MAX8744ETJ+ Maxim Integrated Products, MAX8744ETJ+ Datasheet
MAX8744ETJ+
Specifications of MAX8744ETJ+
Related parts for MAX8744ETJ+
MAX8744ETJ+ Summary of contents
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... Undervoltage and Thermal-Fault Protection o Overvoltage-Fault Protection (MAX8744 Only 26V 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 MAX8744ETJ+ MAX8745ETJ+ + Denotes lead-free package. TOP VIEW BST3 PGOOD3 Applications CSL3 CSH3 ...
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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 MAX8744 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 MAX8744 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 MAX8744/MAX8745 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 Auxiliary LDO Feedback Input. Connect a resistive voltage-divider from OUTA to analog ground to 31 FBA adjust the auxiliary linear-regulator output voltage. FBA regulates at 1V. Adjustable Auxiliary Linear-Regulator ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers L1 3.3V PWM OUTPUT C OUT1 R1 5.62kΩ R2 3.92kΩ C1 0.22μF C3 1000pF SECONDARY OUTPUT 12V LDO OUTPUT C LDOA 4.7μF Figure 1. Standard Application Circuit 16 ______________________________________________________________________________________ C IN ...
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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 OSC FSEL ILIM SKIP CSH3 CSL3 LDO5 BST3 DH3 LX3 LDO5 DL3 PGND FB3 ON3 PGOOD5 PGOOD3 PGOODA Figure 2. Functional Diagram 18 ______________________________________________________________________________________ CONTROLLER PWM3 CONTROLLER (FIGURE 3) FB DECODE ...
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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 within 4ms after the SMPS controllers are ...
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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 Fixed-Frequency, Current-Mode The heart of each current-mode PWM controller is a multi-input, open-loop comparator that sums two sig- nals: ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers a broader efficiency vs. load curve, while higher values result in higher full-load efficiency (assuming that the coil resistance remains fixed) and less output-voltage ripple. Penalties for using higher inductor values ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers When adjusting both output voltages, set the 3.3V SMPS lower than the 5V SMPS. LDO5 connects to the 5V output (CSL5) through an internal switch only when CSL5 is above the ...
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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 ON3, ON5, or SHDN to clear the fault latch and restart the SMPS controllers. Output Undervoltage Protection (UVP) Each SMPS controller includes an output UVP protec- tion circuit that begins to ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Inductor Selection The switching frequency and inductor operating point determine the inductor value as follows: ( − OUT IN OUT = OSC LOAD ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers MAX8744 MAX8745 N DH_ LX_ N DL_ PGND CSH_ CSL_ A) OUTPUT SERIES RESISTOR SENSING MAX8744 MAX8745 N DH_ LX_ N DL_ PGND CSH_ CSL_ B) LOSSLESS INDUCTOR SENSING Figure 7. ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers current to slew faster, replenishing charge removed from the output filter capacitors by a sudden load step. The total output voltage sag is the sum of the voltage sag while the ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (see the Output-Capacitor Stability Consideration section), the filter capacitor’s ESR dominates the output voltage rip- ple. So the output capacitor’s size depends on the maxi- mum ESR required to meet the ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers INPUT RMS CURRENT FOR INTERLEAVED OPERATION − − RMS OUT OUT 5 OUT 3 = ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers Choose a low-side MOSFET (N ) that has the lowest pos- L sible on-resistance (R ), comes in a moderate-sized DS(ON) package (i.e., 8-pin SO, DPAK ably priced. Ensure ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers (V = 5V). Using the above equation, the required GS boost capacitance would be 065 . BST 200 mV Selecting the closest standard value, this ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers 3) Next, calculate the pole set by the transistor’s input capacitance, the transistor’s input resistance, and the base-to-emitter pullup resistor. Since the transistor’s input resistance ( typically much ...
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High-Efficiency, Quad-Output, Main Power- Supply Controllers for Notebook Computers PCB Layout Guidelines Careful PCB layout is critical to achieving low switching losses and clean, stable operation. The switching power stage requires particular attention (Figure 9). If possible, mount all the ...
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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 ______________________________________________________________________________________ MAX8744/MAX8745 CONNECT THE EXPOSED PAD TO ANALOG GND CONNECT ...
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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 © 2006 Maxim Integrated Products Package Information ...