MIC26903 MICREL [Micrel Semiconductor], MIC26903 Datasheet
MIC26903
Related parts for MIC26903
MIC26903 Summary of contents
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... The MIC26903 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, thermal shutdown, internal soft-start to reduce the inrush current, foldback current limit and “hiccup mode” short-circuit protection. The MIC26903 includes a Power Good (PG) output to allow simple sequencing ...
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... MOSFET drain. Due to the high speed switching on this pin, the SW pin should be routed away from sensitive nodes. Power Ground. PGND is the ground path for the MIC26903 buck converter power stage. The PGND pins connect to the low-side N-Channel internal MOSFET gate drive supply ground, the ...
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... Internal Linear Regulator (Output): VDD supply is the supply bus for the IC control circuit. VDD is created by internal LDO from V 28 VDD ceramic capacitor from the VDD pin to SGND pins July 2011 > 92% of nominal. OUT < +5.5V, VDD should be tied to PVIN pins. A 1.0µF . When must be place next to the IC. 3 MIC26903 M9999-071311-A ...
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... T ≤ 125°C (±1.5 (Continuous Mode) OUT V = 4.5V to 28V 0. 12V 1. MIC26903 ( )................................. 4.5V to 28V )......... 4. .................................................. ........................ −40°C to +125°C J (4) ® -24L (θ ) .............................28°C/W JA ≤ +125°C. J Min. ...
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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 MIC26903 ≤ +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% IN 95% 90% 85% 80% 4.0 10 INPUT VOLTAGE (V) MIC26903 10mA 1.8V OUT Ratio V = 0.7V REF 16.0 22.0 28.0 M9999-071311-A ...
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... Line Regulation vs. Temperature 0.2% 0.1% 0.0% -0.1% -0.2% -50 - 100 125 TEMPERATURE (°C) Current Limit vs. Temperature -50 - 100 125 TEMPERATURE (°C) MIC26903 50 75 100 125 V = 4.5V to 28V 1.8V OUT OUT 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 7.5 9 OUTPUT CURRENT (A) Die Temperature* (V vs. Output Current 100 0. 7.5 9 OUTPUT CURRENT (A) MIC26903 V = 12V 1.8V OUT 4 < 0. 25ºC 85ºC 125º 5V) IN ...
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... OUTPUT CURRENT (A) Thermal Derating* vs. Ambient Temperature 12V 0.8, 1.2, 1.8V OUT 2 0 -50 - 100 125 AMBIENT TEMPERATURE (°C) MIC26903 = 12V 12V 1.8V OUT 24V 24V 1.8V OUT 0.8V 1. 100 125 ...
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... AMBIENT TEMPERATURE (°C) Die Temperature* : The temperature measurement was taken at the hottest point on the MIC26903 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 MIC26903 M9999-071311-A ...
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... Micrel, Inc. Functional Characteristics (Continued) July 2011 12 MIC26903 M9999-071311-A ...
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... Micrel, Inc. Functional Characteristics (Continued) July 2011 13 MIC26903 M9999-071311-A ...
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... Micrel, Inc. Functional Diagram July 2011 Figure 1. MIC26903 Block Diagram 14 MIC26903 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 MIC26903 with a OFF-time close OUT and reduce the line regulation performance. Therefore, the maximum output voltage of the MIC26903 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. MIC26903 Control Loop Timing Figure 3 shows the operation of the MIC26903 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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... In each switching cycle of the MIC26903 converter, the inductor current is sensed by monitoring the low-side MOSFET in the OFF period. If the inductor current is greater than 15A, then the MIC26903 turns off the high- side MOSFET and a soft-start sequence is triggered. This mode of operation is called “hiccup mode” and its purpose is to protect the downstream load in case of a hard short ...
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... D1. An approximate 30ns delay between the high-side and low-side driver transitions is used to prevent current from simultaneously flowing unimpeded through both MOSFETs. . Diode recharged through , can BST 18 – where V is the voltage drop across DIODE DIODE MIC26903 supply voltage. DD and the DD M9999-071311-A ...
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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 MIC26903 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 MIC26903 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 << × τ τ 1nF to 100nF can easily satisfy the large ff is used in order to be considered as short inj MIC26903 and a inj × Eq × τ SW Eq. 19 Eq. 20 M9999-071311-A ...
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... R (R1//R2) ( inj K div Step 3. Select C as 100nF, which could be considered inj as short for a wide range of the frequencies. Setting Output Voltage The MIC26903 requires two resistors to set the output voltage as shown in Figure 7. The output voltage is determined by the equation × OUT FB R2 where ...
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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 23 MIC26903 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 MIC26903 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 9. Schematic of MIC26903 Evaluation Board (J11, R13, R15 are for testing purposes) 25 MIC26903 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 MIC26903 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 Light Load ™ Synchronous (9) Micrel. Inc. DC/DC Buck Regulator 27 MIC26903 Qty M9999-071311-A ...
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... Micrel, Inc. PCB Layout Figure 11. MIC26903 Evaluation Board Mid-Layer 1 (Ground Plane) July 2011 Figure 10. MIC26903 Evaluation Board Top Layer 28 MIC26903 M9999-071311-A ...
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... Micrel, Inc. PCB Layout (Continued) July 2011 Figure 12. MIC26903 Evaluation Board Mid-Layer 2 Figure 13. MIC26903 Evaluation Board Bottom Layer 29 MIC26903 M9999-071311-A ...
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... Micrel, Inc. Recommended Land and Solder Stencil Pattern July 2011 30 MIC26903 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. 31 ® (YJL) http://www.micrel.com MIC26903 nt M9999-071311-A ...