mic3832 Micrel Semiconductor, mic3832 Datasheet
mic3832
Related parts for mic3832
mic3832 Summary of contents
Page 1
... Current-fed topologies eliminate core saturation problems caused by shoot through (cross conduction) of push-pull circuits and reduce stress on the switching transistors. The MIC3832/3 has one PWM stage capable of operating up to 500kHz and two output stages, Q and Q, that operate at one-half of the system frequency at a fixed 50% duty cycle. ...
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... MIC3832/3833 Pin Description Pin Number Pin Name 1 GND 2 PWM REF 6 EA – OUT SHDN 11 MDC/SS 12 CMR 13 SYNC Pin Function Ground: Use as single-point ground tie point. PWM Output: Variable duty-cycle totem pole output. Q Switch (Output): Totem pole output. Noninverting 50% duty cycle output (180 out-of-phase with Q with no dead time) ...
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... Oscillator Timing Capacitor .............................. 1nF to 10nF = 12V to 20V = 16k , C = 2.2nF 12V to 20V < < 4.5V CM < 20V –0.5mA = 1mA 4-137 Micrel ): MIC3832 ....................... 16V to 21V DD ): MIC3833 ...................... 7.6V to 21V DD to 100k Min Typical Max Units 4.90 5.0 5. –0.2 mV 5.0 ...
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... UVLO Saturation I SINK Overlap Q rising, Q falling, 50 Overlap Q rising, Q falling, 50% Undervoltage Lockout Section Upper Threshold—Startup MIC3832 MIC3833 Lower Threshold—Operating MIC3832 (Shutdown) MIC3833 Total Standby Current Startup Current Operating Supply V Zener Voltage Note 1 Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device beyond its specified Operating Ratings ...
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... Current Sense Threshold vs. Error Amplifier Output 125 - ERROR AMP OUTPUT (V) April 1998 MIC3832 Undervoltage Lockout vs. Junct. Temp. 16.4 16.2 ON 16.0 15.8 15.6 - 120 160 10.0 9.8 9.6 9.4 OFF 9.2 - 120 160 JUNCTION TEMPERATURE ( C) Discharge Time vs. ...
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... MIC3832/3833 Block Diagram V DD 21V 5V REF SYNC R T OSC – EA OUT CMR MDC/SS SHDN GND UVLO LATCH UVLO S REF R 1-SHOT FRONT EDGE BLANKING PWM 1.5V R MDC S PWM LATCH 1.25V 1.0V 4-140 Micrel V DD PWM MIC3832/3833 April 1998 ...
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... Undervoltage lockout (UVLO) requires that the input voltage rise above 15.9V (MIC3832) or 8.3V (MIC3833) before the startup circuit is energized. Once operating, the controller will not shut down until the supply drops to 9.8V (MIC3832) or 7.8V (MIC3833). There is an internal 22V zener between V and ground for overvoltage clamping. Zener current should be limited to less than 20mA ...
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... The MIC3832/3 may be operated in current mode by connect- ing the current sample to the CMR pin. variations affect the inductor current slope, providing fast response ...
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... MIC3832/3833 The push-pull cycles are synchronized to run at half of the PWM frequency soft or zero voltage switch transition may be obtained, reducing spikes and EMI. Feeding a sample of the PWM oscillator ramp to the current-mode comparator along with the input current sample allows slope compensation to be obtained for PWM duty cycles above 50%, preventing subharmonic oscillation at low input volt- ages ...
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... MIC3832/3833 100kHz 100W Current-Fed Converter Refer to Figure 5. A 5V, 20A dc-to-dc converter uses the current-fed, push-pull configuration for increased safety and reduced size and transformer core area. The input is an unregulated 14V to 32Vdc supply. MIC2951 low-dropout regulator supplies 12V to the MIC3833. The main PWM switching element is an IRF540, with gate drive provided by transformer T1 ...