
APPLICATION NOTE
General Description ON Semiconductor's NCP1000 series of offline converters offers a low cost, high efficiency power source for low power, electronic equipment. It serves the same function as small, line frequency transformers, but with the added benefits of line and load regulation, transient suppression, reduction in weight, and operation across the universal input voltage range. This kit provides a 5.0 volt, 1.0 amp output, which is derived from an input source of 85 to 265 VAC, and 50 Hz to 60 Hz. This range of input voltages will allow this circuit to function virtually anywhere in the world without modification. The output is regulated and current limited. Both common mode and differential mode EMI filtering are incorporated on the ac line.
Features
Cap, ceramic, 1.0 mF, 10 V, 0603 TDK Cap, ceramic, .01 mF, 50 V, 0603 TDK Cap, Alum elect, 10 mF, 25 V Panasonic Cap, Alum elect, 1500 mF, 6.3 V Panasonic Cap, class X1, 1.0 nF, 440 Vac Vishay/Roederstein Diode, Rectifier, 600 V, 1.0 A ON Semiconductor Rectifier, Schottky, 40 V, 3.0 A ON Semiconductor Diode, Switching, 70 V, 200 mA ON Semiconductor Diode, UltraFast 600 V, 1.0 A, ON Semiconductor Fuse, 160 mA, 250 Vac Cooper Bussman Inductor, 33 mH Cooper Coiltronics Connector Beau Resistor, 470 W, 5% Vishay/Dale Resistor, 4.7 kW, .25 W, 5% Resistor, 270 W, 5% Vishay/Dale Resistor, 2.0 kW, 5% Vishay/Dale Resistor, 6.8 W, .25 W, 5% Part Number ECQU2A823MV EEUEB2W100 ECKD3A222KBP ECEA1EKK3R3 Reference C1 C2, C3 C4 C5 Resistor, 10 W, .25 W, 5% Transformer, flyback Cooper Coiltronics IC, Switching Regulator ON Semiconductor Optocoupler Lumex IC, Voltage Regulator ON Semiconductor C1608X5R1A105K C1608X7R1A103K ECA1EM100 EEUFCOJ152 WYO102MCMBFOK 1N4005 MBRS340T3 MMBD6050LT1 MUR160 BK/ETF160MA UP0.4C330 830502 CRCW12064715% CRCW12062715% CRCW12062k1% CTX1314602 NCP1000P 6715605 TL431AID C6 C7, C11 C8 C9, C10 C12 D1D4 D5 D6 D7 F1 L1 P1, P2 R1 R2 R3 R4, R5 R6, R7 R8, R9 T1 U1 U2 U3
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Output Well Regulated Over Changes in Line and Load Minimal Parts Count Universal Input Voltage Range 100 kHz Switching Frequency Power Switch and Current Sense Built into Chip No External Startup Circuit Required Thermal Shutdown Circuitry Included Board Designed for EMI and UL Approvals
Description / Manufacturer
Parts List
Cap, xseries, .082 mF, 250 Vac Panasonic Cap, Alum elect, 10 mF, 450 V Panasonic Cap, ceramic, 2.2 pF, 1000 Vac Panasonic Cap, Alum elect, 3.3 mF, 25 V Panasonic
© Semiconductor Components Industries, LLC, 2002
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June, 2002 Rev. 4
Publication Order Number: AND8019/D
AND8019/D
Manufacturers Contact Data
Mfr. ON Semiconductor Cooper Electronics TDK Mallory Vishay/... Lumex Beau Interconnect Panasonic Phone Web 800 2829855 www.onsemi.com 561 7525000 www.cooperet.com 847 8036100 www.component.tdk.com
Board Evaluation The following Power Supply Test Setup diagram and description is designed to allow the board to be tested for all parameters listed in the Converter Test Data table. This may be used to confirm proper operation of the board, as well as operating parameters of modified boards.
317 2730090 www.naccdoesit.com 818 7811642 www.vishay.com/index.html 847 3592790 www.lumex.com 603 5245101 www.beauint.com www.panasonic.com
1A Scope 500 mA 90 mA 85 vac265 vac 50 Hz60 Hz V Volt or Watt Meter UUT 55 W 12 W 10 W
Load Fixture
Figure 1. Power Supply Test Setup
Test Setup The input power source needs to be variable over the range of voltages and frequencies that you choose to test. This can be either a variac or an electronic power source. Connect it to a voltmeter or wattmeter. A wattmeter will be required to measure efficiency. If none is available, use a voltmeter. The output of the meter will be fed into the input connector on the board. The polarity is not important as this converter has an isolated output. Please keep in mind that the input side of this circuit is hot including the ground. The output connector should be connected to an ammeter in the high line, and then to a set of load resistors. The 12 W and 10 W resistors should be rated at 10 watts, and the 55 W at 2.0 watts. Any lab scope with at least a 20 MHz bandwidth will be adequate to observe ripple and switching waveforms. The unit will not be damaged by input voltages below 85 volts, but may not operate properly. Do not exceed the 265 volt rating as this could damage the NCP1000 as well as other components.
