NX2154A MICROSEMI [Microsemi Corporation], NX2154A Datasheet
NX2154A
Related parts for NX2154A
NX2154A Summary of contents
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... The NX2154/2154A operates at fixed 300kHz. The NX2154/2154A employs fixed loss-less current limiting by sensing the Rdson of synchronous MOSFET followed by hiccup feature.NX2154A has higher current limit threshold than NX2154. Feedback under voltage also triggers hiccup. Other features of the device are: 5V gate drive, Adaptive ...
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ABSOLUTE MAXIMUM RATINGS Vcc to GND & BST to SW voltage ................... 6.5V BST to GND Voltage ...................................... 50V Storage Temperature Range ............................. -65 Operating Junction Temperature Range ............. -40 NOTE1: Stresses above those listed in "ABSOLUTE MAXIMUM RATINGS", may ...
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... Tdead(L to Ldrv going Low to Hdrv H) going High, 10%-10% R (Ldrv) I=200mA source R (Ldrv) I=200mA sink I (Ldrv) source I (Ldrv) sink TLdrv(Rise) TLdrv(Fall) Tdead going Low to Ldrv L) going High, 10% to 10% NX2154 NX2154A NX2154/2154A Min TYP MAX Units 3.4 mS 1.7 300 kHz 1 2000 umho ...
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... This pin is connected to the source of the high side MOSFET and provides 8 SW return path for the high side driver. Also SW senses the low side MOSFETS current, when the pin voltage is lower than 360mV for NX2154, 540mV for NX2154A, hiccup will be triggered. Rev.1.2 02/26/07 ...
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... BLOCK DIAGRAM VCC 1.25V Bias Generator 0.8V COMP 0.3V START 0.8V Digital ramp start Up FB COMP START GND Figure 2 - Simplified block diagram of the NX2154/NX2154A Rev.1.2 02/26/07 70%Vp FB UVLO POR START OC OSC 0.6V CLAMP 1.3V CLAMP Hiccup Logic NX2154/2154A Hiccup Logic OC BST HDRV SW Control Logic VCC PWM LDRV ...
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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 - Working frequency Inductor current ripple RIPPLE Design ...
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Usually when this type of capacitors are selected, the amount of capaci- tance per single unit is not sufficient to meet the tran- sient ...
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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 capaci- tors ...
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Case 1: F <F <F LC ESR O power stage F LC 40dB/decade F ESR loop gain 20dB/decade compensator Figure 4 - Bode plot of Type III compensator (F <F <F ) ...
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Case 2: F <F < ESR power stage F LC 40dB/decade loop gain F ESR 20dB/decade compensator Figure 5 - Bode plot of Type III compensator Design example for type ...
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B. Type II compensator design If the electrolytic capacitors are chosen as power stage output capacitors, usually the Type II compensa- tor can be used to compensate the system. Type II compensator can be realized by simple RC circuit without ...
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R value by the following equation OSC ESR m 1.5V 2 30kHz 15uH = 33V 30m 5V 0.8V =13.3k Choose R =13. Calculate ...
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Conduction loss is simply defined as HCON OUT DS(ON LCON OUT DS(ON TOTAL HCON LCON where the R will increases as MOSFET junc- DS(ON) tion ...
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GND plane with multiple vias. One is not enough. This is very important. The same applies to the output capacitors and input capacitors. 6. Hdrv and Ldrv pins should be as close to MOSFET gate as possible. ...
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TYPICAL APPLICATION FOR LED 1uF 10k 1N4148 1uF 7 Comp 68nF 56pF 1.6k NX2154 6 Fb POT 100k 1k Waveforms for LED application 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0 0.2 0.4 0.6 LED CURRENT(A) Figure 11 - ...
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SOIC8 PACKAGE OUTLINE DIMENSIONS Rev.1.2 02/26/07 NX2154/2154A 16 ...
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Rev.1.2 02/26/07 NX2154/2154A 17 ...