mic4742 Micrel Semiconductor, mic4742 Datasheet
mic4742
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mic4742 Summary of contents
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... MIC4742 allows efficiencies over 92%, reduces external components count and eliminates the need for an expensive current sense resistor. The MIC4742 operates from 2.9V to 5.5V 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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... Pin Configuration 16-Pin 3mm x 3mm MLF December 2008 Voltage Junction Temp. Range Adj. –40° to +125°C Adj. –40° to +125°C ® (YML) 2 Package Lead Finish ® 16-Pin 3x3 MLF Pb-Free 16-Pin EPAD TSSOP Pb-Free 16-Pin ETSSOP (YTSE) M9999-120908-B MIC4742 ...
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... SGND Signal (Analog) Ground. Provides return path for control circuitry and internal reference. BIAS Internal circuit bias supply. Must be bypassed with a 0.1µF ceramic capacitor to SGND. Biased through a 10Ω resistor to VIN. GND Connect to ground. 3 MIC4742 M9999-120908-B ...
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... J ® 3mm x 3mm MLF (θ ).....................................60°C/W JA EPAD TSSOP (θ )............................................35°C/W JA Min Typ 2.9 2.45 2.6 100 = 5.5V 1.4 = 3.6V 1.0 1.6 0.588 0.6 1 2.5 4.3 0.07 0.2 100 155 1.5 2 180 0.5 0.9 55 0.1 153 18 MIC4742 IN < +125°C. J Max Units 5 µA 0.612 mΩ 2.3 MHz Deg 1 µA °C °C M9999-120908-B ...
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... OUTPUT CURRENT (A) 3.3Vin 2.5Vout Efficiency 4.5Vin 80 5.0Vin 78 5.5Vin 76 0 0.4 0.8 1.6 2 OUTPUT CURRENT (A) Load Regulation 1.005 1.000 0.995 0.990 4.5Vin 5.0Vin 5.5Vin 0.985 1 0.4 0.8 OUTPUT CURRENT (A) MIC4742 3.0Vin 3.3Vin 3.6Vin 1.2 1.6 2 4.5Vin 5.0Vin 5.5Vin 1.2 1.6 2 3.0Vin 3.3Vin 3.6Vin 1.2 1.6 2 Vin=3.3V 1.2 1.6 2 M9999-120908-B ...
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... TEMPERATURE (°C) Quiescent Current vs. Supply Voltage 1600 1200 800 400 0 0.00 1.00 2.00 3.00 4.00 5.00 SUPPLY VOLTAGE (V) Enable Threshold vs. Supply Voltage 1.20 1.00 0.80 0.60 0.40 0.20 0.00 2.9 3.3 3.7 4.1 4.5 4.9 5.3 SUPPLY VOLTAGE (V) 6 MIC4742 Frequency vs. Temperature 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1.6 1.5 -40 - 100 120 TEMPERATURE (°C) Rdson vs. Supply Voltage 180 170 160 150 140 130 120 110 100 2 ...
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... Micrel, Inc. Functional Characteristics December 2008 7 MIC4742 M9999-120908-B ...
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... Micrel, Inc. Functional Diagram December 2008 MIC4742 Block Diagram 8 MIC4742 M9999-120908-B ...
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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 MIC4742. 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 MIC4742 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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... In Figure drawn voltage, but to see actual operation (with ringing) refer to the functional characteristics. Discontinuous mode of operation has the advantage over full PWM in that at light loads, the MIC4742 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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... Micrel, Inc. Where D is the duty cycle. Since the MIC4742 uses an internal P-channel MOSFET, Rdson losses are inversely proportional to supply voltage. Higher supply voltage yields a higher gate to source voltage, reducing the Rdson, reducing the MOSFET conduction losses. A graph showing typical Rdson vs input supply voltage can be found in the typical characteristics section of this datasheet ...
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... Increasing C decrease and vice versa. Inductor Selection The MIC4742 is designed for use with a 1µH inductor. Proper selection should ensure the inductor can handle the maximum average and peak currents required by the load. Maximum current ratings of the inductor are generally given in two methods ...
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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 MIC4742, it utilizes type III compensation. This is a dominant low frequency pole, followed by 2 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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... December 2008 100000 1000000 By looking at the graph, phase margin can be affected to a greater degree with higher output voltages. 15 Max. Amount of Phase Boost Obtainable Using Cff vs. Output Voltage OUTPUT VOLTAGE (V) M9999-120908-B MIC4742 ...
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... If there does not happen to be any non-shielded bus wire immediately available, the leads from axial resistors will work. shortest possible ground lengths on the oscilloscope probe, true ripple measurements can be obtained. December 2008 By maintaining the 16 MIC4742 M9999-120908-B ...
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... B230A L1,L2 IHLP2525AH-01 1R0 RLF7030-1R0 N HCP0703-1R0 R11,R12 CRCW060310K0FKXX R12,R22 CRCW06033K16FKXX CRCW06034K99FKXX CRCW06036K65FKXX CRCW060310K0FKXX CRCW060315K0FKXX * only for ultra-low noise applications. December 2008 MIC4742YML Schematic for 2A Output Manufacturer Description (1) Murata (2) TDK 10µF Ceramic Capacitor X5R 0603 6.3V (3) AVX (4) Vishay 680pF Ceramic Capacitor NPO 0603 6.3V (4) Vishay ...
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... Cooper: www.cooperbussmann.com 6. Diode: www.diodes.com 7. Micrel, Inc : www.micrel.com * only for ultra-low noise applications. December 2008 Manufacturer Description (4) Vishay 2.7Ω1% 0603 resistor (4) Vishay 49.9kΩ1% 0603 resistor (4) Vishay 10Ω1% 0603 resistor (7) Micrel, Inc. Dual 2A 2MHz Integrated Switch Buck Regulator 18 MIC4742 Qty M9999-120908-B ...
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... Micrel, Inc. MIC4742YML Layout Recommendation: 2A Evaluation Board December 2008 Recommended TOP Layout Recommended Bottom Layout 19 MIC4742 M9999-120908-B ...
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... Micrel, Inc. Package Information December 2008 ® 16-Pin 3mm x 3mm MLF (ML) 20 MIC4742 M9999-120908-B ...
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... Micrel, Inc. December 2008 16-Pin ETSSOP 21 MIC4742 M9999-120908-B ...
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... A 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 December 2008 indemnify Micrel for any damages resulting from such use or sale. © 2008 Micrel, Incorporated. 22 MIC4742 M9999-120908-B ...