ap3421 BCD Semiconductor Manufacturing Limited, ap3421 Datasheet
ap3421
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ap3421 Summary of contents
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... Dual 1.0A Synchronous Step-down Converters General Description The AP3421 fully integrated dual output voltage regulator. The two converters are current mode and internally compensated. The converters include integrated control and synchronous rectifier switches. The outputs are both rated for up to 1A. ...
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... Dual 1.0A Synchronous Step-down Converters Pin Configuration Figure 2. Pin Configuration of AP3421/A (Top View) Pin Description Pin Number Pin Name 1 2 AVIN PGND 6 7 Aug. 2010 Rev. 1.2 DN Package (DFN-3×3-10) Pin 1 Dot by Marking Feedback from VO2. Connect voltage divider to the FB2 load side of VO2 output inductor-capacitor filter Analog power input. Connect a 1µ ...
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... VMON threshold Feedback from VO1. Connect voltage divider to the FB1 load side of VO1 output inductor-capacitor filter Signal ground connection. Provide a star connection between this pin and PGND pin 3 Preliminary Datasheet AP3421/A Function . POR is pulled low if an output IN BCD Semiconductor Manufacturing Limited ...
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... UVLO 9 VMON REF FB1 90%REF SSC FB2 90%REF OT FB1 75mV FB2 75mV 3 PVIN 10 FB1 1 FB2 11 AGND Figure 3. Functional Block Diagram of AP3421/A Aug. 2010 Rev. 1.2 Bias UVLO Start RUN Delay SSC Fault RUN S Q Fault R REF1 90%REF Fault SSC ON1 Current Mode ...
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... Dual 1.0A Synchronous Step-down Converters Ordering Information Circuit Type A: AP3421A Blank: AP3421 Package DN: DFN-3×3-10 Temperature Package Range DFN-3×3-10 -40 to 85°C BCD Semiconductor's Pb-free products, as designated with "G1" suffix in the part number, are RoHS compliant and green. Absolute Maximum Ratings (Note 1) ...
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... Resistance AP3421A Thermal Shutdown Threshold Thermal Shutdown Hysteresis Aug. 2010 Rev. 1.2 Symbol Conditions AP3421 V IN AP3421A =1.2V CC FB1 FB2 I V =0V, V =5.0V SHDN E/S IN AP3421 V Rising Edge UVLO AP3421A V HUVLO V V Falling VMON_POR VMON V V FB1, FB2 I LIM1 I LIM2 OSC1 OSC2 t ...
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... Aug. 2010 Rev. 1.2 0.66 0.64 0.62 0.60 0.58 0.56 0.54 0.52 0.50 0.48 -60 -40 5.2 5.4 5.6 5.8 Figure 5. Supply Current vs. Temperature 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 100 120 140 -60 -40 Figure 7. Current Limit 2 vs. Temperature BCD Semiconductor Manufacturing Limited 7 Preliminary Datasheet AP3421/A =25°C, unless =1.2V FB1 FB2 - 100 120 o Temperature ( C) - 100 120 O Temperature ( C) 140 140 ...
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... V =2. 1000 1200 200 Figure 11. VO2 Efficiency vs. Output Current 8 Preliminary Datasheet AP3421/A =25°C, unless A V =2.5V 200 400 600 800 1000 1200 Output Current (mA) V =1.2V O2 400 600 800 1000 1200 Output Current (mA) ...
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... Aug. 2010 Rev. 1.2 Preliminary Datasheet V 01 2V/div V O2 1V/div V IN 5V/div V POR 5V/div Time 400µs/div Figure 13. Power-down from VIN I O2 500mA/div V (AC) O2 50mV/div Time 100µs/div Figure 15. Load Transient (V =1.2V I =0.5A to 1.0A BCD Semiconductor Manufacturing Limited 9 AP3421/A =25°C, unless A ...
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... Output 1 Induction Current 1A/div V IN 5V/div Output 2 Induction Current 1A/div Time 40µs/div Figure 17. Short Protection for Output 2V/div V O1 2V/div V O2 2V/div Output 2 Induction Current 1A/div Time 10ms/div Figure 19. Output 2 Short Recovery BCD Semiconductor Manufacturing Limited 10 AP3421/A =25°C, unless A ...
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... Enable/Synchronization function. Pulling this pin high statically enables the AP3421/A while pulling the pin low statically for longer than 4µs will shut down the AP3421/A. Applying a pulse to this pin will synchronize SW1 and SW2 switching frequency to ½ the external clock frequency. The external frequency lock-in ranges from 1 ...
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... Dual 1.0A Synchronous Step-down Converters Typical Application V = OFF ON L1 3.3 V =2. 30.1k 20k Figure 20. Typical Application Circuit of AP3421 (Note 2) Aug. 2010 Rev. 1.2 C1' 84. 4.7k 24.9k PVIN AVIN VMON POR E/S L2 3.3 AGND SW1 SW2 FB1 FB2 10 F PGND BCD Semiconductor Manufacturing Limited 12 Preliminary Datasheet ...
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... 30.1k 20k Figure 21. Typical Application Circuit of AP3421A (Note 2) Note 2: AVIN and PVIN pin should not be connected together directly to avoid disturbance between them in PCB layout: 1) Place a 1.0µF capacitor between AVIN pin and AGND for power filtering. 2) Place a 10µF capacitor between PVIN pin and PGND for power filtering. ...
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... Dual 1.0A Synchronous Step-down Converters Mechanical Dimensions Aug. 2010 Rev. 1.2 DFN-3×3-10 BCD Semiconductor Manufacturing Limited 14 Preliminary Datasheet AP3421/A Unit: mm(inch) ...
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... BCD Semiconductor Manufacturing Limited does not convey any license under its patent rights or of any its products or circuits. BCD Semiconductor Manufacturing Limited does not convey any license under its patent rights or other rights nor the rights of others. ...