MAX1630CAI Maxim Integrated Products, MAX1630CAI Datasheet
MAX1630CAI
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MAX1630CAI Summary of contents
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... Low-Dropout, 99% Duty-Factor Operation 2.5mW Typical Quiescent Power (+12V input, both SMPSs on) 4µA Typical Shutdown Current 28-Pin SSOP Package _______________Ordering Information PART TEMP. RANGE MAX1630CAI 0°C to +70°C MAX1630EAI -40°C to +85°C Ordering Information continued on last page. ________________Functional Diagram INPUT +5V (RTC) ...
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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 +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 ...
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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 0.6V TIME/ON5 Figure 2. MAX1632 Block Diagram 10 ______________________________________________________________________________________ SHDN V+ SYNC CSL5 - ...
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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 LOAD 2 PD(lower FET LOAD DS(ON) DUTY = (V + ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers Table 5. Low-Voltage Troubleshooting Chart SYMPTOM CONDITION 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 ...
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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 +3. OUTPUT * 0.1 F 1:4 (3A) 1N5819 3V ON/OFF 5V ON/OFF 20m ...
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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 0.1 F 1N5819 3V ON/OFF 5V ON/OFF 20m SUMIDA ...
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Multi-Output, Low-Noise Power-Supply Controllers for Notebook Computers _____________________________________________________________Application Circuits (continued) INPUT +6V TO +24V C3 0 2.5V OUTPUT * C1 1N5819 0 OPEN ON/OFF ON/OFF 15m 6.8 H SUMIDA ...
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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 8 REF 9 ...
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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. 28 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 1997 Maxim Integrated Products PIN-PACKAGE ...