MAX1585ETJ+ Maxim Integrated Products, MAX1585ETJ+ Datasheet

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... ONSU ONSD AUX2 ON1 AUX3 ON2 ON3 ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. ♦ Step-Up DC-DC Converter, 95% Efficient ♦ Step-Down DC-DC Converter Operate from Battery for 95% Efficient Step-Down 90% Efficient Boost-Buck with Step-Up ♦ ...

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Slim DSC Power Supplies ABSOLUTE MAXIMUM RATINGS SDOK, AUX1OK, SCF, ON_, FB_ to PV, PVSU, PVSD, GND..........................................................................-0.3V to +6V PGND to GND....................................................…-0.3V to +0.3V INDL2, DL1, DL3 to GND.........................-0.3V to (PVSU + 0.3V) DL2 to GND ............................................-0.3V to (INDL2 ...

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... Switch On-Resistance P channel P-Channel Current Limit N-Channel Turn-Off Current Soft-Start Interval SDOK Output Low Voltage 0.1mA into SDOK SDOK Leakage Current ONSU = GND Idle Mode is a trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ = 0°C to +85°C, unless otherwise noted.) A CONDITIONS = 0V, PVSU = 5. 5.5V OUT = ...

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Slim DSC Power Supplies ELECTRICAL CHARACTERISTICS (continued 3.6V, T PVSU PV PVSD INDL2 PARAMETER AUX1 DC-DC CONTROLLERS Maximum Duty Cycle FB_ = 1V FB1 and FB3 Regulation Voltage FB_ ...

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Slim DSC Power Supplies ELECTRICAL CHARACTERISTICS ( 3.6V, T PVSU PV PVSD INDL2 PARAMETER GENERAL Input Voltage Range (Note 2) Shutdown Supply Current PVSU = 3.6V into PVSU Supply Current into PV ...

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Slim DSC Power Supplies ELECTRICAL CHARACTERISTICS (continued 3.6V, T PVSU PV PVSD INDL2 PARAMETER FBSD Regulation Voltage FBSD to CCSD FBSD = CCSD Transconductance FBSD Input Leakage Current FBSD = 1.25V ...

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Slim DSC Power Supplies ELECTRICAL CHARACTERISTICS (continued 3.6V, T PVSU PV PVSD INDL2 Note 5: The step-up current limit in startup refers to the LXSU switch current limit, not an output ...

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Slim DSC Power Supplies (Circuit of Figure +25°C, unless otherwise noted.) A NO-LOAD INPUT CURRENT vs. INPUT VOLTAGE (SWITCHING BOOST-BUCK (SU + AUX3 5.0V, OUT3 = 3.33V ...

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Slim DSC Power Supplies (Circuit of Figure +25°C, unless otherwise noted.) A AUX MAXIMUM DUTY CYCLE vs. FREQUENCY 88 WHEN THIS DUTY CYCLE IS EXCEEDED 87 FOR 100,000 CLOCK CYCLES, THE MAX1584/MAX1585 SHUT DOWN 86 85 ...

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Slim DSC Power Supplies PIN NAME AUX1 Controller Compensation Node. Connect a series resistor-capacitor from CC1 to GND to 1 CC1 compensate the converter control loop. This pin is actively driven to GND in shutdown, overload, and thermal limit. ...

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Slim DSC Power Supplies PIN NAME Open-Drain Power-OK Signal for AUX1 Controller. AUX1OK is low when the AUX1 controller has AUX1OK 16 successfully completed soft-start. This pin is high impedance in shutdown, overload, and thermal limit. Open-Drain Power-OK Signal ...

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Slim DSC Power Supplies PIN NAME AUX3 Step-Down Controller Gate-Drive Output. Connect to the gate of a P-channel MOSFET. DL3 swings 28 DL3 from GND to PVSU and supplies up to 500mA. DL3 is driven to PVSU in shutdown ...

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Slim DSC Power Supplies V IN 1.5V TO 4.2V C24 10μF D2 -7.5V -CDD C8 BIAS 4.7μF R8 526kΩ R9 93.1kΩ TO PVSU R1 R2 47kΩ R3 25kΩ R5 20kΩ C1 10kΩ 61.9kΩ 0.01μF C2 470pF 4700pF C3 1500pF ...

