NCP1587 ONSEMI [ON Semiconductor], NCP1587 Datasheet
NCP1587
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NCP1587 Summary of contents
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... V. These 8−pin devices provide an optimal level of integration to reduce size and cost of the power supply. The NCP1587/A provide gate driver design and an internally set 275 kHz (NCP1587) and 200 kHz (NCP1587A) oscillator. In addition to the 1 A gate drive capability, other efficiency enhancing features of the gate driver include adaptive non− ...
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0 REF COMP/DIS 3 BST FB COMP/DIS TG PHASE BG GND Figure 1. Typical Application Diagram POR UVLO FAULT LATCH FAULT + R PWM - Q ...
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... Rating Thermal Resistance, Junction−to−Ambient Thermal Resistance, Junction−to−Case NCP1587A Operating Junction Temperature Range NCP1587A Operating Ambient Temperature Range Storage Temperature Range Lead Temperature Soldering (10 sec): Reflow (SMD styles only) Pb−Free Moisture Sensitivity Level Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the Recommended Operating Conditions is not implied ...
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... V Under Voltage Lockout UVLO Threshold UVLO Hysteresis Switching Regulator VFB Feedback Voltage, Control Loop in Regulation Oscillator Frequency NCP1587 NCP1587A Ramp−Amplitude Voltage Minimum Duty Cycle Maximum Duty Cycle Error Amplifier (GM) Transconductance Open Loop DC Gain Output Source Current Output Sink Current Input Bias Current Soft− ...
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TYPICAL CHARACTERISTICS 5.0 4.7 4.4 4.1 3.8 3 JUNCTION TEMPERATURE (°C) J Figure 3. I vs. Temperature JUNCTION ...
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... The devices can achieve an 80% duty cycle. There is a built in off−time which ensures that the bootstrap supply is charged every cycle. Both parts can allow 0.8 V conversion at 275 kHz (NCP1587) and 200 kHz (NCP1587A). Input Voltage Range (V and BST) ...
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... Undervoltage Lockout (UVLO) is provided to ensure that unexpected behavior does not occur when V support the internal rails and power the converter. For the NCP1587/A, the UVLO is set to permit operation when converting from a 5.0 input voltage. Overcurrent Threshold Setting NCP1587/A can easily program an Overcurrent Threshold ranging from 550 mV, simply by adding a resistor (RSET) between BG and GND ...
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Input Capacitor Selection The input capacitor has to sustain the ripple current produced during the on time of the upper MOSFET must have a low ESR to minimize the losses. The RMS value of this ripple is: Iin ...
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... The pole of the compensation network is calculated as, REF 100% Figure 11. Gain Plot of the Error Amplifier R 1 Thermal Considerations The power dissipation of the NCP1587 varies with the MOSFETs used average MOSFET gate current typically dominates the + control IC power dissipation. The IC power dissipation is − ...
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... Please note that the capacitors C and C each represent numerous physical IN OUT capacitors desirable to locate the NCP1587 within 1 inch of the MOSFETs, Q1 and Q2. The circuit traces for the MOSFETs’ gate and source connections from the NCP1587 must be sized to handle peak current. V BST Figure 12 ...
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... Figure 13. Closed-loop Voltage Loop-gain of the NCP1587 DESIGN EXAMPLE II: Type III Compensation (Oscon Cap. with small ESR; Do not place R Switching Frequency F Output Capacitance R Output Capacitance C Output Inductance L Input Voltage V Output Voltage V Choose the loop gain crossover frequency KHz The corner frequency of the output filter is calculated below; ...
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... 275 kHz 12 kW Figure 14. Closed-loop Voltage Loop-gain of the NCP1587 Choose The recommended compensation values are kW kW 665 12.1 kW C20 = 3 48.23 pF Blue curve: Gain-Frequency Red curve: Gain-Frequency (Phase margin = 80.285 degree, Gain margin = 19.362 dB) http://onsemi ...
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VCC GND 5 3 Figure 15. Demo Board PCB Layout http://onsemi.com 13 ...
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... J23 5PIN DNP NTD4815 NTD4815 NTD4806 NTD4806 DNP NTHS5404T1 R1 10 1.02 K DNP R5 5.11 0 R8, R639 DNP R9 0 100 K 0.56 49.9 RC 604 TP U1 NCP1587 http://onsemi.com 14 Quantity MFG 1 PANASONIC TAIYO YUDEN 1 AVX 2 PANASONIC PANASONIC TDK 1 ON SEMICONDUCTOR 1 PANASONIC 1 MOLEX ...
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... Figure 16. Gate Waveforms 20 A Load Sustaining Figure 18. Start-up Sequence Figure 17. Over Current Protection (12 Trip) Figure 19. Transient Response 0-10 A Load Step NCP1587 Efficiency Load Current (A) Figure 20. Efficiency vs. Load Current http://onsemi.com ...
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... D 0.33 0.51 0.013 0.020 G 1.27 BSC 0.050 BSC H 0.10 0.25 0.004 0.010 J 0.19 0.25 0.007 0.010 J K 0.40 1.27 0.016 0.050 0.25 0.50 0.010 0.020 S 5.80 6.20 0.228 0.244 1.270 0.050 mm inches ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1587 ...