NX2142A MICROSEMI [Microsemi Corporation], NX2142A Datasheet
NX2142A
Related parts for NX2142A
NX2142A Summary of contents
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... Vin +8 to 20V 47uF MMBT3904 0.1uF 20k 27pF 5.2nF Device Temperature NX2142CUTR NX2142ACUTR Rev. 1.1 10/28/07 AND 5V BIAS REGULATOR n Bus voltage operation from 7V to 24V n 5V bias regulator available n Excellent dynamic response with input voltage feed-forward and voltage mode control Voltage ...
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ABSOLUTE MAXIMUM RATINGS VCC to GND & BST to SW voltage ...................... -0.3V to 6.5V VIN to GND ........................................................ -0.3V to 30V BST to GND Voltage .......................................... -0.3V to 35V SW to GND ....................................................... -2V to 35V REGOUT to GND ...
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... Test Condition V _Hyst V Falling NX2142 S NX2142A V Vin=20V RAMP F =600kHz S Ib Tss NX2142 NX2142A (Hdrv) I=200mA source (Hdrv) I=200mA sink 10% to 90% 90% to 10% Ldrv going Low to Hdrv going H) High, 10% to 10% (Ldrv) I=200mA source (Ldrv) I=200mA sink 10% to 90% 90% to 10% SW going Low to Ldrv going ...
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PIN DESCRIPTIONS PIN SYMBOL This pin supplies the internal 5V bias circuit. A 1uF high frequency ceramic X5R capacitor must be placed as close as possible to this pin and ground pin to provide VCC high frequency bypass and to ...
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BLOCK DIAGRAM VIN 4.4/4.2V 1.25V Bias VCC Generator 0.8V 6V/ 5.5V COMP 0.3V VIN 0.8V START OSC Digital ramp start Up FB COMP START GND Figure 2 - Simplified block diagram of the NX2142 Rev. 1.1 10/28/07 Ref UVLO POR ...
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TYPICAL APPLICATION CIRCUIT BUS BUS(8-20V) C10 47u GNDBUS Q1 2N3904 U1 EN_REGOUT 6 EN/REG_OUT Figure 3- Demo board schematic(VIN=8-20V,VOUT=5V,IOUT=3A) Rev. 1.1 10/28/ 0.1u 1u BAT54A BST 1 BST C1 0.1u U_HDRV HDRV 2 2 HDRV U_SW 10 ...
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Bill of Materials Item Quantity Reference 1 1 Ci1 2 1 Co1 3 2 C1, C2,C14 C10 ...
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Demoboard waveforms Figure 4 - Output ripple (VIN=12V) Figure 6 - Over current protection 100.00% 95.00% 90.00% 85.00% 80.00% 75.00% 70.00% 65.00% 60.00% 55.00% 50.00% 0 500 1000 1500 2000 Iout(mA) Figure 8 - Output Efficiency(VIN=12V, VOUT=5V) Rev. 1.1 10/28/07 ...
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APPLICATION INFORMATION Symbol Used In Application Information Input voltage Output voltage OUT I - Output current OUT DV - Output voltage ripple RIPPLE F - Switching frequency Inductor current ripple RIPPLE Design ...
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If ceramic capacitors are chosen as output ca- pacitors, both terms in equation (3) need to be evalu- ated to determine the overall ripple. Usually when this type of capacitors are selected, the amount of capaci- tance per single unit ...
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It should be considered that the proposed equa- tion is based on ideal case, in reality, the droop or over- shoot is typically more than the calculation. The equa- tion gives a good start. For more margin, more ca- pacitors ...
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Case 1: F <F <F (for most ceramic or low LC O ESR ESR POSCAP, OSCON) power stage F LC 40dB/decade loop gain F ESR 20dB/decade compensator Figure 10 - Bode plot ...
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Calculate 20k 0.8V 2 REF 5V-0.8V OUT REF Choose R =5.7k 1 Case 2: F <F <F (for electrolytic capacitors) LC ESR O power stage F LC 40dB/decade F ...
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5.3kHz 25nF 1.2k Choose R =1. Calculate 1.2k 0.8V 2 REF 5V-0.8V OUT REF Choose R =381 ...
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OUT OUT 1 2 1.5uH 4500uF 1.94kHz 1 F ESR 2 ESR C OUT 1 2 6.33m 4500uF 5.6kHz 2.Set crossover frequency Set R equal Based on output ...
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F ESR 2 ESR C OUT 1 2 20.5m 1360uF 5.7kHz 2.Set R equal to10k . Using equation 18, the 2 final selection 4. Set crossover frequency at 1/10~ 1/5 of the swithing frequency, ...
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RMS rating are chosen as input bulk capacitors. Power MOSFETs Selection The NX2142 requires two N-Channel power MOSFETs. The selection of MOSFETs is based on maximum drain source voltage, gate source voltage, maximum current rating, ...
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EMI radiated by the power loop due to the high switching currents through them. 2. Low ESR capacitor which can handle input RMS ripple current and a high frequency decoupling ceramic cap which usually is 1uF cally ...