DPA424 Power Integrations, Inc., DPA424 Datasheet
DPA424
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DPA424 Summary of contents
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... V IN Figure 1. Typical Forward Converter Application. Total Device Dissipation PRODUCT DPA423R DPA424R DPA425R DPA426R Table 1. Notes: 1. Maximum output power is limited by device internal current limit. This is either peak output power or continuous power if adequate heat sinking is provided to keep T assume worst case R forward converter configuration with diode rectification higher output power possible using synchronous rectification ...
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DPA423-426 Functional Block Diagram ......................................................................................................................................... 3 Pin Functional Description ........................................................................................................................................ 3 DPA-Switch Family Functional Description .............................................................................................................. 4 CONTROL (C) Pin Operation ................................................................................................................................. 4 Oscillator and Switching Frequency ....................................................................................................................... 5 Pulse Width Modulator & Maximum Duty Cycle ..................................................................................................... 6 Minimum Duty ...
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V C CONTROL ( SHUNT REGULATOR/ ERROR AMPLIFIER - + 5 (LIMIT) CURRENT LIMIT START ADJUST ON/OFF EXTERNAL CURRENT LIMIT ( LINE-SENSE ( OV/UV ...
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DPA423-426 DPA-Switch Family Functional Description DPA-Switch is an integrated switched mode power supply chip that converts a current at the control input to a duty cycle at the open drain output of a high voltage power MOSFET. During normal operation ...
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MOSFET from zero to the maximum value over approximately 5 ms. The high voltage current source is turned off at the end of the soft-start external feedback/ supply current is fed into the CONTROL ...
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DPA423-426 Pulse Width Modulator and Maximum Duty Cycle The pulse width modulator implements voltage mode control by driving the output MOSFET with a duty cycle inversely proportional to the current into the CONTROL pin that is in excess of the ...
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CONTROL pin voltage reaches 5.8.V. If the power supply loses regulation before reaching the UV lower threshold, the device will enter auto-restart. At the end of each auto-restart cycle (S7), the UV comparator is ...
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DPA423-426 (typical), the CONTROL pin goes into the hysteretic mode of operation. In this mode, the CONTROL pin goes through alternate charge and discharge cycles between 4.8 V and 5.8 V (see CONTROL Pin Operation section above) and the IC ...
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Using Feature Pins FREQUENCY (F) Pin Operation The FREQUENCY pin is a digital input pin. Shorting the FREQUENCY pin to SOURCE pin selects the nominal switching frequency of 400 kHz (Figure 9) which is suited for most applications. For other ...
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DPA423-426 (Enabled) Output MOSFET Switching (Disabled) I (Default) LIMIT Current Limit -21.5 µA -25.5 µ Pin Voltage -250 -200 -150 -100 X Pin Current (µA) Note: These figures provide idealized functional characteristics with typical performance values. Please ...
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CONTROL Pin EXTERNAL CURRENT LIMIT (X) LINE-SENSE (L) Figure 8. LINE-SENSE (L), and EXTERNAL CURRENT LIMIT (X) Pin Input Simplified Schematic. DPA-Switch 230 µA (Negative Current Sense - ON/OFF, Current Limit Adjustment (Voltage Sense) 1 ...
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DPA423-426 Typical Uses of FREQUENCY (F) Pin + DC D Input CONTROL Voltage Figure 9. 400 kHz Frequency Operation. Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins + DC Input Voltage D L CONTROL ...
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Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins (cont Input CONTROL Voltage Figure 15. Externally Set Current Limit output or can be replaced by a manual ...
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DPA423-426 Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins (cont.) + 619 kΩ Input CONTROL Voltage Figure 21. Active-on Remote ON/OFF with LINE-SENSE and EXTERNAL CURRENT ...
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... V requiring any other circuit changes. This has been used here to replace the DPA424R with a DPA425R. The selectable 300/400 kHz switching frequency is set to 300 kHz by connecting the FREQUENCY (F) pin to CONTROL (C). DRAIN voltage clamping is provided by VR1, which keeps the peak DRAIN voltage within acceptable limits. Transformer core reset is provided by the gate capacitance of Q1 with R17 in series ...
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... Each table specifies the input voltage range and assumes a single 5 V output using Schottky diode rectification. For example, referring to Table 1, a DPA424R would typically dissipate converter and has a maximum power capacity the same converter the DPA425R would dissipate 0 ...
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DPA-Switch may be used for lower power applications where higher efficiency is needed or minimal heat sinking is available. Generally, selecting the next larger device, than is required for power delivery will give the highest efficiency. ...
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DPA423-426 as close as possible between SOURCE and CONTROL pins for better noise immunity. The feedback optocoupler output should also be located close to the CONTROL and SOURCE pins of DPA-Switch. Heat Sinking To maximize heat sinking of the DPA-Switch ...
