NCP1445 ONSEMI [ON Semiconductor], NCP1445 Datasheet
NCP1445
Related parts for NCP1445
NCP1445 Summary of contents
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... NCP1442, NCP1443, NCP1444, NCP1445 4.0 A 280 kHz/560 kHz Boost Regulators The NCP1442/3/4/5 products are 280 kHz/560 kHz switching regulators with a high efficiency, 4.0 A integrated switch. These parts operate over a wide input voltage range, from 2 The flexibility of the design allows the chips to operate in most power supply configurations, including boost, flyback, forward, inverting, and SEPIC ...
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... NCP1442, NCP1443, NCP1444, NCP1445 3 220 pF 0.01 mF 5.1 k GND MAXIMUM RATINGS Thermal Resistance Junction−to−Air, TO220−7 Version In Air (Socketed) Thermal Resistance Junction−to−Air, TO220−7 Version Thermal Resistance Junction−to−Air, PowerFLEX on 2.1 sq. in. 1 oz. Junction Temperature Range Storage Temperature Range, T ...
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... NCP1442, NCP1443, NCP1444, NCP1445 ELECTRICAL CHARACTERISTICS (2.7 V < V unless otherwise stated.) (See Note 2) Characteristic Positive and Negative Error Amplifiers FB Reference Voltage (NCP1442/4 only) NFB Reference Voltage (NCP1443/5 only) FB Input Current (NCP1442/4 only) NFB Input Current (NCP1443/5 only) FB Reference Voltage Line Regulation (NCP1442/4 only) ...
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... NCP1442, NCP1443, NCP1444, NCP1445 ELECTRICAL CHARACTERISTICS NCP1442/3/4/5 specifications unless otherwise stated.) (See Note 2) Characteristic Power Switch Switch Saturation Voltage Switch Current Limit Minimum Pulse Width Switch Transconductance DIV CC SW Switch Leakage General Operating Current Shutdown Mode Current Minimum Operation Input Voltage ...
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... NCP1442, NCP1443, NCP1444, NCP1445 V CC Shutdown 2.0 V Regulator Delay Timer Sync SS 200 k Negative 2.0 V Error Amp 250 k NFB + NCP1443/5 − only −0.65 V Detector 0.4 V Detector FB − NCP1442/4 + only Positive Error Amp 1.276 V Thermal Shutdown S PWM Oscillator Q Latch R Frequency Shift 5:1 Slope Compensation PWM Comparator + − ...
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... NCP1442, NCP1443, NCP1444, NCP1445 2 AMBIENT TEMPERATURE ( C) A Figure 3. Supply Current versus Temperature 800 700 600 500 400 300 200 100 0 0 0.5 1.0 1.5 2.0 2 SWITCH CURRENT (A) SW Figure 5. Switch Saturation Voltage versus ...
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... NCP1442, NCP1443, NCP1444, NCP1445 125 100 −0.665 −0.67 −0.675 −0.68 −0.685 V , NEGATIVE FEEDBACK VOLTAGE (V) NFB Figure 9. Switching Frequency versus Negative Feedback Voltage −2.46 −2.47 −2. 2 −2.49 −2. AMBIENT TEMPERATURE ( C) A Figure 11 ...
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... NCP1442, NCP1443, NCP1444, NCP1445 1.14 1.12 1.10 1.08 1.06 1.04 1.02 1. AMBIENT TEMPERATURE ( C) A Figure 15. V Threshold Voltage versus C Temperature 180 160 140 120 100 AMBIENT TEMPERATURE ( C) A Figure 17. Shutdown Delay versus Temperature (NCP1442) 4 ...
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... NCP1442, NCP1443, NCP1444, NCP1445 570 560 550 540 530 520 510 500 490 480 470 AMBIENT TEMPERATURE ( C) A Figure 21. Error Amplifier Transconductance versus Temperature 100 0 −100 −200 −300 −400 −500 −0.25 −0.2 −0.15 −0.1 −0.05 0 0.05 V −V , FEEDBACK VOLTAGE (mV) ...
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... NCP1442, NCP1443, NCP1444, NCP1445 THEORY OF OPERATION Current Mode Control Oscillator S Q − Power Switch V PWM Comparator In Out Driver X5 SUMMER 15 mW Slope Compensation Figure 26. Current Mode Control Scheme The NCP144X family incorporates a current mode control scheme, in which the PWM ramp signal is derived from the power switch current. This ramp signal is compared to the output of the error amplifier to control the on− ...
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... NCP1442, NCP1443, NCP1444, NCP1445 Switch Driver and Power Switch The switch driver receives a control signal from the logic section to drive the output power switch. The switch is grounded through emitter resistors (15 mW total) to the GND pin. The peak switching current is clamped by an internal circuit ...
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... NCP1442, NCP1443, NCP1444, NCP1445 The low frequency pole determined by the error P1, amplifier output resistance and C1 as 2pC1R O The first zero generated by C1 and R1 is 2pC1R1 The phase lead provided by this zero ensures that the loop has at least a 45 phase margin at the crossover frequency. ...
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... NCP1442, NCP1443, NCP1444, NCP1445 Magnetic Component Selection When choosing a magnetic component, one must consider factors such as peak current, core and ferrite material, output voltage ripple, EMI, temperature range, physical size and cost. In boost circuits, the average inductor current is the product of output current and voltage gain (V assuming 100% energy transfer efficiency ...
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... NCP1442, NCP1443, NCP1444, NCP1445 current I . Summing up, the output voltage peak−peak IN ripple can be calculated by OUT OUT(RIPPLE OUT) (f) I OUT OUT )(f) The equation can be expressed more conveniently in terms and I for design purposes as CC OUT OUT follows: ...
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... NCP1442, NCP1443, NCP1444, NCP1445 The improved circuit does not require a regulated voltage to operate properly. Unfortunately, a price must be paid for this convenience in the overall efficiency of the circuit. The designer should note that the input and output grounds are no longer common. Also, the addition of the current sense ...
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... NCP1442, NCP1443, NCP1444, NCP1445 Figure 39. Soft−Start Resistor R1 and capacitors C1 and C2 form the compensation network. At turn on, the voltage at the V starts to come up, charging capacitor C3 through Schottky diode D2, clamping the voltage at the V switching begins when V reaches the V C typically 1 ...
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... NCP1442, NCP1443, NCP1444, NCP1445 Power dissipation in a semiconductor device results in the generation of heat in the junctions at the surface of the chip. This heat is transferred to the surface of the IC package, but a thermal gradient exists due to the resistive properties of the package molding compound. The magnitude of the thermal gradient is expressed in manufacturers’ ...
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... NCP1442, NCP1443, NCP1444, NCP1445 ORDERING INFORMATION Operating Temperature Range Device NCP1442FR4 NCP1442FR4G NCP1442T NCP1443FR4 NCP1443FR4G 0 C < T NCP1443T NCP1444FR4 NCP1444T NCP1445FR4 NCP1445T †For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging Specifications Brochure, BRD8011/D ...
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... NCP1442, NCP1443, NCP1444, NCP1445 DETAIL 0.076 (0.003) S −T− K SEATING PLANE THERMAL DIE PAD PACKAGE THERMAL DATA Parameter R qJC R qJA *Depending on thermal properties of substrate. R PACKAGE DIMENSIONS PowerFLEX 7−PIN F SUFFIX CASE 936J−01 ISSUE O ...
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... NCP1442, NCP1443, NCP1444, NCP1445 PowerFLEX is a trademark of Texas Instruments Incorporated. ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. “ ...