mic4782 Micrel Semiconductor, mic4782 Datasheet
mic4782
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mic4782 Summary of contents
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... MIC4782 allows efficiencies over 92%, reduces external components count and eliminates the need for an expensive current sense resistor. The MIC4782 operates from 3.0V to 6.0V input and the output can be adjusted down to 0.6V. The device can operate with a maximum duty cycle of 100% for use in low- dropout conditions. ...
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... GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free. Pin Configuration August 2009 Voltage Junction Temp. Range Adj. –20° to +125°C 16-Pin 3mm x 3mm MLF 2 Package Lead Finish ® 16-Pin 3mm x 3mm MLF ® (YML) MIC4782 Pb-Free M9999-081709-D ...
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... Feedback for output 1 (Input). Input to the error amplifier, connect to the external resistor divider network to set the output voltage. Signal (Analog) Ground. Provides return path for control circuitry and internal reference. Internal circuit bias supply. Must be bypassed with a 0.1µF ceramic capacitor-to-SGND. Biased through a 10Ω resistor to VIN. Connect to ground. 3 MIC4782 M9999-081709-D ...
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... ........................ –20°C to +125°C J ® 3mm x 3mm MLF (θ ).....................................60°C/W JA Min Typ 3.0 2.45 2.6 100 = 6V 1.4 = 3.6V 1.0 1.6 589 607 1 2.5 4.3 0.07 0.2 100 155 1.8 180 0.5 0.9 55 0.1 153 18 MIC4782 IN < +125°C. J Max Units 6 µA 625 mΩ MHz Deg 1 µA °C °C M9999-081709-D ...
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... OUTPUT CURRENT (A) 3.3V , 2.5V IN OUT 4.5Vin 80 5.0Vin 78 5.5Vin 76 0 0.4 0.8 1.6 2 OUTPUT CURRENT (A) Load Regulation 0.615 0.610 0.605 0.600 4.5Vin 5.0Vin 5.5Vin 0.595 0 0.4 0.8 1.6 2 OUTPUT CURRENT (A) MIC4782 Efficiency 3.0Vin 3.3Vin 3.6Vin 1.2 1.6 2 Efficiency 4.5Vin 5.0Vin 5.5Vin 1.2 1.6 2 Efficiency 3.0Vin 3.3Vin 3.6Vin 1.2 1.6 2 Vin=3.3V 1.2 1.6 2 M9999-081709-D ...
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... Temperature 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 - 100 120 TEMPERATURE (°C) vs. Supply Voltage 190 180 170 160 150 140 130 120 110 3.6 SUPPLY VOLTAGE (V) Enable Threshold vs. Temperature 1.2 1.0 0.8 0.6 0.4 0.2 0.0 5 TEMPERATURE (°C) MIC4782 Frequency 100 120 Rdson 4.2 4.8 5 100 120 M9999-081709-D ...
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... Micrel, Inc. Functional Characteristics August 2009 7 MIC4782 M9999-081709-D ...
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... Micrel, Inc. Functional Diagram August 2009 MIC4782 Block Diagram 8 MIC4782 M9999-081709-D ...
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... Please refer to layout recommendations for more details. BIAS The bias (BIAS) provides power to the internal reference and control sections of the MIC4782. A 10Ω resistor from VIN to BIAS and a 0.1µF from BIAS to SGND are required for clean operation. EN1/EN2 The enable pins (EN1 and EN2) provides a logic level control of the outputs 1 and 2 ...
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... Micrel, Inc. Application Information The MIC4782 is a dual 2A PWM non-synchronous buck regulator. By switching an input voltage supply, and filtering the switched voltage through an inductor and capacitor, a regulated DC voltage is obtained. Figure 1 shows a simplified example of a non-synchronous buck converter. Figure 1. Example of Non-synchronous Buck Converter For a non-synchronous buck converter, there are two modes of operation ...
