MIC2177 Micrel Semiconductor, MIC2177 Datasheet
MIC2177
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MIC2177 Summary of contents
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... The output is protected with pulse-by-pulse current limiting and thermal shutdown. Undervoltage lockout turns the output off when the input voltage is less than 4.5V. The MIC2177 is packaged in a 20-lead wide power SO package with an operating temperature range of – +85 C. See the MIC2178 for externally selected PWM or skip-mode operation ...
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... Pin Description Pin Number Pin Name VIN 3,8 SW 4,5,6,7 PGND 10 OUT 11 AUTO COMP 14,15,16,17 SGND 18 SYNC 19 BIAS 20 EN MIC2177 Output Switching Temperature Voltage Frequency Range 3.3V 200kHz – +85 C 5.0V 200kHz – +85 C adj. 200kHz – +85 C VIN VIN 2 19 BIAS SW ...
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... Condition PWM mode, output not switching, 4.5V V 16.5V IN skip mode, output not switching, 4.5V V 16. 0V, 4.5V V 16. 16.5V IN MIC2177 [adj.]: V = 3.3V, I OUT MIC2177 [adj.]: V = 3.3V, OUT 5V V 16V, 10mA IN MIC2177-5. LOAD MIC2177-5. 16V, 10mA IN MIC2177-3. LOAD MIC2177-3. 16V, 10mA IN upper threshold lower threshold MIC2177 [adj ...
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... MIC2177 Symbol Parameter Enable Threshold I Enable Leakage EN AUTO Threshold AUTO Source Current Minimum Switch Current for PWM Operation General Note: Devices are ESD sensitive. Handling precautions recommended. MIC2177 Condition 5. 1.5V, V < 0.8V FB AUTO V – OUT V – OUT 4 Micrel ...
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... TEMPERATURE ( C) PWM-Mode Supply Current 12 OUTPUT 10 SWITCHING INPUT VOLTAGE (V) April 1999 Reference Voltage vs. Temperature 1.252 MIC2177 [adj.] 1.250 1.248 1.246 1.244 1.242 1.240 1.238 -60 - 120 150 TEMPERATURE ( C) Error-Amplifier Gain vs. Temperature 19.0 18.5 18.0 17.5 17.0 16.5 16.0 -60 -30 ...
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... Enable Regulator Shutdown 20 BIAS 19 0.01µF internal supply voltage SYNC 200kHz Oscillator 18 AUTO Auto-Mode PWM 11 2.2nF COMP MIC2177 [Adjustable] C MIC2177 Output I SENSE Control Amp. Logic I LIMIT Comp. PWM/ I MIN Skip-Mode Comp. Select Logic I MIN Thrshld. CORRECTIVE RAMP 3.3V Low Output Comp. ...
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... C. Shutdown Mode The MIC2177 has a low-current shutdown mode that is controlled by the enable input (EN). When a logic 0 is applied to EN, the MIC2177 is in shutdown mode and its quiescent current drops to less than 5 A. Internal Bias Regulator An internal 3.3V regulator provides power to the MIC2177 control circuits ...
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... L1. This IN OUT External PWM-Mode Selection The MIC2177 can be forced to operate in only PWM mode by connecting AUTO to ground. This prevents skip-mode opera- tion in applications that are sensitive to switching noise. 8 drops below a minimum value. I LOAD ) is less than 420mA. This is done by the ...
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... MIC2177 PWM-Mode Functional Diagram SYNC 200kHz Stop Oscillator 18 COMP MIC2177 [Adjustable] PWM-Mode Signal Path V SW Reset Pulse I LOAD I L1 Error Amp. Output I SENSE April 1999 Corrective Ramp Reset Pulse R Q PWM S Comp. Error Amp. V 1.245V REF SGND ...
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... MIC2177 Skip-Mode Functional Diagram Output Control Logic MIC2177 [Adjustable] Skip-Mode Signal Path OUT One-Shot Pulse I LIM 5mV REF – 5mV REF MIC2177 4.5V to 16.5V VIN 100m P-channel One Shot I SENSE Amp. I LIMIT Comp. I LIMIT Thresh. Voltage Skip-Mode Comp ...
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... Application Information Feedback Resistor Selection (Adjustable Version) The output voltage is configured by connecting an external resistive divider to the FB pin as shown in “MIC2177 Block Diagram.” The ratio determines the output voltage. To optimize efficiency during low output current operation, R2 should not be less than 20k . However, to prevent feedback error due to input bias current at the FB pin, R2 should not be greater than 100k ...
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... BIAS pin bypass capacitor should be located near their respective pins. To prevent ground bounce, their ground traces and SGND should not be in the path of switching V IN 4.5V to 16.5V Figure 1. MIC2177 4.5V–16.5V to 3.3/1A Regulator Suggested Manufacturers List Inductors Capacitors Coilcraft AVX Corp. 1102 Silver Lake Rd. ...
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... TYP 0.015 R (0.381) 0.015 0.509 (12.929) (0.381) 0.505 (12.827) MIN SEATING PLANE 20-Lead Wide SOP (WM) 13 DIMENSIONS: INCHES (MM) 0.297 (7.544) 0.293 (7.442) 0.022 (0.559) 7 0.018 (0.457) 5 0.330 (8.382) TYP 0.326 (8.280) 10 TYP 0.032 (0.813) TYP 0.408 (10.363) 0.404 (10.262) Micrel MIC2177 ...
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... MIC2177 MIC2177 14 Micrel April 1999 ...
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... MIC2177 April 1999 15 Micrel MIC2177 ...
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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. MIC2177 + 1 (408) 944-0970 http://www ...