nx2141 Microsemi Corporation, nx2141 Datasheet
nx2141
Related parts for nx2141
nx2141 Summary of contents
Page 1
... Internal UVLO keeps the regulator off until the supply voltage exceeds 7V where internal digital soft starts get initiated to ramp up output. The NX2141 employs fixed current limiting and FB UVLO followed by hiccup feature. Other features includes: 5V gate drive capability , Adaptive dead band control, avail- able in 16 lead MLPQ and 10 lead MSOP package ...
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... SYM Test Condition V REF EN=HIGH Q I EN=LOW SD _UVLO V Rising CC CC _Hyst V Falling Vin=24V EN=LOW NX2141 10-LEAD PLASTIC MSOP BST HDRV COMP GND 7 4 VCC LDRV VIN - Typical ...
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... I=200mA (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 L) High, 10% to 10% NX2141 Min TYP MAX Units 6 V 0.5 V 200 KHz % - 0.8 V 0.1 V/V 88 ...
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... Supply voltage for the low side fet drivers. A high frequency 1uF ceramic cap must be connected from this pin to the PGND pin as close as possible. PVCC Rev. 1.6 05/15/07 SYM Test Condition FB ramping up percent of nominal PIN DESCRIPTION NX2141 Min TYP MAX Units ...
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... BLOCK DIAGRAM 1.25V Bias VCC Generator 0.8V VIN 6V/ 5.5V COMP 0.3V 0.8V START OSC Digital ramp start Up FB COMP START DISABLE EN AGND Figure 2 - Simplified block diagram of the NX2141(MLPQ) Rev. 1.6 05/15/07 POR UVLO START OC VIN S Q DISABLE R POR 0.6V CLAMP 1.3V CLAMP Hiccup Logic NX2141 PGOOD FB 0.85Vref /0.90Vref BST ...
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... Figure 3 - Simplified Demo board schematic(MLPQ) Rev. 1.6 05/15/07 1uH 10 1uF 0.1uF MBR0530T1 0.1uF BST VIN PVCC VCC 1 Hdrv M1 PGOOD COMP 3 Ldrv M2 FB Pgnd Gnd 2 17 NX2141 25TQC33M 25V,33uF 1uH Vout +1.05V 10A Co 2*2R5TPE220MC (220uF,12mohm) 1.5k 10k 2.2nF 32k 6 ...
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... Figure 4 - Demo board schematic based on ORCAD Rev. 1.6 05/15/07 NX2141 7 ...
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... R10 19 1 R12 20 1 R13 21 1 R15 Rev. 1.6 05/15/07 Part Manufacturer 0.1u 1u 25TQC33M SANYO 47u 15nF 1000pF 2.2n 470p 2R5TPE220MC SANYO MBR0530T1 MLC1550-102ML Coilcraft FDS6294 Fairchildsemi FDS6676AS Fairchildsemi 0 10 100k 2.3k 32k 10k 1.5k 1k NX2141CMTR NEXSEM INC. L78L05AB/sot89 NX2141 8 ...
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... AC(50mV/div), CH2 output current(5A/div)) Figure 9 - Over Current Protection(CH2 output current(10A/ div), CH4 VOUT(500mV/div)) Rev. 1.6 05/15/07 Figure 6 - Transient response(CH1 Vout AC(50mV/div), CH2 output current(5A/div)) Figure 8 - Enlarged transient response(CH1 Vout AC(50mV/div), CH2 output current(5A/div)) Figure 10 - Power Good(CH4 Vout(500mV/div), CH3 PGOOD(5V/div)) NX2141 9 ...
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... Iout(VIn=12V) 89.00% 88.00% 87.00% 86.00% 85.00% 84.00% 83.00% 82.00% 81.00% 80.00% 79.00 Iout(A) Figure 15 - Efficiency(VIN=12V, VOUT=1V) Rev. 1.6 05/15/07 Figure 12 - Enlarged Figure 11 (CH1 Vout AC(50mV/ div), CH3 VIN(5V/div), CH4 SW(5V/div)) Figure 14 - Soft start(CH1 EN(2V/div),CH2 output current(10A/div), CH3 VOUT(500mV/div)) 86.00% 84.00% 82.00% 80.00% 78.00% 76.00% 74.00 Figure 16 - Efficiency(VIN=19V, VOUT=1V) NX2141 efficinecy vs Iout(VIn=19V Iout(A) 10 ...
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... For example, for 30mV output ripple, POSCAP ...(1) 2R5TPE220MC with 12m are chosen Number of Capacitor is calculated as 12m N 30mV N =2 =1uH, then OUT The number of capacitor has to be round integer. Choose N =2. NX2141 V 1 OUT OUT OUT IN S ...(2) 1 4.97A ...
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... ESR, but also capaci- OUT tance. number of capacitor is L ...(7) V crit 1.05V OUT ...(8) ESR I step N 12m 53mV 1.35 NX2141 true. In that case, the crit step 2 OUT tran E tran crit I ...(10) step ESR C ...
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... ESR is lower than cross- over frequency. Otherwise type III compensator should be chosen. Voltage feedforward compensation is used in NX2141 to compensate the output voltage variation caused by input voltage changing. The feedforward funtion is realized by using VIN pin voltage to program the oscil- lator ramp voltage V =0 ...
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... =1.7nF Choose C 6. Calculate 1.2k Choose R 7. Calculate R at the LC double pole 8.35k Choose R NX2141 equal to 2.5k with zero F at 75% of the 0.75 7.59kHz 2.5k =15nF equation (14) with pole ...
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... OSC =10 is shown as =1.08k s Choose R 6. Calculate 14nF Choose C 7. Calculate R at the LC double pole. NX2141 1 ESR C OUT 1 9m 2000uF equal to 2.5k 4 with zero F at 75% of the 0.75 2.4kHz 2.5k =33nF equation (14) with pole F ...
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... Input voltage is 12V, output voltage is 2.5V, output inductor is 2.2uH, output capacitors are two 680uF with 41m electrolytic capacitors. 1.Calculate the location of LC double pole F and ESR zero 2.9kHz F ESR 5.7kHz 3 NX2141 ...(15 ... (16 ...
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... 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 25V 56uF 28m with 3.8A RMS rating are chosen as input bulk capacitors. NX2141 Fb Vref ...(18 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 MOSFET. For NX2141, the current limit is decided by the R of the low side mosfet. When synchronous DSON =30V, I ...
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... In multilayer PCB, separate power ground and analog ground. 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. 1.6 05/15/07 NX2141 19 ...
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... MLPQ 16 PIN PACKAGE OUTLINE DIMENSIONS NOTE: ALL DIMENSIONS ARE DISPLAYED IN MILLIMETERS. Rev. 1.6 05/15/07 NX2141 20 ...
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... MLPQ 16 PIN TAPE AND REEL INFORMATION NOTE INCH LOCK REEL, R13 = 13 INCH LOCK REEL. 2. ALL DIMENSIONS ARE DISPLAYED IN MILLIMETERS. Rev. 1.6 05/15/07 NX2141 21 ...