NCP1546 ON Semiconductor, NCP1546 Datasheet
NCP1546
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NCP1546 Summary of contents
Page 1
... A, 170 kHz, Buck Regulator with Synchronization Capability The NCP1546 is a 1.5 A buck regulator IC operating at a fixed−frequency of 170 kHz. The device uses the V architecture to provide unmatched transient response, the best overall regulation and the simplest loop compensation for today’s high−speed logic ...
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... Vsw Vin SHDNB BOOST SYNC Vc GND Vfb NCP1546 SHDNB SYNC Rating = Reflow: (Note 1) (Human Body Model) (Machine Model) (Charge Device Model) 18−Lead DFN Junction−to−Ambient Max MIN 40 V −0 −0 − ...
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... Driving of this pin should be avoided because on−chip test circuitry becomes active whenever current exceeding 0 forced into the IC. 9, 11, 12, 14, 15 Connection NCP1546 FUNCTION pin provides a connection point to the output of the error amplifier and input to the PWM C PIN CONNECTIONS ...
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... Sync Pin Bias Current Sync Threshold Voltage Shutdown Shutdown Threshold Voltage Shutdown Pin Bias Current Thermal Shutdown Overtemperature Trip Point Thermal Shutdown Hysteresis 3. Guaranteed by design, not 100% tested in production. NCP1546 < 70°C, 4.5 V< V < unless otherwise specified Test Conditions − − − ...
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... Guaranteed by design, not 100% tested in production. SHDNB V IN Shutdown Comparator 2.9 V LDO + Voltage Regulator − 1.3 V 1.46 V SHDNB V − 1.27 V − Amplifier NCP1546 (0°C < T < 70°C, 4.5 V< V < unless otherwise specified Test Conditions SHDNB V − 2.5 V BOOST SW Note 4 − − SYNC 5 ...
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... Frequency Foldback Threshold. In short circuit or over−load conditions, this reduces the power dissipation of the IC and external components. An external clock signal can sync the NCP1546 to a higher frequency. The rising edge of the sync pulse turns on the power switch to start a new switching cycle, as shown in Figure 4 ...
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... The frequency foldback feature is disabled during the sync mode. Figure 4. A NCP1546 Buck Regulator is Synchronized to an External 350 kHz Pulse Signal Power Switch and Current Limit The collector of the built−in NPN power switch is ...
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... V during power up. There is no voltage over−shoot SW after the output voltage reaches the regulation. If the supply voltage rises slower than the V over−shoot. 1.0 1.5 IN Figure 8. The Power Up Transition of NCP1546 http://onsemi.com 8 2 control , the pin and thus output COMP ...
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... I = quiescent current. Q NCP1546 The pre−driver current is used to turn on/off the power switch and is approximately equal worst case. During steady state operation, the IC draws this current from the Boost pin when the power switch is on and then receives it from the V pin when the switch is off. The pre− ...
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... DUTY CYCLE Figure 11. Input Capacitor RMS Current can be Calculated by Multiplying Y Value with Maximum Load Current at any Duty Cycle NCP1546 Selecting the capacitor type is determined by each design’s constraint and emphasis. The aluminum electrolytic capacitors are widely available at lowest cost. Their ESR and ESL (equivalent series inductor) are relatively high ...
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... The ESL prevents the output capacitor from quickly charging up the parasitic capacitor of NCP1546 Figure 13. The Output Voltage Ripple Using One 100 mF POSCAP Capacitor Figure 15. The Output Voltage Ripple Using ...
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... Foldback Current Limit. See Table 1 for Schottky diodes from ON Semiconductor which are suggested for use with the NCP1546 regulator. Inductor Selection When choosing inductors, one might have to consider maximum load current, core and copper losses, component height, output ripple, EMI, saturation and cost ...
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... PAD AS WELL AS THE TERMINALS. MILLIMETERS DIM MIN MAX A 0.80 1.00 A1 0.00 0.05 A3 0.20 REF b 0.18 0.30 D 6.00 BSC D2 3.98 4.28 E 5.00 BSC E2 2.98 3.28 e 0.50 BSC K 0.20 −−− L 0.45 0.65 5.30 18X 0.75 0.50 PITCH 18X 0.30 3.24 DIMENSIONS: MILLIMETERS ON Semiconductor Website: www.onsemi.com Order Literature: http://www.onsemi.com/orderlit For additional information, please contact your local Sales Representative NCP1546/D ...