MIC2182 Micrel Semiconductor, MIC2182 Datasheet
MIC2182
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MIC2182 Summary of contents
Page 1
... The MIC2182 operates from a 4.5V to 32V input and can operate with a maximum duty cycle of 86% for use in low- dropout conditions. It also features a shutdown mode that reduces quiescent current to 0 ...
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... MIC2182 Ordering Information Part Number MIC2182BM MIC2182-3.3BM MIC2182-5.0BM MIC2182BSM MIC2182-3.3BSM MIC2182-5.0BSM Pin Configuration MIC2182 SS 1 PWM 2 COMP 3 SGND 4 SYNC 5 EN/UVLO CSH 8 Adjustable 16-pin SOP (M) 16-Pin SSOP (SM) MIC2182 Voltage Temperature Range Adjustable – +85 C 3.3V – +85 C 5.0V – ...
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... Switch (Return): High side MOSFET driver return. High-Side Drive (Output): High-current driver output for high-side MOSFET. This node voltage swing is between ground and V 3 Micrel pins in conjunction with the OUT is the external MOSFET gate minus a diode drop – diode drop MIC2182 ...
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... ESD, Note 3 Electrical Characteristics V = 15V open 0V PWM SHDN noted Parameter Condition MIC2182 [Adjustable], (Note 5) Feedback Voltage Reference Feedback Voltage Reference Feedback Voltage Reference 4.5V < V Feedback Bias Current Output Voltage Range Output Voltage Line Regulation V IN Output Voltage Load Regulation 25mV < ...
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... OUT(nominal 3000pF = 0V 5 Micrel Min Typ Max Units 1.220 1.245 1.270 0.6 1.1 1.6 V 2.2 2.5 2 –3.5 –5 –6 100 135 mV 20 2.0 270 300 330 kHz 86 % 140 250 ns 0.7 1.3 1 200 ns 330 kHz 0.75 0.95 1. kHz 8.5 3 –10 A MIC2182 ...
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... REF vs. Temperature 1.260 1.255 1.250 1.245 1.240 -40 - 100120140 TEMPERATURE ( vs. Temperature 4.98 4.96 4.94 4.92 4.90 4.88 4.86 4.84 4.82 -40 - 100120140 TEMPERATURE ( C) MIC2182 Quiescent Current vs. Temperature 1.50 1.00 UVLO Mode 0.50 (mA) 0 -0.50 0.20 0.15 0.10 SHUTDOWN 0. -40 - 100120140 TEMPERATURE ( C) V (Fixed Versions) REF Line Regulation 1.256 1 ...
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... MIC2182 Soft-Start Current vs. Temperature 5.0 4.8 4.6 4.4 4.2 4.0 -40 - 100120140 TEMPERATURE ( C) June 2000 Overcurrent Threshold vs. Temperature 0.12 0.11 0.10 0.09 0.08 -40 - 100120140 TEMPERATURE ( C) 7 Micrel Current-Limit Foldback 3.3V OUT R = 15m OUTPUT CURRENT (A) MIC2182 ...
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... MIC2182 Block Diagrams EN/UVLO Control Logic PWM 2 PWM CORRECTIVE RESET RAMP SYNC Oscillator 5 COMP 3 C COMP R COMP MIC2182 [adj.] MIC2182 V DD Reference V IN Current Limit PWM Mode to Skip Mode 0.024V Skip-Mode Current Limit 0.07V Low Comp –2%V BG Hysteresis Comp Current ...
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... V Error Amp 100k - 0 Figure 2b. Fixed Output Voltage Versions VDD 11 4.7 F VIN D2 10 VBST 14 HSD C BST VSW 15 LSD PGND 12 CSH 8 VOUT 9 * 82.5k for 3.3V Output 150k for 5V Output R1* SGND 4 R2 50k VREF 7 Micrel V OUT C OUT MIC2182 ...
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... An internal corrective ramp provides slope compensation for stable operation above a 50% duty cycle. The controller is optimized for high-efficiency, high-performance dc-dc con- verter applications. The MIC2182 block diagrams are shown in Figure 2a and Figure 2b. The MIC2182 controller is divided into 6 functions. • Control loop - PWM operation - Skip-mode operation • ...
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... IC in not switching. The disadvantage of this method is greater output voltage ripple and variable switching frequency. A block diagram of the MIC2182 skip mode is shown in Figure 4. Skip mode voltage and current waveforms are shown in figure 5B. V ...
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... V cycle repeats when V falls below the lower threshold, – OUT 1%. The maximum peak inductor current depends on the skip- mode current-limit threshold and the value of the current- sense resistor 35mV I inductor(peak) R sense MIC2182 LOAD ...
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... The reference voltage in the fixed-output-voltage versions of the MIC2182 is buffered and brought to pin 7. The V (pin 4) with a 0.1 F capacitor. The adjustable version of the MIC2182 uses pin 7 for output voltage sensing. A decoupling capacitor on pin 7 is not used in the adjustable output voltage version. in Figure 2.). The cur- ...
