MC34166 ON Semiconductor, MC34166 Datasheet
MC34166
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MC34166 Summary of contents
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... MC34166, MC33166 3.0 A, Step−Up/Down/ Inverting Switching Regulators The MC34166, MC33166 series are high performance fixed frequency power switching regulators that contain the primary functions required for dc−to−dc converters. This series was specifically designed to be incorporated in step−down and voltage−inverting configurations with a minimum number of external components and can also be used cost effectively in step− ...
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... TO−220 − Horizontal Mount TO−220 − Horizontal Mount (Pb−Free) TO−220 − Vertical Mount TO−220 − Vertical Mount (Pb−Free) MC34166 MC33166 = + 70°C for MC34166 = + 85°C for MC33166 http://onsemi.com 2 † Shipping 50 Units/Rail 800 / Tape & Reel 50 Units/Rail 800 / Tape & Reel ...
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... OL DC (max) DC (min Source sat I sw(off) I pk(switch) = +25° th(UVLO) V H(UVLO 70°C for MC34166 high = + 85°C for MC33166 http://onsemi.com 3 is the operating ambient A Min Typ Max Unit kHz 62 − 81 4.95 5.05 5.15 V 4.85 − 5.2 − 0.03 0.078 ...
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... Figure 4. Error Amp Open Loop Gain and Phase versus Frequency 4.0 0 − 4.0 − 8.0 − 12 − 55 − AMBIENT TEMPERATURE (°C) A Figure 6. Oscillator Frequency Change versus Temperature MC34166, MC33166 100 Max = 5. Typ = 5. Min = 4. 100 125 − 55 − 25 Figure 3. Voltage Feedback Input Bias 2.0 ...
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... V Increasing CC 5.5 Turn−Off Threshold V Decreasing 5.0 CC 4.5 4.0 − 55 − AMBIENT TEMPERATURE (°C) A Figure 12. Undervoltage Lockout Threshold versus Temperature MC34166, MC33166 − 0.2 CC Pin +25°C A Pins GND − 0.4 Pin 2 Driven Negative − 0.6 − 0.8 −1.0 −1.2 4.0 5.0 − 55 − 25 Figure 9. Negative Switch Output Voltage ...
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... MC34166, MC33166 + Oscillator C T Pulse Width PWM Latch Modulator Thermal Shutdown GND Compensation 3 Figure 14. MC34166 Representative Block Diagram 4.1 V Timing Capacitor C T Compensation 2 Switch Output OFF Figure 15. Timing Diagram V in Current 4 Sense Input Voltage/V S Switch Q Output R 2 Undervoltage Lockout 5.05 V Reference + Voltage ...
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... The MC34166, MC33166 series are monolithic power switching regulators that are optimized for dc−to−dc converter applications. These devices operate as fixed frequency, voltage mode regulators containing all the active functions required to directly implement step−down and voltage−inverting converters with a minimum number of external components. They can also be used cost effectively in step− ...
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... This feature is provided to prevent catastrophic failures from accidental device overheating not intended to be used as a substitute for proper heatsinking. The MC34166 is contained in a 5−lead TO−220 type package. The tab of the package is common with the center pin (Pin 3) and is normally connected to ground. ...
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... V by controlling the percent conduction time ref voltage greater than 5.05 V, resistor R must be added to form a divider network at the feedback input. 1 3.0″ (Bottom View) Figure 20. Step−Down Converter Printed Circuit Board and Component Layout MC34166, MC33166 4 ILIMIT UVLO ...
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... Magnetics Inc. 58350−A2 core. Heatsink = AAVID Engineering Inc. Figure 21 shows that the MC34166 can be configured as a step−up/down converter with the addition of an external power MOSFET. Energy is stored in the inductor during the on−time of transistors Q the output filter capacitor and load. This circuit configuration has two significant advantages over the basic step−up converter circuit. The first advantage is that output short− ...
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... Magnetics Inc. 58350−A2 core. Heatsink = AAVID Engineering Inc. 5903B, or 5930B. Two potential problems arise when designing the standard voltage−inverting converter with the MC34166. First, the Switch Output emitter is limited to −1.5 V with respect to the ground pin and second, the Error Amplifier’s noninverting input is internally committed to the reference and is not pinned out. Both of these problems are resolved by connecting the IC ground pin to the converter’ ...
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... Note that the 12 V winding is stacked on top of the 5.0 V output. This reduces the number of secondary turns and improves lead regulation. For best auxiliary regulation, the auxiliary outputs should be less than 33% of the total output power. MC34166, MC33166 4 ILIMIT ...
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... MC34166, MC33166 + Oscillator S R PWM Thermal −12 V 1000 + *Gate resistor R , zener diode D G Test Line Regulation V = − − Load Regulation V = − Output Ripple V = − Efficiency V = − Coilcraft M1496−A or ELMACO CHK1050, 42 turns of #16 AWG on Magnetics Inc. ...
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... Total Gap − 0.002″ 1 The MC34166 can be used cost effectively in off−line applications even though it is limited to a maximum input voltage Figure 28 shows a simple and efficient method for converting the AC line voltage down This preconverter has a total power rating of 125 W with a conversion efficiency of 90% ...
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... Desired peak−to−peak output ripple voltage. For best performance, the ripple voltage should be kept to less than ripple(pp) Capacitor C should be a low equivalent series resistance (ESR) electrolytic designed for switching regulator applications. O MC34166, MC33166 Table 1. Design Equations Step−Up/Down V out ) satQ1 * V satQ2 ...
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... Q CHAMFER 0.24 (0.610 0.10 (0.254 MC34166, MC33166 PACKAGE DIMENSIONS TO−220 TH SUFFIX CASE 314A−03 ISSUE E NOTES: SEATING −T− 1. DIMENSIONING AND TOLERANCING PER ANSI PLANE Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH DIMENSION D DOES NOT INCLUDE INTERCONNECT BAR (DAMBAR) PROTRUSION. ...
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... DETAIL A− 0.356 (0.014 MC34166, MC33166 TO−220 T SUFFIX CASE 314D−04 ISSUE F SEATING NOTES: −T− PLANE 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982 CONTROLLING DIMENSION: INCH DIMENSION D DOES NOT INCLUDE INTERCONNECT BAR (DAMBAR) PROTRUSION ...
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... Literature Distribution Center for ON Semiconductor P.O. Box 61312, Phoenix, Arizona 85082−1312 USA Phone: 480−829−7710 or 800−344−3860 Toll Free USA/Canada Fax: 480−829−7709 or 800−344−3867 Toll Free USA/Canada Email: orderlit@onsemi.com MC34166, MC33166 PACKAGE DIMENSIONS 2 D PAK D2T SUFFIX CASE 936A− ...