nx2142 Microsemi Corporation, nx2142 Datasheet
nx2142
Related parts for nx2142
nx2142 Summary of contents
Page 1
... The NX2142/2142A controller is optimized to convert single supply up to 24V bus volt- age to as low as 0.8V output voltage. NX2142/2142A can function as a single supply controller with its 5V bias regulator. Internal UVLO keeps the regulator off until the supply voltage exceeds 7V where internal digi- tal soft starts get initiated to ramp up output ...
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... V in Rev. 1.1 10/28/ 150 125 o C SYM Test Condition V REF EN=HIGH Q _UVLO V Rising CC CC _Hyst V Falling Vin=24V _UVLO V Rising in in NX2142/2142A = Typical A Min TYP MAX Units 0 4 ...
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... 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 L) High, 10% to 10% percent of nominal NX2142/2142A Min TYP MAX Units 0.5 V 600 KHz 1000 KHz 0.8 V 0.1 V/V 77 ...
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... This regulator request a 1uF ceramic X5R type output capacitor in order to be stable. This pin provides the input voltage to the 5V regulator controller as well as the VIN oscillator for the PWM feed forward to work. When VIN exceeds 6V, the converter starts to operate. Rev. 1.1 10/28/07 PIN DESCRIPTION NX2142/2142A 4 ...
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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 START POR 0.6V CLAMP 1.3V CLAMP Hiccup Logic NX2142/2142A Regout BST HDRV SW Control ...
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... BST 1 BST C1 0.1u U_HDRV HDRV 2 2 HDRV U_SW 10 SW U_LDRV LDRV 4 4 LDRV 25n R7 R10 R9 10k 953 C4 52p C3 3.3n COMP 9 COMP NX2142/2142A Ci1 25TQC33M C14 1u M5A STM6912 VOUT Lo SW OUT(5V DO3316P-682 Co1 1000uF, 6.3v,30mohm GNDOUT R15 M6B 10 STM6912 C9 470p R8 1.2k 4.99k 6 ...
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... M5, R10 18 1 R15 Rev. 1.1 10/28/07 NX2142/2142A Value Manufacture 25TQC33M SANYO 6MV1000W G SANYO 0.1u 1u 3.3n 52p 25n 470p 47u BAT54A Fairchild DO3316P-682 Coilcraft AO4800 AOS MMBT3904 Fairchild 10k 1.2k 4.99k 1% 953 1% 10 NX2142CUTR NEXSEM INC. 7 ...
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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 Figure 5 - Output voltage transient response (VIN=12V, IOUT=3A) Figure 7 - Startup 2500 3000 3500 NX2142/2142A 8 ...
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... For example, for 50mV output ripple, Electrolytic ...(1) 6ME1000WG with 30m Number of Capacitor is calculated as 30m 0.919A N 50mV N =0.55 The number of capacitor has to be round integer. Choose N =1. NX2142/2142A V 1 OUT OUT ...( 0.919A 20V 600kHz I ...
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... ESR, OUT but also capacitance. number of capacitor is ...(7) N crit OUT ...(8) I step The number of capacitors has to satisfy both ripple and transient requirement. Overall, we choose N=1. NX2142/2142A For low frequency ca- is true crit step OUT 2 ...( tran E ...
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... ESR is lower than crossover frequency. Otherwise type III compensator should be chosen. Voltage feedforward compensation is used in NX2142 to compensate the output voltage variation caused by input voltage changing. The feedforward funtion is realized by using VIN pin voltage to program the oscillator ramp voltage V ...
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... Choose C is shown as the s 6. Set zero F late =18k Choose R 7. Calculate 221 Choose R NX2142/2142A equal to 10k 0.5 9.2kHz 10k =3.9nF equation (14) with pole 10k 300kHz =52pF. 1 ...
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... Calculate C 1/10~ 1/5 of the switching frequency. Set shown s Choose C 6. Set zero =2k Choose R 7. Calculate R NX2142/2142A 1 ESR C OUT 1 30m 1000uF equal to 10k 0.75 1.93kHz 10k =10nF equation (14) with pole ...
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... Sanyo electrolytic CAP 6MV1500WGL are used as output capacitors. Coilcraft DO5010P-152HC 1.5uH is used as output inductor. The power stage information is that: V =12V OUT 1.Calculate the location of LC double pole F and ESR zero F NX2142/2142A 40dB/decade 20dB/decade Gain ...
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... Input voltage is 12V, output voltage is 2.5V, output inductor is 2.2uH, output capacitors are F p two 680uF with 41m 1.Calculate the location of LC double pole F and ESR zero NX2142/2142A introduce a zero to cancel the double 1 introduces a pole to suppress the switch ... (18) ...
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... I I RMS OUT V OUT D V INMIN V = 8V, V INMIN input RMS current is 3.4A. For higher efficiency, low ESR capacitors are recommended. One Sanyo OSCON CAP 25SVP56M NX2142/2142A and voltage di- OUT REF Fb Vref ...(21 part of the compensator, and the value ...
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... Over Current Limit Protection Over current Limit for step down converter is achieved by sensing current through the low side =30V, I MOSFET. For NX2142, the current limit is decided the R of the low side mosfet. When synchronous ...
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... These two grounds must be connected together on the PC board layout at a single point. The goal is to localize the high current path to a separate loop that does not interfere with the more sensitive ana- log control function. Rev. 1.1 10/28/07 need to be practi- NX2142/2142A 18 ...