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... MIC2182 The enable pin (pin 6) has two threshold levels, allowing the MIC2182 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 0.1 A. ...
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... A minimum load is required to prevent the output from rising up. This will not occur for output voltages greater than 3V. Figure 11 should be used as a guide when the MIC2182 is forced into PWM-only mode. The actual maximum input voltage will depend on the exact external components used (MOSFETs, inductors, etc ...
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... This change in resistance must be accounted for when calculating 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 MIC2182 gate drive GS circuit. At 300kHz switching frequency and above, the gate 16 2 ...
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... For the low-side MOSFET G[low-side](avg) ISS GS Since the current from the gate drive comes from the input voltage, the power dissipated in the MIC2182 due to gate drive is gate drive 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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... The diode recovery and the TIME Figure 12. Switch Output Noise With and Without Shottky Diode MIC2182 circuit inductance will cause ringing during the high-side MOSFET turn-on. An external Schottky diode conducts at a lower forward 2 voltage preventing the body diode in the MOSFET from turning on ...
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... Use a low gate-charge MOSFET or use the smallest MOSFET, which is still adequate for maximum output current. • Allow the MIC2182 to run in skip mode at lower currents. • Use a ferrite material for the inductor core, which has less core loss than an MPP or iron power core ...
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... MOSFETs turn on and off must be kept away from the small signal connections. • The connection between the current-sense resistor and the MIC2182 current-sense inputs (pin 8 and 9) should have separate traces, routed from the terminals directly to the IC pins. The traces should be routed as closely as possible to each other and their length should be minimized ...
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... Sumida June 2000 Power supplies larger than 10A can also be constructed using the MIC2182 using larger power-handling compo- nents. The “Power Supply Operating Characteristics” graphs follow- ing the component and vendor tables provide useful informa- tion about the actual performance of some of these circuits. ...
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... Si4884, Siliconix, high-side MOSFET high-side MOSFET qty: 1 qty: 1 WSL-2010 .020 1%, WSL-2512 .015 1%, Vishay, 0.02, 1%, 0.5W, Vishay, 0.015, 1%, 1W, current sense resistor current sense resistor MIC2182-3.3BM or MIC2182-3.3BM or MIC2182-3.3BSM MIC2182-3.3BSM Table 4. Components for 3.3V Output 22 Micrel 10A (6.5V–10V) Part No. / Description qty: 2 TPSV337M010R0060 AVX, 330 F 10V, 0 ...
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... Si4800, Siliconix, qty: 1 Si4800, Siliconix, high-side MOSFET high-side MOSFET qty: 1 qty: 1 WSL-2010 .020 1%, WSL-2512 .015 1%, Vishay, 0.02, 1%, 0.5W, Vishay, 0.015, 1%, 1W, current sense resistor current sense resistor MIC2182BSM or MIC2182BSM or MIC2182BM MIC2182BM Table 6. Components for 1.8V Output 23 Micrel 10A (4.5V–5.5V) Part No. / Description qty: 2 TPSV447M006R0055 AVX, 470 F 6.3V, ...
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... Effect of Soft-Start Capacitor (C On Output Voltage Waveforms During Turn-On (10A Power Supply Configuration) Normal (300kHz Switching Frequency) and Output Short-Circuit (60kHz) Conditions Switch Node (Pin 15) Waveforms Typical Skip-Mode Waveforms MIC2182 ) Value SS 24 Effect of Soft-Start Capacitor (C ) Value SS On Output Voltage Waveforms During Turn-On ...
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... OUT 7.5m Bode Plot (10A Power Supply Configuration) 100 210 80 180 60 150 GAIN 40 120 PHASE -20 30 -40 0 FREQUENCY (Hz) Efficiency (10A Power Supply Configuration) 100 Skip 80 PWM 7. 3 high-side MOSFETs: Si4884 2 low-side MOSFETs: Si4884 0 0.01 0 OUTPUT CURRENT (A) MIC2182 ...
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... MIC2182 Package Information 0.157 (3.99) 0.150 (3.81) 0.020 (0.51) REF 0.0648 (1.646) 0.0434 (1.102) 6.33 (0.239) 6.07 (0.249) 0.38 (0.015) 0.25 (0.010) 0.65 (0.0260) BSC MIC2182 PIN 1 0.020 (0.51) 0.050 (1.27) BSC 0.013 (0.33) 0.0098 (0.249) 0.0040 (0.102) 0.394 (10.00) 0.386 (9.80) SEATING PLANE 16-pin SOP (M) 5.40 (0.213) 5.20 (0.205) 7.90 (0.311) 7.65 (0.301) 0.875 (0.034) REF 2.00 (0.079) 1 ...
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... MIC2182 June 2000 27 Micrel MIC2182 ...
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... This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. MIC2182 + 1 (408) 944-0970 http://www ...