MIC38C42 Micrel Semiconductor, MIC38C42 Datasheet
MIC38C42
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MIC38C42 Summary of contents
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... MIC38C4x-1 (14-lead) versions only * MIC38C4x (8-lead) versions only † MIC38C42, MIC38C43 (96% max. duty cycle) versions only ‡ MIC38C44, MIC38C45 (50% max. duty cycle) versions only MM8 is a trademark of Micrel, Inc. Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com ...
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... MIC38C43-1BN MIC38C44-1BN MIC38C45-1BN MIC38C42BM MIC38C43BM MIC38C44BM MIC38C45BM MIC38C42BMM MIC38C43BMM MIC38C44BMM MIC38C45BMM MIC38C42-1BM MIC38C43-1BM MIC38C44-1BM MIC38C45-1BM Refer to the Part Number Cross Reference for a listings of Micrel devices equivalent to UC284x and UC384x devices. Selection Guide Duty Cycle 50% MIC38C42/3/4/5 Temperature Range Package – ...
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... Power Supply (Input): P-channel driver transistor supply input. Return to power ground (PGND). VDD Analog Supply (Input): Controller circuitry supply input. Return to analog ground (AGND). NC Not internally connected. VREF 5V Reference (Output): Connect external RC network. 3 Micrel 14-Pin DIP (-1BN) 14-Lead SOIC (-1BM) MIC38C42/3/4/5 ...
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... Output Source Current High V OUT FB V Low V OUT FB MIC38C42/3/4/5 Operating Ratings Junction Temperature (T Package Thermal Resistance 8-Pin Plastic DIP (θ 8-Pin MM8™ (θ 8-Pin SOIC (θ 14-Pin Plastic DIP (θ 14-Pin SOIC (θ ≤ 85°C; unless noted A = 25° 1mA O ≤ ...
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... DD Note 5: Output frequency equals oscillator frequency for the MIC38C42 and MIC38C43. Output frequency for the MIC38C44, and MIC38C45 equals one half the oscillator frequency. Note 6: On 8-pin version, 20V is maximum input on pin 7, as this is also the supply pin for the output stage. On 14-pin version, 40V is maximum for pin 12 and 20V maximum for pin 11 ...
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... OSCILLATOR FREQUENCY (Hz) Current Sense Amplifier vs. Error Amplifier Output 1.2 1.0 125°C 0.8 0.6 25°C 0.4 -50°C 0.2 0 ERROR AMPLIFIER OUTPUT (V) MIC38C42/3/4/5 MIC38C42/43 Output Dead Time vs. Oscillator Frequency 100 V = 15V DD 4.7nF 10 200pF 10nF 470pF 1nF 18nF 1x10 1x10 1x10 FREQUENCY (Hz) Short-Circuit Reference Current vs ...
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... Buck Converter Refer to figure 1. When at least 26V is applied to the input charged through R2 until the voltage V 14.5V (the undervoltage lockout value of the MIC38C42). Output switching begins when Q1 is turned on by the gate drive transformer T1, charging the output filter capacitor C3 through L1. D5 supplies a regulated +12V to V circuit is running ...
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... COMP 4.3k FB 47k ISNS RT/CT 2200 pF 3.3k 10k *Locate near the MIC38C43 supply pins. MIC38C42/3/4/5 at 500kHz. CT1 and T1 are wound on Magnetics, Inc. P-type material toroids wound on a Siemens N49 EFD core. Results Symbol = 2A 0.5% CT1 0.6% T1 90% L1 100mV 1. Custom Coils, Alcester, SD tel: (605) 934-2460 2 ...
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... Plastic DIP (N) 9 0.255 (6.48) 0.245 (6.22) 0.300 (7.62) 0.013 (0.330) 0.010 (0.254) .310 (7.874) .280 (7.112) .015 (0.381) .008 (0.2032) .400 (10.180) .330 (8.362) MIC38C42/3/4/5 Micrel ...
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... MIC38C42/3/4/5 0.026 (0.65) 0.157 (3.99) 0.150 (3.81) 0.064 (1.63) 0.045 (1.14) 0.122 (3.10) 0.112 (2.84) 0.036 (0.90) 0.032 (0.81) 0.012 (0.03) 0.0256 (0.65) TYP 0.154 (3.90) 0.026 (0.65) MAX) 0.057 (1.45) 0.049 (1.25) MIC38C42/3/4/5 MAX) PIN 1 DIMENSIONS: INCHES (MM) 0.020 (0.51) 0.013 (0.33) 0.050 (1.27) TYP 0.0098 (0.249) 0.0040 (0.102) 0°–8° 0.197 (5.0) 0.189 (4.8) SEATING PLANE 8-Pin SOP (M) 0.199 (5.05) ...
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... MIC38C42/3/4/5 August 2000 11 Micrel MIC38C42/3/4/5 ...
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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. MIC38C42/3/4 (408) 944-0970 http://www ...