MIC2199 MICREL [Micrel Semiconductor], MIC2199 Datasheet
MIC2199
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MIC2199 Summary of contents
Page 1
... An all N-Channel synchronous architecture and powerful output drivers allow up to 20A of output current capability. For smaller external components, refer to the 500kHz MIC2198. The MIC2199 is available in a 12-pin 4mm × 4mm MLF™ package with a junction temperature range from –40°C to 125°C. Typical Application ...
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... COMP 2 EN/UVLO CSH 5 VOUT 6 VIN 7 VDD 8 LSD 9 GND 10 BST 11 VSW 12 HSD MIC2199 Package –40°C to +125°C 12-lead 4×4 MLF™ COMP EN/UVLO CSH 4 9 VOUT 5 8 VIN 6 7 4× × × × × 4 MLF-12L (ML) Pin Function Compensation (Output): Internal error amplifier output ...
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... Micrel (Note 2) ) ........................ +4.5V to +32V IN ) ........................ +0.8V to +6V OUT ) ....................... –40°C to +125° .............................................. 60°C/W JA Min Typ Max Units 0.792 0.8 0.808 0.784 0.816 0.776 0.824 10 0.8 6 0.03 0.5 1.6 2.5 0.1 5 4.7 5.0 5.3 4.25 4.4 3.95 4.1 0.6 1.1 1.6 2.2 2.5 2.8 0 0.2 270 300 330 80 85 170 200 MIC2199 %/ µ µ kHz % ns ...
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... Exceeding the absolute maximum rating may damage the device. Note 2. The device is not guaranteed to function outside its operating rating. Note 3. Devices are ESD protected; however, handling precautions are recommended. Human body model, 1.5k in series with 100pF. Note 4. Specification for packaged product only. MIC2199 pin OUT = 3000pF 4 Micrel Min ...
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... OUTPUT CURRENT (A) 5 Micrel V FB Line Regulation 0.820 0.818 0.816 0.814 0.812 0.810 0.808 SUPPLY VOLTAGE ( Load Regulation 5.02 5.01 5.00 4.99 4.98 4.97 4.96 4.95 4. LOAD CURRENT (mA) Oscillator Frequency vs. Supply Voltage 0.25 0.20 0.15 0.10 0.05 0.00 -0.05 -0.10 -0. SUPPLY VOLTAGE (V) MIC2199 ...
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... Sampling the inductor current removes the inductor from the control loop, which simplifies compensa- tion. A block diagram of the MIC2199 PWM current-mode control loop is shown in Figure 2 and the PWM mode voltage and current waveform is shown in Figure 3. The inductor current is sensed by measuring the voltage across the resistor, R ...
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... I LOAD Figure 3. PWM-Mode Timing VDD 7 4.7µF VIN D2 6 BST 10 HSD C BST OUT VSW 11 LSD C D1 OUT 8 Q1 PGND 9 CSH 4 VOUT ⎛ ⎞ 0. OUT ⎝ ⎠ R2 Micrel MIC2199 ...
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... The enable pin (pin 2) has two threshold levels, allowing the MIC2199 to shut down in a low current mode, or turn off output switching in UVLO mode. An enable pin voltage lower than the shutdown threshold turns off all the internal circuitry and reduces the input current to typically 0.1µ ...
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... The MIC2199 has a specified minimum pulsewidth. This minimum pulsewidth places a lower limit on the minimum duty cycle of the buck converter. Figure 5 shows the minimum output voltage versus input supply voltage for the MIC2199. For example, for would be the lowest achievable voltage that OUT conforms to the minimum-on-time ...
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... MOSFET power dissipation. Total gate charge is the charge required to turn the MOSFET on and off under specified operating conditions ( The gate charge is supplied by the MIC2199 gate drive GS circuit. At 500kHz switching frequency, the gate charge can be a significant source of power dissipation in the MIC2199. ...
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... × V × G[low-side](avg) ISS GS Since the current from the gate drive comes from the input voltage, the power dissipated in the MIC2199 due to gate drive is GATEDRIVE IN G[high-side](avg) A convenient figure of merit for switching MOSFETs is the on- resistance times the total gate charge (R numbers translate into higher efficiency ...
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... Schottky diode causes less ringing and less power loss. Depending on the circuit components and oper- ating conditions, an external Schottky diode will give a 1/ improvement in efficiency. MIC2199 Output Capacitor Selection The output capacitor values are usually determined by the capacitors ESR (equivalent series resistance). Voltage rating ...
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... The power dissipated in the input capacitor is × R DISS ESR (rms Voltage Setting Components The MIC2199 requires two resistors to set the output voltage as shown in Figure 6. Error Amp V REF 0.8V MIC2199 Figure 6. Voltage-Divider Configuration The output voltage is determined by the equation: ⎛ ⎞ R1 ...
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... Avoid running the traces under the inductor and other switching components. The 10Ω resistor should be placed close as possible to pins 4 and 5 on the MIC2199 and a 1nF to 0.1µF capacitor placed between pins 4 and 5 will help attenuate switching noise on the current sense traces. This capacitor should be placed close to pins 4 and 5 ...
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... Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify November 2004 4× × × × × 4 12-Lead MLF™ (ML (408) 474-1000 FAX WEB Micrel for any damages resulting from such use or sale. © 2004 Micrel, Incorporated. 15 http://www.micrel.com Micrel MIC2199 ...