MAX668EUB Maxim Integrated Products, MAX668EUB Datasheet
MAX668EUB
Specifications of MAX668EUB
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MAX668EUB Summary of contents
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... Adjustable 100kHz to 500kHz Oscillator or SYNC Input 220µA Quiescent Current Logic-Level Shutdown Soft-Start Cellular Telephones Telecom Hardware LANs and Network Systems POS Systems PART MAX668EUB MAX669EUB Idle Mode is a trademark of Maxim Integrated Products. TOP VIEW V = 28V OUT Features Applications Ordering Information ...
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Input, PWM Step-Up Controllers in µMAX ABSOLUTE MAXIMUM RATINGS V to GND ..........................................................-0.3V to +30V CC PGND to GND....................................................................±0.3V SYNC/SHDN to GND .............................................-0.3V to +30V EXT, REF to GND.....................................-0. LDO, FREQ, FB, CS+ to GND ...
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ELECTRICAL CHARACTERISTICS (continued LDO = 5V 200kΩ OSC A PARAMETER Maximum Duty Cycle Minimum EXT Pulse Width Minimum SYNC Input-Pulse Duty Cycle Minimum SYNC Input Low Pulse Width SYNC Input Rise/Fall Time SYNC Input ...
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Input, PWM Step-Up Controllers in µMAX ELECTRICAL CHARACTERISTICS (continued LDO = 5V 200kΩ -40°C to +85°C, unless otherwise noted.) CC OSC A PARAMETER REF Output Voltage REF Load Regulation REF Undervoltage ...
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Figures and +25°C; unless otherwise noted.) A EFFICIENCY vs. LOAD CURRENT (V = 5V) OUT ...
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Input, PWM Step-Up Controllers in µMAX (Circuits of Figures and +25°C; unless otherwise noted.) A REFERENCE VOLTAGE vs. TEMPERATURE 1.250 1.249 1.248 1.247 1.246 1.245 1.244 1.243 1.242 1.241 V = ...
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Figures and +25°C; unless otherwise noted.) A EXITING SHUTDOWN OUTPUT VOLTAGE 5V/div INDUCTOR CURRENT 2A/div SHUTDOWN VOLTAGE 5V/div 500 s/div MAX668 5V 12V, LOAD = 1.0A ...
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Input, PWM Step-Up Controllers in µMAX PIN NAME 5V On-Chip Regulator Output. This regulator powers all internal circuitry including the EXT gate driver. 1 LDO Bypass LDO to GND with a 1µF or greater ceramic capacitor. Oscillator ...
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The heart of the MAX668/MAX669 current-mode PWM controller is a BiCMOS multi-input comparator that simultaneously processes the output-error signal, the current-sense signal, and a slope-compensation ramp (Figure 1). The main PWM comparator is direct sum- ming, lacking a traditional error ...
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Input, PWM Step-Up Controllers in µMAX V = 1.8V to 12V IN 1 LDO MAX669 0.1 F SYNC/ 10 SHDN 4 REF 2 C3 FREQ 0. 100k 1% ...
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12V IN 1 LDO 0.1 F SYNC/ 10 SHDN 4 REF C3 2 FREQ 0. 100k 1% Figure 4. MAX668 High-Voltage Non-Bootstrapped Configuration V = 2.7V to ...
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Input, PWM Step-Up Controllers in µMAX Table 2. Bootstrapped and Non-Bootstrapped Configurations USE CONFIGURATION FIGURE WITH: High-Voltage, Figure MAX669 Bootstrapped 2 Low-Voltage, Figure MAX669 Bootstrapped 3 High-Voltage, Figure MAX668 Non-Bootstrapped 4 Low-Voltage, Figure MAX668 Non-Bootstrapped 5 Extra ...
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SHDN and FREQ Inputs SYNC/ The SYNC/SHDN pin provides both external-clock syn- chronization (if desired) and shutdown control. When SYNC/SHDN is low, all IC functions are shut down. A logic high at SYNC/SHDN selects operation at a fre- quency set ...
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Input, PWM Step-Up Controllers in µMAX given output ripple. An inductance value larger than L may also be used, but output-filter capacitance IDEAL must be increased by the same proportion that L has See ...
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Since output ripple in boost DC-DC designs is dominated by capacitor equivalent series resistance (ESR), a capaci- tance value times larger than C cally needed. Low-ESR types must be ...
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Input, PWM Step-Up Controllers in µMAX larger or smaller than the output voltage, such as when converting four NiMH, NiCd, or Alkaline cells output. The SEPIC configuration is often a good choice for combined ...
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V = +5V IN 220 10V 0.22 F T1: COILTRONICS CTX03-14232 Figure 7. Isolated 400mA Power Supply ______________________________________________________________________________________ 1.8V to 28V Input, PWM Step-Up T1 1:2 LDO V CC IRF7603 EXT SHDN CS+ ...
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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. 18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products ...