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Solder Side Component Side TOP VIEW V + DPA-Switch - Maximize hatched copper area for optimum heat sinking Via between board layers V Figure 26. Layout Considerations for DPA-Switch using R Package. Transformer Opto- ...
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... DPA423-426 DRAIN Voltage ............................................ -0.3 to 220 V DRAIN Peak Current: DPA423 ............................... 1.75 A DPA424 ................................. 3.5 A DPA425 .................................... 7 A DPA426 ................................. 9.6 A CONTROL Voltage .......................................... -0 CONTROL Current ............................................... 100 mA LINE SENSE Pin Voltage ................................ -0 EXTERNAL CURRENT LIMIT Pin Voltage .. -0 FREQUENCY Pin Voltage ............................... -0 Thermal Impedance: R Package (θ ) ............... 40 °C/W JA ........................................................................... 30 °C/W (θ ...
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Parameter Symbol CONTROL FUNCTIONS (cont.) PWM Gain DC reg PWM Gain Temperature Drift Dynamic Z Impedance C Dynamic Impedance Temperature Drift CONTROL Pin Internal Filter Pole SHUTDOWN/AUTO-RESTART CONTROL Pin I C(CH) Charging Current Charging Current Temperature Drift Auto-restart Upper V ...
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DPA423-426 Parameter Symbol LINE-SENSE (L) AND EXTERNAL CURRENT LIMIT (X) INPUTS (cont) Line Overvoltage or Remote ON/ I OFF Threshold OV Current and Hysteresis (L pin) Remote ON/OFF Negative Thresh- I REM old Current and Hysteresis (X pin) L pin ...
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... OUTPUT On-State R Resistance DS(ON) Conditions (Unless Otherwise Specified) See Figure 30 ; SOURCE = -40 to 125 ° DPA423 di/dt = 300 mA/µs DPA424 di/dt = 600 mA/µ °C J DPA425 di/dt = 1.25 A/µs DPA426 di/dt = 1.75 A/µ ° )/2 C C(skip °C DPA423 ...
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... See Note )/ °C C C(skip )/2 C C(skip) B DPA423 Output MOSFET Enabled DPA424 DPA425 400 kHz DPA426 OSC Output MOSFET Disabled 400 kHz L OSC specification by ramping the DRAIN pin voltage up to DSS . Min Typ ...
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VOLTAGE Figure 27. Duty Cycle Measurement. 120 100 Dynamic 1 = Impedance Slope CONTROL Pin Voltage (V) Figure 28. CONTROL Pin I-V Characteristic 470 Ω 0-15 V NOTE: This ...
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DPA423-426 BENCH TEST PRECAUTIONS FOR EVALUATION OF ELECTRICAL CHARACTERISTICS The following precautions should be followed when testing DPA-Switch by itself outside of a power supply. The schematic shown in Figure 30 is suggested for laboratory testing of DPA-Switch. When the ...
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Typical Performance Characteristics (cont.) 1.2 1.0 0.8 0.6 0.4 0.2 0 -50 - 100 125 150 Junction Temperature (°C) Figure 33. Frequency vs. Temperature. 1.2 1.0 0.8 0.6 0.4 0.2 0 -50 - ...
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DPA423-426 Typical Performance Characteristics (cont.) 1 1.375 - I x 843 kΩ 1.4 ≤ ≤ -200 µA I -25 µA X 1.2 1.0 0.8 0.6 0.4 0.2 0 -225 -175 -125 -250 -200 -150 -100 EXTERNAL ...
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... Figure 46. On-resistance vs. Temperature. 2.5 Data taken from a typical 2 forward converter design. 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 In-Circuit Peak Drain Current Normalized to Nominal Device Internal Current Limit Figure 48. Typical Switching Loss. DPA423-426 100 125 150 Temperature (C) Scaling Factors: DPA423 = 0.08 DPA424 = 0.20 DPA425 = 0.55 DPA426 = 1. 5/03 ...
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DPA423-426 PART ORDERING INFORMATION DPA 423 .390 (9.91) .420 (10.67) .055 (1.40) .066 (1.68) .326 (8.28) .336 (8.53) .208 (5.28) Ref .024 (0.61) .034 (0.86) .315 (8.00) .380 (9.65) .638 (16.21) .050 (1.27) .038 (0.97) ...
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DPA423-426 J 31 5/03 ...
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... A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness. The PI logo, TOPSwitch , TinySwitch , LinkSwitch and EcoSmart are registered trademarks of Power Integrations, Inc. PI Expert and DPA-Switch are trademarks of Power Integrations, Inc. ©Copyright 2003, Power Integrations, Inc. ...