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Slim DSC Power Supplies PVSU 2.35V ONSU V REF 1V ONSU OSC CCSU FBSU STEP-UP SOFT-START DONE (SUSSD) CCSD FBSD RAMP GENERATOR ONSD SUSSD Figure 2. MAX1584/MAX1585 Functional Diagram 14 ______________________________________________________________________________________ INTERNAL NORMAL POWER-OK MODE OVER REFOK TEMP FAULT ...

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Slim DSC Power Supplies Step-Down DC-DC Converter The step-down DC-DC converter is optimized for gen- erating low output voltages (down to 1.25V) at high effi- ciency. Output voltages lower than 1V can be set by adding an additional resistor ...

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Slim DSC Power Supplies FB_ MAX1584 AUX1 AND AUX2, MAX1585 AUX1 STEP-UP CONTROLLER CC_ LEVEL SHIFT REFI SOFT-START REF (REFI RAMPS FROM 0V TO REF IN 1024 OSC 0.85 CYCLES) REF CLK OSC PROTECTION Figure 3. AUX Controller Functional ...

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Slim DSC Power Supplies to drive an N-channel MOSFET. Its feedback (FB1) threshold is 1.25V. In the MAX1584, AUX2 is identical to AUX1. In the MAX1585, AUX2 is an inverting controller that generates a regulated negative output voltage, typically ...

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Slim DSC Power Supplies OSC OSC C V OSC REF (1.25V) 150ns ONE-SHOT MAX1584 MAX1585 Figure 4. Oscillator Functional Diagram end of the soft-start interval. If PVSU is dragged below the input, the overload is supplied ...

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Slim DSC Power Supplies iary converters and cannot be activated until PVSU is in regulation. For automatic startup, connect ON_ to PVSU or a logic level greater than 1.6V. Design Procedure Setting the Switching Frequency Choose a switching frequency ...

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Slim DSC Power Supplies IND(PK) OUT Inductance values smaller than L IDEAL reduce inductor size; however, if much smaller values are used, inductor current rises and a larger output capaci- tance might be required ...

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Slim DSC Power Supplies If Z > can be ignored typically the case ESR C with ceramic output capacitors should be cancelled with a pole set by capacitor C connected from ...

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Slim DSC Power Supplies Significant MOSFET selection parameters are as fol- lows: • On-resistance (R ) DS(ON) • Maximum drain-to-source voltage (V • Total gate charge ( • Reverse transfer capacitance (C DL1 and DL3 swing between ...

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Slim DSC Power Supplies not less than (as is typical with COUT RHP ceramic output capacitors) and continuous conduction is required, then cross the loop over before Z f < 10, ...

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Slim DSC Power Supplies MAX1585 AUX2 Inverter Compensation, Discontinuous Inductor Current If the load current is very low (40mA or less), discontin- uous current is preferred for simple loop compensation and freedom from duty-cycle restrictions on the inverter input-output ...

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Slim DSC Power Supplies TO V BATT 1μF DL_ 1μF WHITE LEDS FB_ 62Ω (FOR 20mA) NOTE: THIS CIRCUIT CAN OPERATE WITH AUX1 OR AUX2 ON THE MAX1584, AND WITH AUX1 ON THE MAX1585. Figure 6. AUX_ Channel Powering ...

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Slim DSC Power Supplies MAX1585 TO V BATT (PARTIAL) INDL2 DL2 AUX2 INVERTING FB2 PWM REF Figure 8. Regulated -7.5V Negative CCD Bias Provided by Conventional Inverter (MAX1585 Only) L1 10μ BATT C2 1μF 1μF FB_ ...

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Slim DSC Power Supplies TO BATT V OUT DL IN OSC MAX1801 FB COMP REF GND DCON Figure 12. Adding a PWM Channel with an External MAX1801 Slave Controller MAX1584/MAX1585 (PARTIAL) AUX3 V-MODE DL3 STEP-DOWN PWM FB3 ON3 SDOK ...

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Slim DSC Power Supplies MAX1584 MAX1585 PV (PARTIAL) PVSU TO V BATT L2 CURRENT-MODE LXSU STEP-UP PWM PGSU FBSD SCF OK PWR-ON OR FAULT Figure 15. SCF controls a PFET load switch to disconnect all 5V loads on fault. ...

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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 ____________________ 29 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...