MIC2176-2YMM Micrel Inc, MIC2176-2YMM Datasheet
MIC2176-2YMM
Specifications of MIC2176-2YMM
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MIC2176-2YMM Summary of contents
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... This digitally modified adaptive t ON combines the advantages of fixed-frequency operation and fast transient response in a single device. The MIC2176 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, fold-back current limit, “ ...
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... Micrel, Inc. Ordering Information Output Part Number Voltage MIC2176-1YMM Adjustable MIC2176-2YMM Adjustable MIC2176-3YMM Adjustable Pin Configuration Pin Description Pin Pin Name Pin Function Number High-Side MOSFET Drain Connection (Input): The HSD pin in the input of the adaptive On-time 1 HSD control circuitry. A 0.1uF ceramic capacitor between the HSD pin and the power ground (PGND) is required and must be place as close as possible to the IC ...
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... VDD pin and the BST pin. A boost capacitor of 0.1μF is connected 10 BST between the BST pin and the SW pin. Adding a small resistor in series with the BST pin can slow down the turn-on time of high-side N-Channel MOSFETs. November 2010 3 MIC2176 M9999-111710-A ...
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... T ≤ 125°C (±1.5 0.8V FB 4.5V < V < 5.5V DD 4.5V < V < 5. MIC2176-1 MIC2176-2 MIC2176-3 MIC2176- 0V, HSD=4V MIC2176- 0V, HSD=4V MIC2176- 0V, HSD=4V > 0. (3) ) ....................................... 4.5V to 75V HSD )............................................ 4. ................................................. ........................ −40°C to +125°C J MSOP (θ ) ..................................................130.5°C 70°C) ........................................................421mW A ≤ +125°C. J Min ...
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... MOSFETs have enough low voltage typically 360ns. OFF 5 ≤ +125°C. J Min. Typ. 6 130 103 0. 0.1V BST 2.1 1.8 1.8 1.2 = 53V = 53V 160 25 MIC2176 Max. Units ms mV 162 0.1 V Ω 3.3 Ω 3.3 Ω 3.3 Ω 2.3 µA 55 µA 55 °C ° M9999-111710-A ...
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... IN vs. Input Voltage INPUT VOLTAGE (V) Total Regulation vs. Input Voltage 1.0% V OUT 0. OUT 0.6% 0.4% 0.2% 0. INPUT VOLTAGE ( Operating Supply Current DD vs. Input Voltage INPUT VOLTAGE (V) Current Limit vs. Input Voltage INPUT VOLTAGE (V) MIC2176 MIC2176 3.3V OUT OUT SWITCHING 1.2V OUT M9999-111710-A ...
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... OUT = -50 -20 10 100 130 TEMPERATURE (°C) Line Regulation vs. Temperature 1.0% 0.8% = 48V = 3.3V 0. 0.4% 0.2% 0.0% -0.2% -50 -20 10 100 130 TEMPERATURE (°C) = 48V 100 130 MIC2176 Rising V = 48V 100 130 40 70 100 130 70V 3.3V OUT OUT 100 130 M9999-111710-A ...
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... OUTPUT CURRENT (A) Case Temperature* : The temperature measurement was taken at the hottest point on the MIC2176 case mounted square inch PCB, 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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... Efficiency (V = 48V) IN vs. Output Current MIC2176-2 VDD = 5V LINEAR OUTPUT CURRENT (A) 9 Efficiency (V vs. Output Current 90 5.0V 85 3.3V 80 2.5V 75 1.8V 70 1.5V 1.2V 65 1.0V 60 0. OUTPUT CURRENT (A) MIC2176 = 60V) IN 5.0V 3.3V 2.5V 1.8V 1.5V 1.2V 1.0V 0.9V 0.8V MIC2176-2 VDD = 5V LINEAR M9999-111710-A ...
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... Micrel, Inc. Functional Characteristics November 2010 10 MIC2176 M9999-111710-A ...
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... Micrel, Inc. Functional Characteristics (Continued) November 2010 11 MIC2176 M9999-111710-A ...
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... Micrel, Inc. Functional Characteristics (Continued) November 2010 12 MIC2176 M9999-111710-A ...
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... Micrel, Inc. Functional Diagram November 2010 Figure 1. MIC2176 Functional Diagram 13 MIC2176 M9999-111710-A ...
