NCP5423 ON Semiconductor, NCP5423 Datasheet
NCP5423
Related parts for NCP5423
NCP5423 Summary of contents
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... NCP5422A, NCP5423 Dual Out−of−Phase Synchronous Buck Controller with Current Limit The NCP5422A dual N−channel synchronous buck regulator controller. It contains all the circuitry required for two independent t control method to achieve the 2 buck regulators and utilizes the V fastest possible transient response and best overall regulation, while using the least number of external components. The NCP5422A/3 features out− ...
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... Q3 MTD3302 L2 1.5 V/ 1.3 mH C11−C13 MTD3302 3 × 680 mF/4 2 5.0 k ± 1.0% R8 C17 10 k ± 1.0% 100 pF Figure 1. Application Diagram 1.5 V/10 A and 1.8 V/10 A Converter NCP5422A, NCP5423 12 V MBR0530T MBR0530T1 R10 Q5 220 2N3904 0.2 mF MA3180 BST GATE(H)2 GATE(H)1 ...
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... GATE(L)1 GATE(L)2 Low−Side FET Driver for , Channel GND Ground IS+1, IS+2 Positive Current Sense for Channel IS−1, IS−2 Negative Current Sense for Channel NCP5422A, NCP5423 Rating Reflow: (Note MAX MIN 16 V −0.3 V 4.0 V −0.3 V 5.0 V −0 − ...
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... Artificial Ramp Minimum Pulse Width Oscillator Switching Frequency Switching Frequency Switching Frequency R Voltage OSC Phase Difference 2. Guaranteed by design, not 100% tested in production. NCP5422A, NCP5423 (0°C < T < 70°C; 0°C < T < 125° OSC = C = 1.0 nF, unless otherwise specified.) GATE(H)1,2 GATE(L)1,2 Test Conditions ...
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... V Input Power supply pin GATE(L)2 Low Side Synchronous FET driver pin for channel 2. 16 GATE(H)2 High Side Switch FET driver pin for channel 2. NCP5422A, NCP5423 < 70°C; 0°C < T < 125° 30 OSC = C = 1.0 nF, unless otherwise specified.) GATE(H)1,2 ...
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... IS−1 − − IS+2 + IS−2 − − + FAULT Set Dominant − 0.25 V − E/A OFF 5 1.0 V − V NCP5422A, NCP5423 R OSC CURRENT SOURCE GEN CLK1 OSC CLK2 FAULT PWM Comparator RAMP1 0.425 V − + FAULT PWM Comparator 2 RAMP2 E/A OFF + 0.425 V − − ...
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... The comparator response time and the transition speed of the main switch determine the load transient response. Unlike traditional control methods, the reaction NCP5422A, NCP5423 APPLICATIONS INFORMATION time to the output load step is not related to the crossover frequency of the error signal loop. ...
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... Pulse−by−pulse adjustment of duty cycle is provided to quickly ramp the inductor current to the required level. Since the inductor current cannot be changed NCP5422A, NCP5423 instantaneously, regulation is maintained by the output capacitors during the time required to slew the inductor current. For better transient response, several high frequency and bulk output capacitors are usually used ...
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... The designer must also ensure that the regulator component temperatures are kept within the manufacturer’s specified ratings at full load and maximum ambient temperature. NCP5422A, NCP5423 Selecting Feedback Divider Resistors V Figure 7. Selecting Feedback Divider Resistors Selection of Feedback Divider Resistors Feedback divider resistors R1 and R2 are selected based on a design trade− ...
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... Powdered iron cores are very suitable due to its high saturation flux density and have low loss at high frequencies, a distributed gap and exhibit very low EMI. NCP5422A, NCP5423 The minimum value of inductance which prevents inductor saturation or exceeding the rated FET current can ...
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... load current slew rate; OUT DI = load transient; OUT Dt = load transient duration time; NCP5422A, NCP5423 ESL = Maximum allowable ESL including capacitors, circuit traces, and vias; ESR = Maximum allowable ESR including capacitors and circuit traces output voltage transient response time. TR The designer has to independently assign values for the change in output voltage due to ESR, ESL, and output capacitor discharging or charging ...
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... V of ground when in the low state and to within 2 their respective bias supplies when in the high state. In practice, the FET gates NCP5422A, NCP5423 will be driven rail−to−rail due to overshoot caused by the capacitive load they present to the controller IC. ...
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... The power dissipation of the IC varies with the MOSFETs used and the NCP5422A operating frequency. The CC average MOSFET gate charge current typically dominates the control IC power dissipation. NCP5422A, NCP5423 The IC power dissipation is determined by the formula: P CONTROL(IC CC1 V CC1 ) I BST V BST ) P GATE(H)1 where: P CONTROL(IC quiescent supply current ...
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... One of the key factors in achieving tight dynamic voltage regulation is low ESR. Low ESR at the regulator output results in low output NCP5422A, NCP5423 voltage ripple. The consequence is, however, that very little voltage ramp exists at the control IC feedback pin (V resulting in increased regulator sensitivity to noise and the potential for loop instability ...
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... Use the two internal layers as the power and GND planes, the top layer for power connections and component vias, and the bottom layers for the noise sensitive traces. NCP5422A, NCP5423 6. Keep the inductor switching node small by placing the output inductor, switching and synchronous FETs close together. ...
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... Literature Distribution Center for ON Semiconductor P.O. Box 61312, Phoenix, Arizona 85082−1312 USA Phone: 480−829−7710 or 800−344−3860 Toll Free USA/Canada Fax: 480−829−7709 or 800−344−3867 Toll Free USA/Canada Email: orderlit@onsemi.com NCP5422A, NCP5423 PACKAGE DIMENSIONS SO−16 D SUFFIX CASE 751B−05 ISSUE J − ...