MAX1864TEEE+T Maxim Integrated Products, MAX1864TEEE+T Datasheet
MAX1864TEEE+T
Specifications of MAX1864TEEE+T
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MAX1864TEEE+T Summary of contents
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... Cable, and ISDN Modems Set-Top Boxes Wireless Local Loop ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ 4.5V to 28V Input Voltage Range ♦ ...
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... VALLEY (Internal Mode) Current-Limit Threshold V VALLEY (External Mode) Dual Mode is a trademark of Maxim Integrated Products, Inc. 2 _______________________________________________________________________________________ Continuous Power Dissipation (T 16-Pin QSOP (derate 8.3mW/°C above +70°C)...........666mW 20-Pin QSOP (derate 9.1mW/°C above +70°C)...........727mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150° ...
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Modem Triple/Quintuple Output ELECTRICAL CHARACTERISTICS (continued 12V, ILIM = FB = GND BST PARAMETER SYMBOL Switching Frequency Maximum Duty Cycle Soft-Start Period Soft-Start Steps DH Output Low Voltage DH Output High Voltage DL ...
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Modem Triple/Quintuple Output Power Supplies ELECTRICAL CHARACTERISTICS (V = 12V, ILIM = FB = GND BST LX PARAMETER SYMBOL GENERAL Operating Input Voltage Range V (Note 1) Quiescent Supply Current I VL REGULATOR Output Voltage ...
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Modem Triple/Quintuple Output ELECTRICAL CHARACTERISTICS (continued 12V, ILIM = FB = GND BST PARAMETER SYMBOL POWER GOOD (POK) OUT Trip Level (Preset Mode) FB Trip Level (Adjustable Mode) FB2, FB3, FB4 Trip Level ...
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Modem Triple/Quintuple Output Power Supplies (Circuit of Figure 12V 3.3V OUT OUPUT VOLTAGE vs. LOAD CURRENT (ADJUSTABLE MODE) 5.05 5.03 5.01 4.99 4.97 4.95 0 0.5 1.0 1.5 2.0 2.5 3.0 LOAD ...
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Modem Triple/Quintuple Output (Circuit of Figure 12V 3.3V OUT POSITIVE LINEAR REGULATOR OUTPUT VOLTAGE vs. LOAD CURRENT (Q = 2N3905) LDO 2.50 2. 5.0V SUP(POS) 2. 3.3V SUP(POS) ...
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Modem Triple/Quintuple Output Power Supplies (Circuit of Figure 12V 3.3V OUT POSITIVE LINEAR REGULATOR POWER-SUPPLY REJECTION RATIO (Q = TIP30) LDO 150mA 10 ...
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Modem Triple/Quintuple Output PIN NAME MAX1864 MAX1865 1 1 POK 2 2 COMP 3 3 OUT FB2 FB3 — — 10 FB4 — 11 ...
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Modem Triple/Quintuple Output Power Supplies PIN NAME MAX1864 MAX1865 9 13 ILIM 10 14 GND BST Detailed Description The MAX1864/MAX1865 power-supply controllers ...
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Modem Triple/Quintuple Output IN C1 1μ 1μF ILIM R POK 100kΩ POK FB R COMP 47kΩ COMP C COMP 8.2nF Figure 1. Standard MAX1864 Application Circuit the voltage across the load. Under overload conditions, when the inductor ...
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Modem Triple/Quintuple Output Power Supplies MAX1864 MAX1865 COMP OUT FB 100mV FB_ B_ 0.9V REF FB1 0.9V REF OUT B5* FB5* *MAX1865 ONLY Figure 2. Functional Diagram 12 ______________________________________________________________________________________ ENABLE FB1 ∑ SOFT- START ...
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Modem Triple/Quintuple Output Current-Limit Circuit The current-limit circuit employs a unique “valley” cur- rent-limiting algorithm that uses the low-side MOSFET’s on-resistance as a sensing element (Figure 3). If the voltage across the low-side MOSFET (R ) exceeds the current-limit ...
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Modem Triple/Quintuple Output Power Supplies Undervoltage Lockout If VL drops below 3.5V, the MAX1864/MAX1865 assume that the supply voltage is too low to make valid decisions, so the undervoltage lockout (UVLO) circuitry inhibits switching, forces POK low, and forces ...
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Modem Triple/Quintuple Output FOR OUTPUT VOLTAGES > 5V, SEE "OUTPUT VOLTAGE SELECTION." Figure 4. Adjustable Output Voltage where f is 200kHz for MAX186_T and 100kHz for SW MAX186_U. The exact inductor value is not critical and ...
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Modem Triple/Quintuple Output Power Supplies The MAX1864/MAX1865s’ step-down controller drives two external logic-level N-channel MOSFETs as the cir- cuit switch elements. The key selection parameters are: • On-resistance (R ) DS(ON) • Maximum drain-to-source voltage (V • Minimum threshold ...
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Modem Triple/Quintuple Output MAX1864 BST MAX1865 R GATE (OPTIONAL BST GATE (OPTIONAL) DH GND Figure 5. Reducing the Switching EMI The key selection parameters for the output capacitor are the actual capacitance value, ...
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Modem Triple/Quintuple Output Power Supplies OUT REF VEA = I PEAK V R OUT NOMINAL where A is the current-sense amplifier’s gain (4.9 VCS typ the DC gain of the ...
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Modem Triple/Quintuple Output C1 1μF C2 1μF R POK 100kΩ TO LOGIC R COMP 47kΩ C COMP 8.2nF C15 10nF R10 470Ω BE5 BE5 2200pF 220Ω Q4 TIP29 C12 10μF V OUT5 -12V AT 50mA C11 D4 ...
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Modem Triple/Quintuple Output Power Supplies Transistor Selection The pass transistors must meet specifications for cur- rent gain (h ), input capacitance, collector-emitter sat- FE uration voltage, and power dissipation. The transistor’s current gain limits the guaranteed maximum output cur- ...
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Modem Triple/Quintuple Output ƒ ≈ POLE 2π C OUT ESR Do not use output capacitors with more than 200mΩ of ESR. Typically, more output capacitance provides the best solution, since this also reduces the output voltage ...
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Modem Triple/Quintuple Output Power Supplies only), connect the transformer as shown in Figure 6, where the minimum turns ratio is determined by: ⎛ LDO NEG ( ) SAT ≥ ⎜ ⎜ N NEG V ...
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Modem Triple/Quintuple Output 5) Ensure all feedback connections are short and direct. Place the feedback resistors as close to the MAX1864/MAX1865 as possible. 6) When trade-offs in trace lengths must be made, it’s preferable to allow the inductor charging ...
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Modem Triple/Quintuple Output Power Supplies MAX1864 MAX1865 a) POSITIVE OUTPUT VOLTAGE WITH CASCODED BASE DRIVE MAX1865 b) NEGATIVE OUTPUT VOLTAGE (MAX1865 ONLY) WITH CASCODED BASE DRIVE Figure 8. High-Voltage Linear Regulation Table 1. Component Suppliers SUPPLIER INDUCTORS AND TRANSFORMERS ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 25 © 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...