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... August 2009 Discontinuous mode of operation has the advantage over full PWM in that at light loads, the MIC4782 will skip pulses as necessary, reducing gate drive losses, drastically improving light load efficiency. Efficiency Considerations Calculating the efficiency is as simple as measuring power out and dividing it by the power in ...
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... Also, with higher load currents, these losses are higher. For discontinuous operation, the transition losses only occur during the “off” transition since the “on” transitions there is no current flow through the inductor. 12 MIC4782 losses due to the ) are ...
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... PGND pins for high frequency filtering. Smaller case size capacitors are recommended due to their lower ESR and ESL. Please refer to layout recommendation for proper layout of the input capacitor. Output Capacitor The MIC4782 is designed to be stable with a 4.7µF output capacitor. X5R or recommended for the output capacitor ...
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... Micrel, Inc. higher -20 -40 -60 0603 X5R 6.3V Ceramic Capacitor -80 0805 X5R 6.3V Ceramic Capacitor -100 VOLTAGE APPLIED (V) Figure 7. Voltage Derating of Ceramic Capacitors August 2009 MIC4782 M9999-081709-D ...
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... The network analyzer will then sweep the source while monitoring A and R for an A/R measurement. The following Bode analysis show the small signal loop stability of the MIC4782, it utilizes type III compensation. This is a dominant low frequency pole, followed by two zeros and finally the double pole of the inductor capacitor filter, creating a final 20dB/decade roll off. Bode analysis gives us a few important data points ...
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... August 2009 100000 1000000 By looking at the graph, phase margin can be affected to a greater degree with higher output voltages. 16 Max. Amount of Phase Boost Obtainable Using Cff vs. Output Voltage OUTPUT VOLTAGE (V) M9999-081709-D MIC4782 ...
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... If there does not happen to be any non-shielded bus wire immediately available, then the leads from axial resistors will work. By maintaining the shortest possible ground lengths on the oscilloscope probe, true ripple measurements can be obtained. August 2009 17 MIC4782 M9999-081709-D ...
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... PCB Layout is critical to achieve reliable, stable and efficient performance. A ground plane is required to control EMI and minimize the inductance in power, signal and return paths. The following guidelines should be followed to insure proper operation of the MIC4782 converter. IC • Place the IC and MOSFETs close to the point of load (POL). ...
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... IHLP2525AH-01 1R0 RLF7030-1R0 N HCP0703-1R0 R11,R12 CRCW060310K0FKXX R12,R22 CRCW06033K16FKXX CRCW06034K99FKXX CRCW06036K65FKXX CRCW060310K0FKXX CRCW060315K0FKXX August 2009 MIC4782YML Schematic for 2A Output Manufacturer Description (1) AVX 10µF, Ceramic Capacitor, X5R, 0805, 10V (2) Vishay 680pF, Ceramic Capacitor, NP0, 0603, 25V (2) Vishay 82pF, Ceramic Capacitor, NP0, 0603, 25V ...
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... TDK: www.tdk.com 5. Cooper: www.cooperbussmann.com 6. Micrel, Inc: www.micrel.com 7. Only for ultra-low noise applications. August 2009 Manufacturer Description (2) Vishay 2.7Ω, 1%, 0603, resistor (2) Vishay 49.9kΩ, 1%, 0603, resistor (2) Vishay 10Ω, 1%, 0603, resistor (6) Micrel, Inc. Dual, 2A, 1.8MHz, Integrated Switch Buck Regulator 20 MIC4782 Qty M9999-081709-D ...
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... Micrel, Inc. MIC4782YML Layout Recommendation: 2A Evaluation Board August 2009 TOP Layer Mid-Layer 1 21 MIC4782 M9999-081709-D ...
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... Micrel, Inc. August 2009 Mid-Layer 2 Bottom Layer 22 MIC4782 M9999-081709-D ...
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... Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully August 2009 16-Pin 3mm x 3mm MLF indemnify Micrel for any damages resulting from such use or sale. © 2009 Micrel, Incorporated. 23 ® (ML) MIC4782 nt M9999-081709-D ...