Measurement Techniques To accurately measure the output voltage and ripple, the voltmeter and oscilloscope probes should be connected as close as possible to the output terminals of the board. Measuring the output voltage at the load resistors will result in errors due to the impedance of the ammeter and of the lead wires. Ripple measurements often contain large amounts of common mode noise. Before taking measurements, connect the scope probe to the ground lead at the negative output terminal. Any spikes that are on the screen of the scope are common mode noise that is being picked up by the scope leads, and are not part of the output ripple. This phenomenon may be reduced by using two scope probes in a differential measurement mode. Connect both ground leads to the negative output terminal. Connect one scope probe to the negative terminal also, and the other to the positive terminal. Set the scope up to subtract the ground signal from the ripple signal, and the resulting waveform will be a more accurate representation of the ripple.
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AND8019/D
Regulation Converter Test Data
Parameter Line Regulation Load Regulation Combined Line/ Load Regulation Output Ripple Input Power Power Factor Efficiency Conditions 85 V Vin 265 V 0 A Io 1.0 A 85 V Vin 265 V 0 A Io 1.0 A Io = 1.0 A Vin = 115 V, Io = 1.0 A Vin = 220 V, Io = 1.0 A Vin = 115 V, Io = 1.0 A Vin = 220 V, Io = 1.0 A Vin = 115 V, Io = 1.0 A Vin = 220 V, Io = 1.0 A Data DVo = 6.0 mV DVo = 8.0 mV DVo = 10 mV 100 mVpp 7.75 watts 7.88 watts 0.57 0.49 h = 66% h = 64%
To measure line regulation, hold the load constant and vary the input over the desired range taking measurements at convenient intervals. The change in output voltage for a fixed load, across the range of input voltages is the line regulation. Load regulation is measured in a similar manner. The line is held constant and the output voltage is measured as the load is varied from minimum to maximum.
Ripple
The scope should be connected as described in the Measurement Techniques section, and should be ac coupled. Peaktopeak ripple is the measurement from the lowest point to the highest point on the trace. If a peaktomean measurement is desired, set the scope input to ground, move the trace on top of the center graticule line of the scope, and then set the scope coupling back to ac. The voltage from the lowest point on the trace and the highest point on the trace, to the center graticule line are the peaktomean measurements.
Efficiency
Troubleshooting
Symptom Unit does not turn on, does not draw current Solution 1. Assure that ac source and meter are properly connected by measuring the voltage at the input connector. 2. Measure the voltage across C2. If it is not approximately equal to the peak input voltage, check for wrong or defective components (R6, R7, D1D4). 3. Observe voltage at pin 1 of U1. This voltage needs to exceed 8.5 volts for unit to start, and remain greater than 7.5 volts for unit to operate. If not in this range check for shorts, and assure that pin 5 is greater than 50 volts, otherwise replace chip. 4. Measure the voltage at pin 2 of U1. It should measure less than 4.5 volts for PWM to be active. If it is, and the output is not switching, the NCP1000 may be defective. 1. Check for obvious shorts on the board and remove if found. 2. Disconnect all leads and measure resistance across C2. If no short is found, check test setup. If a short is found, isolate it by removing components and testing (D1D4, C2, U1).
1. Assure that the input voltage and output current are in the specified ranges. 2. Measure voltage across C8. It should be at least twice the output voltage. If not, check D6, L2 and C8. 3. Check the voltage at pin 2. If it is greater than 4.5 volts the opto may be shorted, if 0 the opto may open or C4 may be shorted. 4. Measure voltage at pin 8 of U3 and measure voltage drop across R3. If:
Efficiency is defined as:
h = Pout/Pin = (Vo Io) / Pin
The output power is the output voltage multiplied by the output current. The input power must be read from a quality wattmeter with a wide bandwidth due to the harmonic content of the input current waveform. There is no accurate method of measuring the input power by the use of DVM's or oscilloscopes. Most wattmeters will also measure power factor, line voltage and line current.
Transient Loads
Rapid changes in the load of a power converter cause the output voltage to increase or decrease for a short period of time. If the circuit that will be attached to this converter is sensitive to small excursions in voltage, it is highly recommended to test the unit under similar transients. The following exercise will test the unit for a transient from 250 mA to 1.0 A and from 1.0 A to 250 mA. If the actual load transient is different, the loads should be modified to reflect those conditions. Response to load transients can be observed by causing a step load change and synching the oscilloscope to this event. The best way to do this is to replace the switch on the 500 mA load (10 W resistor) with a FET. An ON Semiconductor MTD3302 transistor, driven by a pulse generator with a 0 volt to 10 volt pulse will make a simple electronic switch. Figures 8 and 9 show the transient response to an output load change of 10% to 100% load. Observing the output voltage on an oscilloscope during this event will allow measurement of the level of perturbation as well as the duration.
Unit does not turn on, draws excessive current
· Unit does
not regulate
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V8 0 then replace U3. V8 > 2.5 volts & VR3 = 0 then replace U3. V8 > 2.5 volts & VR3 > 0 then replace U2.
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