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... With this assumption, the inverting input of the error comparator is the same as the feedback voltage. ON Figure 2 shows the MIC2176 control loop timing during steady-state operation. During steady-state, the g amplifier senses the feedback voltage ripple, which is proportional to the output voltage ripple plus injected (1) voltage ripple, to trigger the ON-time period ...
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... Micrel, Inc. Figure 3 shows the operation of the MIC2176 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 minimum OFF-time t ...
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... MOSFET to accurately sense the MOSFETs R . DS(ON) November 2010 MOSFET Gate Drive The MIC2176 high-side drive circuit is designed to switch an N-Channel MOSFET. Figure 1 shows a bootstrap circuit, consisting Schottky diode is (3) recommended) and C the high-side drive circuit. Capacitor C while the low-side MOSFET is on and the voltage on the SW pin is approximately 0V ...
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... R DS(ON Duty Cycle = ISS = × × I (avg G[low - side] ISS GS , the power dissipated in the MIC2176 due to gate = × (avg) DD G[high- side] DS(ON) Voltage rating On-resistance Total gate charge . A safety factor of 20% should be added to HSD (max) of the MOSFETs to account for voltage ...
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... Maximizing efficiency requires the proper selection of core material and minimizing the winding resistance. The high frequency operation of the MIC2176 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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... WINDING As described in the “Theory of Operation” subsection in Functional Description , the MIC2176 requires at least 20mV peak-to-peak ripple at the FB pin to make the g amplifier and the error comparator behave properly. Also, the output voltage ripple should be in phase with the (19) inductor current. Therefore, the output voltage ripple ...
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... November 2010 less than 20mV. If the feedback voltage ripple is so small that the g then the MIC2176 will lose control and the output voltage is not regulated. In order to have some amount of V ripple, a ripple injection method is applied for low output voltage ripple applications. ...
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... FB(pp × K div × − obtained as: inj 1 = × − R (R1//R2 inj K div as 100nF, which could be considered inj M9999-111710-A MIC2176 is 1nF to ff (34) (35) ...
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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 MIC2176 converter. IC • The 1µF ceramic capacitor, which is connected to the VDD pin, must be located right at the IC. The VDD pin is very noise sensitive and placement of the capacitor is very critical ...
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... Micrel, Inc. Evaluation Board Schematic November 2010 Figure 7. Schematic of MIC2176 Evaluation Board (J1, J9, J12, R12, and R13 are for testing purposes) 23 MIC2176 M9999-111710-A ...
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... Vishay Dale 10kΩ Resistor, Size 0603, 1% (7) Vishay Dale 1.21Ω Resistor, Size 0805, 5% (7) Vishay Dale 80.6kΩ Resistor, Size 0603, 1% (7) Vishay Dale 40.2kΩ Resistor, Size 0603, 1% (7) Vishay Dale 20kΩ Resistor, Size 0603 MIC2176 Qty ...
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... R8 CRCW06038K06FKEA R9 CRCW06034K75FKEA R10 CRCW06033K24FKEA R11 CRCW06031K91FKEA R12 CRCW060349K24FKEA R13, R21 CRCW06030000FKEA R14 CRCW08059K7FKEA U1 MIC2176-2YMM Notes: 8. Micrel, Inc.: www.micrel.com. November 2010 Manufacturer Description (7) Vishay Dale 11.5kΩ Resistor, Size 0603, 1% (7) Vishay Dale 8.06kΩ Resistor, Size 0603, 1% (7) Vishay Dale 4.75kΩ Resistor, Size 0603, 1% ...
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... Micrel, Inc. PCB Layout November 2010 Figure 8. MIC2176 Evaluation Board Top Layer 26 MIC2176 M9999-111710-A ...
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... Micrel, Inc. PCB Layout (Continued) Figure 9. MIC2176 Evaluation Board Mid-Layer 1 (Ground Plane) November 2010 27 MIC2176 M9999-111710-A ...
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... Micrel, Inc. PCB Layout (Continued) November 2010 Figure 10. MIC2176 Evaluation Board Mid-Layer 2 28 MIC2176 M9999-111710-A ...
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... Micrel, Inc. PCB Layout (Continued) November 2010 Figure 11. MIC2176 Evaluation Board Bottom Layer 29 MIC2176 M9999-111710-A ...
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... Micrel, Inc. Recommended Land Pattern November 2010 30 MIC2176 M9999-111710-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 November 2010 10-Pin MSOP (MM) indemnify Micrel for any damages resulting from such use or sale. © 2010 Micrel, Incorporated. 31 http://www.micrel.com M9999-111710-A MIC2176 nt ...