MAX8744AETJ+ Maxim Integrated Products, MAX8744AETJ+ Datasheet
MAX8744AETJ+
Specifications of MAX8744AETJ+
Related parts for MAX8744AETJ+
MAX8744AETJ+ Summary of contents
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... Input Range o 2V ±0.75% Reference Output o Independent Enable Inputs and Power-Good Outputs o Soft-Start and Soft-Shutdown (Voltage Ramp) o 8µA (typ) Shutdown Current PART MAX8744AETJ+ MAX8745AETJ+* -40°C to +85°C + Denotes a lead-free package. * Future product—contact factory for availability. TOP VIEW Applications PGOOD3 ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS IN, SHDN, DRVA, OUTA to GND............................-0.3V to +28V LDO5, ON3, ON5, ONA to GND ..............................-0.3V to +6V PGOODA, PGOOD3, PGOOD5 to GND...................-0.3V to +6V CSL3, CSH3, CSL5, CSH5 ...
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... Current-Limit Threshold (Fixed) Current-Limit Threshold (Adjustable) Current-Limit Threshold (Negative) Current-Limit Threshold (Zero Crossing) Idle Mode™ Threshold Idle Mode Threshold (Low Audible-Noise Mode) ILIM Leakage Current Idle Mode is a trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ = +25°C.) A CONDITIONS Either SMPS 2.1V FB3 FB5 Either SMPS, SKIP = LDO5, 0 < ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I (Circuit of Figure load ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I (Circuit of Figure load ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I (Circuit of Figure load ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I (Circuit of Figure load ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, both SMPS enabled, FSEL = REF, SKIP = GND, ILIM = LDO5, FBA = LDO5, I (Circuit of Figure load ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers = 12V, SKIP = GND, FSEL = REF, T (Circuit of Figure OUTPUT EFFICIENCY vs. LOAD CURRENT 100 7V 90 12V 80 70 20V 60 SKIP MODE ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers = 12V, SKIP = GND, FSEL = REF, T (Circuit of Figure 3.3V IDLE MODE CURRENT vs. INPUT VOLTAGE 3 SKIP MODE SKIP = GND 2 1 LOW-NOISE ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers = 12V, SKIP = GND, FSEL = REF, T (Circuit of Figure SOFT-START WAVEFORM MAX8744A toc16 3. 12V 400μs/div A. ON3 ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers = 12V, SKIP = GND, FSEL = REF, T (Circuit of Figure SKIP TRANSITION MAX8744A toc22 3.3V 0 3.35V 3.25V 2A 0 12V 0 40μs/div A. SKIP, 5V/div ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PIN NAME Auxiliary LDO Enable Input. When ONA is pulled low, OUTA is high impedance and the secondary 1 ONA feedback control is disabled. When ONA is driven high, the controller ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PIN NAME Boost Flying Capacitor Connection for the 5V SMPS. The MAX8744A/MAX8745A include an internal 15 BST5 boost switch connected between LDO5 and BST5. Connect to an external capacitor as shown ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PIN NAME Adjustable Auxiliary Linear-Regulator Output. Bypass OUTA to GND with 1µF or greater capacitor (1µF/25mA). When DRVA < OUTA, the secondary feedback control triggers the DL5 for 1µs forcing the ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers L3 3.3V PWM OUTPUT C OUT3 D R1 6.96kΩ R2 3.48kΩ C1 0.22μF C3 1000pF SECONDARY OUTPUT 12V LDO OUTPUT C LDOA 4.7μF ON Figure 1. Standard Application Circuit 16 ______________________________________________________________________________________ ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Table 2. Component Suppliers SUPPLIER AVX www.avx.com Central Semiconductor www.centralsemi.com Fairchild www.fairchildsemi.com International Rectifier www.irf.com KEMET www.kemet.com NEC/Tokin www.nec-tokin.com Panasonic www.panasonic.com/industrial Philips www.philips.com Pulse www.pulseeng.com Renesas www.renesas.com SANYO www.edc.sanyo.com Sumida www.sumida.com ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers making the threshold to exit shutdown less accurate. To guarantee startup, drive SHDN above 2V (SHDN input rising-edge trip level). For automatic shutdown and startup, connect SHDN The ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Table 3. Operating Mode Truth Table INPUTS* MODE SHDN ON5 Shutdown Mode Low Standby Mode High Low Normal Operation High High 3.3V SMPS Active High Low 5V SMPS Active High High ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers SKIP TRI-LEVEL DECODE 0 LIMIT A = 1/10 ILIM A = 1.2 CSH_ CSL_ DRVA OUTA Figure 3. PWM Controller Functional Diagram Fixed-Frequency, Current-Mode The heart of each current-mode ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Table 4. FSEL Configuration Table FSEL SWITCHING FREQUENCY (kHz) LDO5 REF GND Frequency Selection (FSEL) The FSEL input selects the PWM mode switching fre- quency. Table 4 shows the switching frequency ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers The switching waveforms may appear noisy and asyn- chronous when light loading causes pulse-skipping operation, but this is a normal operating condition that results in high light-load efficiency. Trade-offs in PFM ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers In forced-PWM mode, the MAX8744A/MAX8745A also implement a negative current limit to prevent excessive reverse inductor currents when V OUT The negative current-limit threshold is set to approxi- mately 120% of ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Table 5. Operating Modes Truth Table MODE Power-Up LDO5 < UVLO threshold SHDN = high, ON3 or ON5 enabled Run Output Overvoltage (OVP) Protection Either output > 111% of nominal level ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Auxiliary LDO Detailed Description The MAX8744A/MAX8745A include an auxiliary linear regulator (OUTA) that can be configured for 12V, ideal for PCMCIA power requirements, and for biasing the gates of load switches ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Ferrite cores are often the best choice, although pow- dered iron is inexpensive and can work well at 200kHz. The core must be large enough not to saturate at the peak ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers where I equals the minimum current-limit thresh- LIMIT_ old voltage divided by the current-sense resistance (R ). For the default setting, the minimum current- SENSE_ limit threshold is 45mV. Connect ILIM ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers current, allowing accurate current-limit protection. However, the parasitic inductance of the current-sense resistor can cause current-limit inaccuracies, especially when using low-value inductors and current-sense resistors. This parasitic inductance (L celed by ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Do not put high-value ceramic capacitors directly across the feedback sense point without taking precau- tions to ensure stability. Large ceramic capacitors can have a high ESR zero frequency and cause ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers The 40/60 optimal interleaved architecture of the MAX8744A/MAX8745A allows the input voltage low 8.3V before the duty cycles begin to overlap. This offers improved efficiency over a regular ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ⎛ Δ I INDUCTOR = − ⎜ LOAD LIMIT ⎝ where I is the peak current allowed by the current- LIMIT limit circuit, including threshold tolerance and sense- resistance ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers The output capacitor and the load resistance create the dominant pole in the system. However, the internal ampli- fier delay, the pass transistor’s input capacitance, and the stray capacitance at the ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers ⎛ ⎜ IN MIN ( ) OUT CHG ⎝ D MAX where V and V are the parasitic voltage drops in CHG DIS ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers SINGLE n-CHANNEL MOSFETS INDUCTOR C IN INPUT GROUND HIGH-POWER LAYOUT Figure 9. PCB Layout Chip Information TRANSISTOR COUNT: 6897 PROCESS: BiCMOS 34 ______________________________________________________________________________________ MAX8744A/MAX8745A CONNECT THE EXPOSED PAD TO ANALOG GND ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information 35 ...
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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. 36 Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products Package Information (continued) ...