MIC26901 MICREL [Micrel Semiconductor], MIC26901 Datasheet
MIC26901
Related parts for MIC26901
MIC26901 Summary of contents
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... ON advantages of fixed-frequency operation and fast transient response in a single device. The MIC26901 offers a full suite of protection features to ensure protection of the IC during fault conditions. These include undervoltage lockout to ensure proper operation under power-sag conditions, internal soft-start to reduce inrush current, foldback current limit, “ ...
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... Range −40°C to +125°C 600kHz 28-Pin 5mm × 6mm MLF ® . When Package 28-Pin 5mm × 6mm MLF (YJL) < +5.5V, PVDD should be tied to PVIN pins. A 2.2µF IN must be place next to the IC. operating voltage range is from IN MIC26901 Lead Finish ® Pb-Free M9999-071311-A ...
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... Internal Linear Regulator (Output): VDD supply is the power MOSFET gate drive supply voltage and the supply bus for the IC. VDD is created by internal LDO from V 28 VDD should be tied to PVIN pins. A 1.0µF ceramic capacitor from the VDD pin to PGND pins must be place next to the IC. July 2011 > 92% of nominal. OUT 3 MIC26901 < +5.5V, VDD . When M9999-071311-A ...
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... T ≤ 125°C (±1.5 (Continuous Mode) OUT V = 4.5V to 28V 0. 12V 1. MIC26901 ( )............................... 4.5V to 28V )......... 4. .................................................. ........................ −40°C to +125°C J (4) ® (θ ) .....................................28°C/W JA ≤ +125°C. J Min. Typ. ...
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... Low to High FB < 0.9 × V Sweep 1mA FB NOM PG T Rising J depends upon the printed circuit layout square inch 4 layer, 0.62”, FR-4 PCB with 2oz finish copper weight of typically 300ns. OFF 5 MIC26901 ≤ +125°C. J Min. Typ. Max. Units 11. ...
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... Input Voltage INPUT VOLTAGE (V) Current Limit vs. Input Voltage INPUT VOLTAGE (V) PG/V REF vs. Input Voltage 100% 95% 90% 85% 80 4.0 10.0 INPUT VOLTAGE (V) MIC26901 10mA 1.8V OUT Ratio V = 0.7V REF 16.0 22.0 28.0 M9999-071311-A ...
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... TEMPERATURE (°C) Line Regulation vs. Temperature 0.2% 0.1% 0.0% -0.1% -0.2% 75 100 125 -50 - TEMPERATURE (°C) Current Limit vs. Temperature 100 125 -50 - TEMPERATURE (°C) MIC26901 50 75 100 125 V = 4.5V to 28V 1.8V OUT OUT 50 75 100 125 V = 12V 1.8V OUT 50 75 100 125 M9999-071311-A ...
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... OUTPUT CURRENT (A) Output Voltage (V vs. Output Current 5.0 4.6 4.2 3.8 3.4 3 OUTPUT CURRENT (A) Die Temperature* (V vs. Output Current 100 1 OUTPUT CURRENT (A) MIC26901 V = 12V 1.8V OUT 4 < 0. 25ºC 85ºC 125º 5V) ...
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... OUTPUT CURRENT (A) Thermal Derating* vs. Ambient Temperature 12V 0.8, 1.2, 1.8V OUT 100 125 -50 - AMBIENT TEMPERATURE (°C) MIC26901 = 12V 12V 1.8V OUT 24V 24V 1.8V OUT 0.8V 1. 100 125 M9999-071311-A ...
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... AMBIENT TEMPERATURE (°C) Die Temperature* : The temperature measurement was taken at the hottest point on the MIC26901 case mounted square inch 4 layer, 0.62”, FR-4 PCB with 2oz finish copper weight per layer, see Thermal Measurement section. Actual results will depend upon the size of the PCB, ambient temperature and proximity to other heat emitting components ...
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... Micrel, Inc. Functional Characteristics July 2011 11 MIC26901 M9999-071311-A ...
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... Micrel, Inc. Functional Characteristics (Continued) July 2011 12 MIC26901 M9999-071311-A ...
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... Micrel, Inc. Functional Characteristics (Continued) July 2011 13 MIC26901 M9999-071311-A ...
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... Micrel, Inc. Functional Diagram July 2011 Figure 1. MIC26901 Block Diagram 14 MIC26901 M9999-071311-A ...
