MAX746CSE Maxim Integrated Products, MAX746CSE Datasheet
MAX746CSE
Specifications of MAX746CSE
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MAX746CSE Summary of contents
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... Idle-Mode PFM (Light Loads scheme Cycle-by-Cycle Current Limiting 2V ±1.5% Accurate Reference Output Adjustable Soft-Start Undervoltage Lockout Precision Comparator for Power-Fail or Low-Battery Warning ______________Ordering Information PART MAX746CPE MAX746CSE MAX746C/D MAX746EPE MAX746ESE MAX746MJE * Contact factory for dice specifications. __________________Pin Configuration TOP VIEW 40m LBO LBI SS ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller ABSOLUTE MAXIMUM RATINGS Supply Voltage V+, AV+ to GND ..............................-0.3V to 17V HIGH, EXT to GND....................................................-0.3V to 21V AGND to GND..........................................................-0.3V to 0.3V All Other Pins................................................-0.3V to (V+ + 0.3V) Reference Current (I ) ...
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High-Efficiency, PWM, Step-Down, ELECTRICAL CHARACTERISTICS (continued) (V+ = 10V 0A LOAD REF A MIN PARAMETER SYMBOL Maximum Duty Cycle Charge-Pump Output Voltage V HIGH Current-Sense Amplifier V LIMIT Current-Limit Threshold EXT ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller __________________________________________Typical Operating Characteristics (Circuit of Figure 1a +25°C, unless otherwise noted.) A N0-LOAD SUPPLY CURRENT vs. SUPPLY VOLTAGE 1.2 1.1 1.0 0.9 0 SUPPLY VOLTAGE (V) ...
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High-Efficiency, PWM, Step-Down, ____________________________Typical Operating Characteristics (continued) (Circuit of Figure 1a +25°C, unless otherwise noted.) A LOAD-TRANSIENT RESPONSE A B 200 s/div A: LOAD CURRENT, 0.1A TO 1.5A, 1A/div B: V RIPPLE, 50mV/div, AC-COUPLED OUT V+ = 10V ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller ______________________________________________________________Pin Description PIN NAME Low-battery output is an open-drain output that goes low when LBI is less than 2V. Connect to V+ through a 1 LBO pull-up resistor. Leave floating if not used. LBO ...
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High-Efficiency, PWM, Step-Down 15V C3 0 0 SEE TABLE 2 FOR DIODE SELECTION. Figure 1a. 5V Standard Application Circuit (15W) Discontinuous-/Continuous- Conduction Modes The MAX746 is designed to operate ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller 0.1 F 100 LBI MAX746 REF 5 SHDN 11 AGND GND 16 ...
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High-Efficiency, PWM, Step-Down 15V SEE TABLE 2 FOR DIODE SELECTION. ** SUMIDA CDR125 SURFACE-MOUNT INDUCTOR. Figure 1c. 5V Standard Application Circuit (7.5W) The steady-state ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller LBO LBI N LOW-BATTERY COMPARATOR REF OUT CC FB DUAL-MODE COMPARATOR 100mV CURRENT-SENSE AMPLIFIER AV+ CS SLOPE- COMPENSATION RAMP SOFT-START SS CIRCUITRY CURRENT-LIMIT COMPARATOR Figure 2. Block Diagram 10 ______________________________________________________________________________________ EXT HIGH FROM AV+ ...
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High-Efficiency, PWM, Step-Down, 3a. CHARGE-PUMP VOLTAGE DOUBLER 1N914 1N914 0.1 F MAX746 T FLIP FLOP CLK HIGH 13 100kHz OSCILLATOR 5V 3b. CHARGE-PUMP AV+ VOLTAGE TRIPLER GND D4 16 ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller MAX746 9 OUT R4 = 10k GND REF * SEE COMPENSATION CAPACITOR SECTION. Figure 6. Adjustable Output Circuit Next, determine the ...
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High-Efficiency, PWM, Step-Down, External Logic-Level N-FET Selection To ensure the external N-FET is turned on hard, use logic-level or low-threshold N-FETs. Three important parameters to note when selecting the N-FET are the total gate charge ( resistance (r ...
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High-Efficiency, PWM, Step-Down, N-Channel DC-DC Controller Table 1. Measured Output Voltage Sag with 30mA to 3A Load Step* OUTPUT OUTPUT VOLTAGE SAG (mV) FILTER FOR VARIOUS INPUT VOLTAGES CAPACITOR =6V V =6.5V V =7V IN ...
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High-Efficiency, PWM, Step-Down, Increasing 50% enhances outer-loop stability by adding stability to the inductor current waveform. But increasing C7 too much causes FB’s response time to decrease (due to the larger RC time constant caused by ...
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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. 16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 © 1993 Maxim Integrated Products ...