mic4724 Micrel Semiconductor, mic4724 Datasheet
mic4724
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mic4724 Summary of contents
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... MIC4724 allows efficiencies over 92%, reduces external components count and eliminates the need for an expensive current sense resistor. The MIC4724 operates from 3.0V to 6.0V input and the output can be adjusted down to 1V. The devices can operate with a maximum duty cycle of 100% for use in low- dropout conditions ...
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... Connect to ground. EP June 2008 Voltage Temperature Range Adj. –40° to +125° VIN 2 SGND 3 BIAS 10-Pin ePAD MSOP (MME) 2 Package Lead Finish 10-Pin ePAD MSOP Pb-Free VIN 8 PGND 7 PGOOD 6 EN MIC4724 M9999-062408-A ...
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... J (θ ) ...................................................................63°C/W JA < +125°C. J Min Typ Max 3.0 6.0 2.55 2.45 2.65 100 570 900 2 0.98 1. 100mA 0.07 0.2 100 110 2 0.85 0.5 1.3 50 0.1 2.3 ±7 ±10 150 300 160 25 MIC4724 IN Units µA µ mΩ mΩ MHz V mV µA % Ω ° C ° C M9999-062408-A ...
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... OUTPUT CURRENT (A) 3.3V Efficiency OUT 0.5 1 1.5 2 2.5 3 OUTPUT CURRENT (A) 4 MIC4724 1.2V Efficiency OUT 3. 3. 0.5 1 1.5 2 2.5 3 OUTPUT CURRENT (A) 1.5V Efficiency OUT ...
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... Supply Voltage 1.2 1.0 0.8 0.6 0.4 0.2 0 2.7 3.2 3.7 4.2 4.7 SUPPLY VOLTAGE (V) Thermal De-Rating Curves 3 3.3V OUT 1.2V OUT 1 100 120 AMBIENT TEMPERATURE (°C) 5 MIC4724 Frequency vs. Temperature 2.5 2.4 2.3 2.2 2.1 2.0 1.9 1.8 1.7 1 3. TEMPERATURE (°C) R DSON vs. Supply Voltage 120 115 110 105 100 2.7 3.2 3.7 4.2 4.7 5.2 SUPPLY VOLTAGE (V) Enable Threshold vs ...
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... Micrel, Inc. Functional Characteristics June 2008 6 MIC4724 M9999-062408-A ...
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... Micrel, Inc. Functional Diagram VIN VIN BIAS Enable and EN Control Logic June 2008 Bias, UVLO, Thermal Shutdown SGND IC M 4724 Block Diagram 7 P-Channel Current Limit HSD PWM Control Soft EA Start 1.0V 1.0V PGND MIC4724 PGOOD M9999-062408-A ...
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... Please refer to layout recommendations. BIAS The bias (BIAS) provides power to the internal reference and control sections of the MIC4724. A 10Ω resistor from VIN to BIAS and a 0.1µF from BIAS to SGND is required for clean operation. EN The enable pin provides a logic level control of the output. In the off state, supply current of the device is greatly reduced (typically < ...
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... Micrel, Inc. Application Information The MIC4724 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 MIC4724 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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... For discontinuous operation, the transition losses only occur during the “off” transition since the “on” transitions there is no current flow through the inductor. 11 Figure 6. Switching Transition Losses ) and the current through the switch (I S-D M9999-062408-A MIC4724 ) are S-D ...
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... Increasing COUT forces L to decrease and vice versa. Inductor Selection The MIC4724 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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... You should see a single sweeping eliminated. Figure 8 sinusoidal waveform without distortion on the output. If there is distortion of the sinusoid, reduce the amplitude of the source signal. You could be overdriving the feedback causing a large signal response. 13 MIC4724 +8V R1 MIC922BC5 Network Analyzer ...
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... Micrel, Inc. The following Bode analysis show the small signal loop stability of the MIC4724, 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. ...
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... As one can see, the typical phase margin, using the same resistor values as before without a feedforward capacitor results in 33.6 degrees of phase margin. Our prior measurement with a feedforward capacitor yielded a phase margin of 47 degrees. The feedforward capacitor has given us a phase boost of 13.4 degrees (47 degrees- 33.6 Degrees = 13.4 Degrees). 15 MIC4724 Bode Plot V =3.3V, V =1.8V, I =3A IN OUT ...
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... I × 707 R LOAD Output Impedance vs. Frequency 1 V =1.8V OUT L=1µH C =4.7µF + 0.1µ OUT 0.1 3.3VIN 0. 0.001 10 100 1k 10k 100k 1M FREQUENCY (Hz) A/sec = f π 2 ∆ = ∆ × OUT OUT OUT ↓ DCR X DSON L ↓ TOTAL ↑ GAIN M9999-062408-A MIC4724 X COUT ...
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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. June 2008 By maintaining the 17 MIC4724 M9999-062408-A ...
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... Micrel, Inc. MIC4724 Schematic and BOM for 3A Output Item Part Number C1a,C1b C2012JB0J106K GRM219R60J106KE19 08056D106MAT C2 0402ZD104MAT C3 C2012JB0J475K GRM188R60J475KE19 06036D475MAT C4 VJ0403A820KXAA D1 SSA33L L1 RLF7030-1R0N6R4 744 778 9001 IHLP2525AH-01 1 R1,R4 CRCW04021002F R2 CRCW04026651F CRCW04021242F CRCW04022002F CRCW04024022F R3 CRCW040210R0F U1 MIC4724YME Notes: 1. TDK: www.tdk.com 2. Murata: www.murata.com 3. AVX: www.avx.com 4. Vishay: www.vishay.com 5 ...
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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 June 2008 10-Pin ePAD MSOP (MME) indemnify Micrel for any damages resulting from such use or sale. © 2008 Micrel, Incorporated. 19 MIC4724 nt M9999-062408-A ...