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... MOSFET. July 2011 The maximum duty cycle is obtained from the 300ns t OFF(min) where not recommended to use MIC26901 with a OFF-time close OUT and reduce the line regulation performance. Therefore, the maximum output voltage of the MIC26901 should be limited to 5.5V and the maximum external ripple injection should be limited to 200mV. Please refer to “ ...
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... Micrel, Inc. Figure 2. MIC26901 Control Loop Timing Figure 3 shows the operation of the MIC26901 during a load transient. The output voltage drops due to the sudden load increase, which causes the V than V . This will cause the error comparator to trigger REF an ON-time period. At the end of the ON-time period, a ...
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... FEEDBACK VOLTAGE (V) Figure 4. MIC26901 Current-Limit Foldback Characteristic Power Good (PG) The Power Good (PG) pin is an open drain output which indicates logic high when the output is nominally 92% of its steady state voltage. A pull-up resistor of more than 10kΩ should be connected from PG to VDD. ...
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... July 2011 Maximizing efficiency requires the proper selection of core material and minimizing the winding resistance. The high frequency operation of the MIC26901 requires the use of ferrite materials for all but the most cost sensitive applications. Lower cost iron powder cores may be used but the increase in core loss will reduce the efficiency of the power supply ...
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... If the feedback voltage ripple is so small that the g then the MIC26901 will lose control and the output voltage is not regulated. In order to have some amount of V output voltage ripple applications. ...
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... Power stage input voltage = switching frequency ) × C inj ff must be much greater than << 1 × τ τ 1nF to 100nF can easily satisfy the large ff is used in order to be considered as short inj MIC26901 and a inj 1 × Eq τ × Eq. 19 Eq. 20 M9999-071311-A ...
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... July 2011 is 1nF addition to the external ripple injection added at the FB pin, internal ripple injection is added at the inverting input of the comparator inside the MIC26901, as shown − in Figure 8. The inverting input voltage V 1) Eq. 22 1.2V clamped. The clamped V because it is reflected error on the FB terminal. ...
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... ICs. However thermometer from Optris has a 1mm spot size, which makes it a good choice for measuring the hottest point on the case. An optional stand makes it easy to hold the beam on the IC for long periods of time. July 2011 thermometer is 22 MIC26901 M9999-071311-A ...
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... 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 MIC26901 regulator. IC • A 2.2µF ceramic capacitor, which is connected to the PVDD pin, must be located right at the IC. The PVDD pin is very noise sensitive and placement of the capacitor is very critical ...
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... Micrel, Inc. Evaluation Board Schematic July 2011 Figure 8. Schematic of MIC26901 Evaluation Board (J11, R13, R15 are for testing purposes) 24 MIC26901 M9999-071311-A ...
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... Resistor, Size 0603, 1% (7) Vishay Dale 2.00kΩ Resistor, Size 0603, 1% (7) Vishay Dale 1.18kΩ Resistor, Size 0603, 1% (7) Vishay Dale 806Ω Resistor, Size 0603, 1% (7) Vishay Dale 475Ω Resistor, Size 0603 MIC26901 Qty ...
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... Micrel, Inc.: www.micrel.com. July 2011 Manufacturer Description (7) Vishay Dale 0Ω Resistor, Size 0603, 5% (7) Vishay Dale 49.9Ω Resistor, Size 0603, 1% (7) Vishay Dale 1.21Ω Resistor, Size 0603, 1% 28V, 9A Hyper Speed Control ™ Synchronous (9) Micrel. Inc. DC/DC Buck Regulator 26 MIC26901 Qty M9999-071311-A ...
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... Micrel, Inc. PCB Layout Recommendations Figure 10. MIC26901 Evaluation Board Mid-Layer 1 (Ground Plane) July 2011 Figure 9. MIC26901 Evaluation Board Top Layer 27 MIC26901 M9999-071311-A ...
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... Micrel, Inc. PCB Layout Recommendations (Continued) July 2011 Figure 11. MIC26901 Evaluation Board Mid-Layer 2 Figure 12. MIC26901 Evaluation Board Bottom Layer 28 MIC26901 M9999-071311-A ...
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... Micrel, Inc. Recommended Land and Solder Stencil Pattern July 2011 29 MIC26901 M9999-071311-A ...
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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 July 2011 28-Pin 5mm × 6mm MLF indemnify Micrel for any damages resulting from such use or sale. © 2011 Micrel, Incorporated. 30 ® (YJL) http://www.micrel.com MIC26901 nt M9999-071311-A ...