nx2113 Microsemi Corporation, nx2113 Datasheet
nx2113
Related parts for nx2113
nx2113 Summary of contents
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... SYNCHRONOUS PWM CONTROLLER WITH DESCRIPTION The NX2113 controller synchronous Buck con- troller IC designed for step down converter applications. Synchronous control operation replaces the traditional catch diode with an Nch MOSFET resulting in improved converter efficiency. The NX2113 controller is optimized to convert bus voltages from 2V to 25V to outputs as low as 0 ...
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... LOAD S (Static) Outputs not switching I C =3300pF F =300kHz BST LOAD S _UVLO V Rising CC CC _Hyst V Falling CC CC Tss Fsw=300Khz, 2113 Fsw=600Khz, 2113A NX2113/2113A 10-LEAD PLASTIC MLPD Comp PAD 3 8 (Gnd Vcc = Typical values refer to T ...
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... V -V =4.5V BST SW Tdead(L to Ldrv going Low to Hdrv H) going High, 10%-10% R (Ldrv) I=200mA source R (Ldrv) I=200mA sink TLdrv(Rise) 10% to 90% TLdrv(Fall) 90% to 10% Tdead going Low to Ldrv L) going High, 10% to 10% NX2113/2113A Min TYP MAX Units 300 kHz 600 kHz 2 2100 umho 10 nA 0.4 V 1. ...
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... This pin is the output of the error amplifier and together with FB pin is used to 9 COMP compensate the voltage control feedback loop. This pin is connected to the source of the high side MOSFET and provides return 10 SW path for the high side driver. Rev. 2.0 11/18/05 NX2113/2113A PIN DESCRIPTION 4 ...
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... BLOCK DIAGRAM 1.25V Bias VCC Generator 0.8V EN 1.25/1.15 START OSC Digital start Up FB COMP START GND Rev. 2.0 11/18/05 POR UVLO START FB 0 NX2113/2113A BST DRVH SW PVCC DRVL 5 ...
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... open 47p open 11k 10k Figure 2 - Demoboard design on NX2113A Rev. 2.0 11/18/05 L2 BUS1 D O 1608C -102 3706 ...
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... R15 Rev. 2.0 11/18/05 Reference Part OPEN .1uF 16SP270M 1uF 47pF 47uF 2.7nF OPEN 220uF 2R5TPE220MC 2.2nF 1uF D1N5819 CON2 SCOPE TP DO5010P-781HC DO1608C-102 IRFR3706 2N3904 0 10 11k 10k 1.2k 12.4k 68k 2k NX2113 NX2113/2113A Manufacture SANYO SANYO Tektronics Coilcraft Coilcraft International Rectifier NEXSEM INC. 7 ...
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... DEMO BOARD WAVEFORM Figure 3: Output efficiency Figure 5: Output voltage transient response for load curent 0A-9A Figure 7: ENABLE function.(Ch1-enable, Ch2-Ldrv, Ch3-output voltage) Rev. 2.0 11/18/05 NX2113/2113A Figure 4: Voltage ripple @1.6 V output voltage. (Ch2-ripple, Ch3-Hdrv) Figure 6: Start up time(Ch1-input volatge, Ch2-output voltage) Figure 8: Startup operation waveform 8 ...
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... Output voltage OUT I - Output current OUT DV - Output voltage ripple RIPPLE F - Working frequency Inductor current ripple RIPPLE Design Example The following is typical application for NX2113A, the schematic is figure 12V IN V =1.6V OUT I =10A OUT DV <=20mV RIPPLE DV <=80mV @ 10A step ...
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... ESR 12m E OUT ...(8) I 80mV step 2 1.5 H 220 F 80mV 1.7 The number of capacitors has to satisfy both ripple and transient requirement. Overall, we can choose N=3. NX2113/2113A true. In that case, the crit step 2 OUT tran E tran crit I step ...
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... OUT in To achieve the same effect as voltage amplifier, the compensator of transconductance amplifier must satisfy this condition: R4>>2/gm. R1||R2||R3>>1/gm is desirable. Vout Zin Figure 9 - Type III compensator using transconductance amplifier NX2113/2113A 1 ...(11 ...(12 ...(13 ...
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... Calculate C double pole by equation (11 2.75nF Choose C 6. Calculate C half the swithing frequency 48pF Choose C 7. Calculate 1.2k Choose R = 10k 1 . ESR NX2113/2113A 10k 7kHz 60kHz out 45kHz 0.78uH 660uF 2 ...
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... LC double pole F and ESR zero ESR 2.Set R 2 10k R 1 2.5V-0.8V 3. Set crossover frequency at 1/10~ 1/5 of the swithing frequency, here F 4.Calculate R V OSC 12V =10.3k Choose R NX2113/2113A ... (15 ... (16 ... (17 has to satisfy O <=1/10~1/ ...
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... One Sanyo OSCON SP series 16SP270M 16V 270uF with 4.4A is chosen as input bulk capacitor. Power MOSFETs Selection The NX2113 requires two N-Channel power MOSFETs. The selection of MOSFETs is based on maximum drain source voltage, gate source voltage, maximum current rating, MOSFET on resistance and power dissipation. The main consideration is the power loss contribution of MOSFETs to the overall converter efficiency ...
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... Figure 14 - Enable and Shut down NX2113 by pulling down EN pin. =0.14W. This GATE The start up of NX2113/2113A can be programmed through resistor divider at Enable pin. For example, if the input bus voltage is 12V and we want NX2113 starts when Vbus is above 8V. We can select K R2=1.24k ...(21) (8V 1.25V) R ...
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... The inductor, output capacitor and the MOSFET should be close to each other as possible. This helps to reduce the EMI radiated by the power traces due to the high switching currents through them. Place input ca- pacitor directly to the drain of the high-side MOSFET, to NX2113/2113A CH2-Output voltage 1V/DIV CH4-load current 10A/DIV ...
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... The goal is to localize the high current path to a separate loop that does not interfere with the more sen- sitive analog control function. These two grounds must be connected together on the PC board layout at a single point. Rev. 2.0 11/18/05 NX2113/2113A 17 ...
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... C4 47uF Vin R5 10 +5V C5 1uF 10nF 100pF R4 10k R2 4.7k 1% Figure 18 -Application of NX2113 for 5V bias and 12V input bus Single power supply (+11V to +24V BUS) Vin +11~25V 47uF 2N3904 R6 12.7k TL431 R7 10k C2 10nF C1 R4 100pF 10k R2 4.7k 1% Figure 19 -Application of NX2113 for high input bus application Rev ...
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... Vin +5V C4 10uF X7R 1uF Comp C1 R4 4.7pF 120k 330pF R2 20k 1% Figure 20 - Application of NX2113 A for 5V input and 1.6V output with ceramic output capacitors Rev. 2.0 11/18/05 L2 1uH D1 C6 1uF Vcc BST PVcc 0.1uF M1 2 Hdrv Ldrv Gnd ...