MIC2168A Micrel Semiconductor, MIC2168A Datasheet
MIC2168A
Related parts for MIC2168A
MIC2168A Summary of contents
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... General Description The MIC2168A is a high-effi ciency, simple to use 1MHz PWM synchronous buck control IC housed in a small MSOP-10 package. The MIC2168A allows compact DC/DC solutions with a minimal external component count and cost. The MIC2168A operates from 14.5V input, without the need of any additional bias voltage. The output voltage can be precisely regulated down to 0.8V. The adaptive all N-Channel MOSFET drive scheme allows effi ...
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... MIC2168A Ordering Information Part Number Standard Pb-Free MIC2168ABMM MIC2168AYMM www.DataSheet4U.com Pin Confi guration Pin Description Pin Number Pin Number Pin Number Pin Number Pin Name Pin Name Pin Name Pin Name VIN VIN VIN VDD VDD VDD ...
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... MIC2168A Absolute Maximum Ratings Supply Voltage (V ) ................................................... 15.5V IN Booststrapped Voltage (V ) .................................V BST Junction Temperature (T ) ...................–40°C ≤ www.DataSheet4U.com Storage Temperature (T ) ........................ –65°C to +150 °C S Electrical Characteristics T = 25° 5V, unless otherwise specifi ed. Bold values indicate –40°C < Parameter ...
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... MIC2168A Electrical Characteristics Parameter Parameter Parameter Parameter Parameter Parameter Condition Condition Condition Condition Condition Condition Error Amplifi Gain DC Gain DC Gain DC Gain DC Gain DC Gain www.DataSheet4U.com Transconductance Transconductance Transconductance Transconductance Transconductance Transconductance Soft-Start Soft-Start Current Soft-Start Current After timeout of internal timer. See After timeout of internal timer. See “ ...
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... MIC2168A Typical Characteristics PWM Mode Supply Current www.DataSheet4U.com vs. Temperature 2.9 2.7 2.5 2.3 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 -40 - 100 120 140 TEMPERATURE (°C) V vs. Temperature FB 0.820 0.815 0.810 0.805 0.800 0.795 0.790 0.785 0.780 -60 - 120 150 TEMPERATURE (°C) V Line Regulation DD vs. Temperature 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 -60 -30 ...
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... This will cause the PWM comparator to increase t the top side MOSFET, causing the output voltage and bringing V Soft-Start The COMP/EN pin on the MIC2168A is used for the following three functions: 1. Disables the part by grounding this pin 2. External compensation to stabilize the voltage control loop 3 ...
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... MOSFET Gate Drive The MIC2168A high-side drive circuit is designed to switch an N-Channel MOSFET. The block diagram in Figure 2 shows a bootstrap circuit, consisting of D2 and CBST, supplies energy to the high-side drive circuit. Capacitor CBST is charged while the low-side MOSFET is on and the voltage on the VSW pin is approximately 0V ...
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... G[low G[low -side](avg) side](avg) ISS ISS ISS GS GS Since the current from the gate drive comes from the input voltage, the power dissipated in the MIC2168A due to gate drive is ...
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... Maximizing effi ciency requires the proper selection of core material and minimizing the winding resistance. The high frequency operation of the MIC2168A requires the use of ferrite materials for all but the most cost sensitive applica- tions. Lower cost iron powder cores may be used but the increase in core loss will reduce the effi ...
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... ESR (rms) C (rms) C (rms) www.DataSheet4U.com IN IN Voltage Setting Components The MIC2168A requires two resistors to set the output volt- age as shown in Figure 2. Error Amp V REF 0.8V MIC2168 [adj.] Figure 2. Voltage-Divider Confi guration Where: V for the MIC2168A is typically 0.8V REF The output voltage is determined by the equation: ...
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... Figure 4, versus 105° for Figure 6. The simple RC and C2 compensation scheme allows a maximum error amplifi er phase boost of about 90°. Therefore easier to stabilize the MIC2168A voltage control loop by using high ESR value output capacitors. g Error Amplifi undesirable to have high error amplifi ...
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... Figure 8. Error Amplifi er Phase Curve Total Open-Loop Response The open-loop response for the MIC2168A controller is easily obtained by adding the power path and the error amplifi er gains together, since they already are in Log scale desirable to have the gain curve intersect zero dB at tens of kilohertz, this is commonly called crossover frequency ...
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... The compensation resistor and capacitors should be placed right next to the COMP/EN pin and the other side should connect directly to the GND pin on the MIC2168A rather than going to the plane. 5. The input bulk capacitors should be placed close to the drain of the top MOSFET. ...
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... MIC2168A Package Information www.DataSheet4U.com MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA + 1 (408) 944-0800 TEL This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifi cations at any time without notifi cation to the customer. ...