MAX1631AEAI+T Maxim Integrated Products, MAX1631AEAI+T Datasheet
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MAX1631AEAI+T
Specifications of MAX1631AEAI+T
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MAX1631AEAI+T Summary of contents
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... Pin Configurations and Selector Guide appear at end of data sheet. Idle Mode and Dual Mode are trademarks of Maxim Integrated Products. ________________________________________________________________ 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. ____________________________Features ♦ 96% Efficiency ♦ ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ABSOLUTE MAXIMUM RATINGS V+ to GND ..............................................................-0.3V to +36V PGND to GND.....................................................................±0. GND ................................................................-0.3V to +6V BST3, BST5 to GND ...............................................-0.3V to +36V LX3 to BST3..............................................................-6V to +0.3V LX5 to BST5..............................................................-6V ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = VL, VL load = 0mA, REF load = 0mA, SKIP = 0V, T Typical values are +25°C.) A PARAMETER ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ELECTRICAL CHARACTERISTICS (continued) (V+ = 15V, both PWMs on, SYNC = VL, VL load = 0mA, REF load = 0mA, SKIP = 0V, T Typical values are +25°C.) A PARAMETER ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers __________________________________________Typical Operating Characteristics (Circuit of Figure 1, 3A Table 1 components, T EFFICIENCY vs. 5V OUTPUT CURRENT 100 15V 80 70 ON5 = 5V ON3 = 0V ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ____________________________________Typical Operating Characteristics (continued) (Circuit of Figure 1, 3A Table 1 components, T SWITCHING FREQUENCY vs. LOAD CURRENT 1000 100 +5V 15V IN 10 +3.3V 15V IN 1 +3.3V, ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _________________________________________________Pin Description (continued) PIN NAME V DD Supply Voltage Input for the 12OUT Linear Regulator. Also connects to an internal resistor divider for (MAX1630/ secondary winding feedback, and to an 18V overvoltage shunt ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT C3 Q1 0.1μF R1 +5V OUTPUT ON/OFF 3.3V ON/OFF Figure 1. Standard 3.3V/5V Application Circuit (MAX1631/MAX1634) _______Standard Application Circuit The basic MAX1631/MAX1634 dual-output 3.3V/5V buck converter (Figure ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Table 1. Component Selection for Standard 3.3V/5V Application COMPONENT Input Range 4.75V to 18V Application PDA Frequency 300kHz 1/2 IR IRF7301; Q1, Q3 High-Side 1/2 Siliconix Si9925DQ; or MOSFETs 1/2 Motorola MMDF3N03HD or ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers INPUT +5V ALWAYS ON VL REF BST3 DH3 LX3 +3.3V DL3 CSH3 CSL3 R1 FB3 R2 0.6V TIME/ON5 Figure 2. MAX1632 Block Diagram 10 ______________________________________________________________________________________ SHDN V+ SYNC CSL5 - + 4.5V ON/OFF ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _______________Detailed Description The MAX1630 is a dual, BiCMOS, switch-mode power- supply controller designed primarily for buck-topology regulators in battery-powered applications where high effi- ciency and low quiescent supply current are critical. Light- load ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers REF MAIN PWM COMPARATOR SLOPE COMP 30mV SKIP DAC COUNTER SHDN SOFT-START -100mV REF SECFB Figure 3. PWM Controller Detailed Block Diagram 12 ______________________________________________________________________________________ 1X CURRENT LIMIT CK SYNCHRONOUS RECTIFIER CONTROL R Q ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers In PWM mode, the controller operates as a fixed- frequency current-mode controller where the duty ratio is set by the input/output voltage ratio. The current- mode feedback system regulates the peak inductor current ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers under all operating conditions, including Idle Mode. The SECFB signal further controls the synchronous switch timing in order to improve multiple-output cross- regulation (see Secondary Feedback Regulation Loop section). Internal VL and REF ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Holding SHDN low puts the IC into its 4µA shutdown mode. SHDN is logic input with a threshold of about 1V (the internal N-channel MOSFET). For auto- TH matic start-up, ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Discharging the output capacitor through the main inductor causes the output to momentarily go below GND. Clamp this negative pulse with a back-biased 1A Schottky diode across the output capacitor (Figure 1). To ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Remote output-voltage sensing, while not possible in fixed-output mode due to the combined nature of the voltage-sense and current-sense inputs (CSL3 and CSL5), is easy adjustable mode by using the ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers sistor can be added. Figure 6’s circuit delivers more than 200mA. Total output current is constrained by the V+ input voltage and the transformer primary load (see Maximum 15V V Output Current vs. ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Current-Sense Resistor Value The current-sense resistor value is calculated according to the worst-case-low current-limit threshold voltage (from the Electrical Characteristics table) and the peak inductor current: 80mV R = SENSE I PEAK Use ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers systems can multiply the R value by a factor of 1.5 ESR without hurting stability or transient response. The output voltage ripple is usually dominated by the filter capacitor’s ESR, and can be ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers 2 PD(upper FET LOAD DS(ON) ⎛ ⎜ IN LOAD ⎝ 2 PD(lower FET LOAD DS(ON) DUTY ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Table 5. Low-Voltage Troubleshooting Chart SYMPTOM Sag or droop in V under Low V OUT step-load change differential, <1.5V Dropout voltage is too high Low V (V follows OUT IN ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers where t is the diode-conduction time (120ns typical) D and V is the forward voltage of the diode. FWD This power is dissipated in the MOSFET body diode if no external Schottky diode ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _______________________________________________________________________________Application Circuits INPUT +5.2V TO +24V C3 ON/OFF 2.7μF C1 +3. OUTPUT * 0.1μF 1:4 (3A) 1N5819 3V ON/OFF 5V ON/OFF 20mΩ 10μH SUMIDA CDRH125-100 ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _____________________________________________________________Application Circuits (continued) INPUT +6.5V TO +28V C3 ON/OFF L1 +3.3V OUTPUT (3A 0.1μF 1N5819 20mΩ 10μH SUMIDA CDRH125-100 T2 = 10μH 1:2.2 TRANSFORMER ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _____________________________________________________________Application Circuits (continued) INPUT +6V TO +24V C3 0.1μ 2.5V OUTPUT * C1 1N5819 0Ω OPEN ON/OFF ON/OFF 15mΩ 6.8μH SUMIDA CDRH 127-6R8MC ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers ________________________________________________________________________________Pin Configurations CSH3 28 1 CSL3 2 27 FB3 3 26 12OUT MAX1630 SYNC 6 MAX1632 23 MAX1633 TIME/ON5 7 22 MAX1635 21 GND ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers __Ordering Information (continued) PART TEMP RANGE MAX1631CAI 0°C to +70°C MAX1631CAI+ 0°C to +70°C MAX1631EAI+ -40°C to +85°C MAX1632CAI 0°C to +70°C MAX1632CAI+ -40°C to +85°C MAX1632EAI+ -40°C to +85°C MAX1633CAI 0°C to ...
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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 © 2005 Maxim Integrated Products ...