MAX8756ETI+T Maxim Integrated Products, MAX8756ETI+T Datasheet
MAX8756ETI+T
Specifications of MAX8756ETI+T
Related parts for MAX8756ETI+T
MAX8756ETI+T Summary of contents
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... The MAX8716 is available in a 24-pin thin QFN pack- age, and the MAX8717/MAX8756/MAX8757 are avail- able in a 28-pin thin QFN package Li+ Cell Battery-Powered Devices Notebook and Subnotebook Computers PDAs and Mobile Communicators Main or I/O Power Supplies Dual Mode is a trademark of Maxim Integrated Products, Inc. TOP VIEW 18 17 DH1 19 BST1 ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS (Note CSL1, CSH1, CSL2, CSH2 to AGND ......-0. ON1, ON2, SKIP1, SKIP2, PGOOD1, PGOOD2 to AGND ...............................................-0.3V to +6V FB1, ...
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... Current-Limit Threshold (Fixed) V Current-Limit Threshold V (Adjustable) Current-Limit Threshold V (Negative) Current-Limit Threshold (Zero Crossing) Idle Mode™ Threshold V Idle Mode is a trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ = ON_ ILIM_ CC CONDITIONS Dual Mode comparator FB1 = 1.1V, FB2 = 1.1V Either SMPS, SKIP_ = V , zero to full load CC Either SMPS, 4V < ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, FSEL = REF, SKIP_ = 0, V (Circuit of Figure Typical values are +25°C.) A PARAMETER SYMBOL Low-Noise-Mode Threshold ILIM_ Leakage ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, FSEL = REF, SKIP_ = 0, V (Circuit of Figure Typical values are +25°C.) A PARAMETER SYMBOL INPUTS AND OUTPUTS Logic ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) = 12V, FSEL = REF, SKIP_ = 0, V (Circuit of Figure noted.) (Note 6) PARAMETER SYMBOL Operating Frequency Maximum Duty Factor D Minimum On-Time t ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers (Circuit of Figure 1, MAX8717 12V 3.3V OUTPUT EFFICIENCY vs. LOAD CURRENT 100 SKIP MODE 90 80 LOW- PWM NOISE MODE MODE ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers (Circuit of Figure 1, MAX8717 12V 1.8V OUTPUT EFFICIENCY vs. LOAD CURRENT 100 V = 12V 3.2μH 90 SKIP MODE 80 70 PWM MODE LOW-NOISE ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers (Circuit of Figure 1, MAX8717 12V STARTUP WAVEFORMS MAX8716/17/57 toc18 A 12V 400μs/div A. LX2, 20V/div ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers (Circuit of Figure 1, MAX8717 12V OUT1 LOAD TRANSIENT MAX8716/17/57 toc24 12V D 0 20μs/div A. CONTROL, 5V/div ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers PIN MAX8717/ NAME MAX8716 MAX8756/ MAX8757 REF FSEL — ON1 6 7 ON2 — 8 ILIM2 7 9 PGOOD2 ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers PIN MAX8717/ NAME MAX8716 MAX8756/ MAX8757 14 16 DL2 — GND — 18 PGND — 19 AGND 17 20 DL1 18 21 LX1 19 22 DH1 20 ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers +5V BIAS C1 1μF D BST1 BST1 0.1μ 5.7μ CS1 7mΩ 3.3V PWM OUTPUT C (1.5V FOR MAX8756) OUT1 220μ PULSE- ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers Table 1. Component Selection for Standard Applications MAX8716/MAX8717/MAX8757 COMPONENT 5V/5A, 3.3V/5A, 300kHz Input Voltage V IN (2) 10µF, 25V C , Input Capacitor IN Taiyo Yuden TMK432BJ106KM 220µF, 4V, 25mΩ ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers MAX8717/MAX8756/MAX8757 OSC FSEL SKIP1 ON1 ILIM1 CSH1 CSL1 BST1 DH1 LX1 V DD DL1 PGND DECODE FB1 (FIGURE 5) PGOOD1 Figure 2. Functional Diagram SMPS Enable Controls (ON1, ON2) ON1 and ON2 ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers Fixed-Frequency, Current-Mode PWM Controller The heart of each current-mode PWM controller is a multi-input, open-loop comparator that sums two sig- nals: the output-voltage error signal with respect to the reference voltage and ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers the switching frequency remains constant and the no-load supply current is typically between 8mA and 20mA per phase, depending on external MOSFETs and switching frequency. Light-Load Operation Control ( SKIP_ ) The ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers DC output accuracy specifications in the Electrical Characteristics refer to the error comparator’s thresh- old. When the inductor continuously conducts, the MAX8716/MAX8717/MAX8756/MAX8757 regulate the peak of the output ripple, so the actual ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers TO ERROR AMPLIFIER ADJUSTABLE OUTPUT FB 2V FIXED OUTPUT CSL Figure 5. Dual Mode Feedback Decoder Adjustable/Fixed Output Voltages (Dual-Mode Feedback) Connect FB1 and FB2 enable ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers The internal pulldown transistor that drives DL_ low is robust, with a 0.6Ω (typ) on-resistance. This helps pre- vent DL_ from being pulled up due to capacitive cou- pling from the drain ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers Output Undervoltage Protection If the output voltage of either SMPS falls below 70% of its regulation voltage, the corresponding controller sets its undervoltage fault latch, pulls PGOOD_ low, and begins soft-shutdown for ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers look for nonstandard values, which can provide a better compromise in LIR across the input voltage range. If using a swinging inductor (where the no-load induc- tance decreases linearly with increasing current), ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers MAX8716 MAX8717 MAX8756 MAX8757 a) OUTPUT SERIES RESISTOR SENSING MAX8716 MAX8717 MAX8756 MAX8757 b) LOSSLESS INDUCTOR SENSING Figure 8. Current-Sense Configurations Output Capacitor Selection The output filter capacitor must have low enough ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers Output-Capacitor Stability Considerations Stability is determined by the value of the ESR zero rel- ative to the switching frequency. The boundary of insta- bility is given by the following equation: ƒ SW ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers shows the input-capacitor RMS current vs. input volt- age for an application that requires 5V/5A and 3.3V/5A. This shows the improvement of the 40/60 optimal inter- leaving over 50/50 interleaving and in-phase ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers Choose a Schottky diode (D ) with a forward-voltage L drop low enough to prevent the low-side MOSFET’s body diode from turning on during the dead time general rule, select ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers • Minimize current-sensing errors by connecting CSH_ and CSL_ directly across the current-sense resistor (R ). SENSE_ • When trade-offs in trace lengths must be made preferable to allow the ...
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Interleaved High-Efficiency, Dual Power-Supply Controllers for Notebook Computers VIA TO POWER GROUND CONNECT THE EXPOSED PAD TO ANALOG GND VIA TO REF BYPASS CAPACITOR MAX8717/MAX8756/MAX8757 TOP LAYER SINGLE INDUCTOR n-CHANNEL MOSFETS INPUT HIGH-POWER LAYOUT Figure 10. PCB Layout Example Ordering ...
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Interleaved High-Efficiency, Dual 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 www.maxim-ic.com/packages.) ______________________________________________________________________________________ Package Information PACKAGE OUTLINE, 12, 16, 20, 24, ...
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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. 30 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products Package Information (continued registered trademark of Maxim Integrated Products, Inc ...