MAX1808EUB+ Maxim Integrated, MAX1808EUB+ Datasheet
MAX1808EUB+
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MAX1808EUB+ Summary of contents
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Low-Cost, Small, 4.5V to 28V Wide Operating Range, DC-DC Synchronous Buck Controller General Description The MAX15026 synchronous step-down controller oper- ates from a 4.5V to 28V input voltage range and gener- ates an adjustable output voltage from 85% of the ...
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... A = +25°C.) (Note 2) A MIN TYP 4.5 4.5 1.75 290 480 375 5.0 5.25 < 70mA 100 200 3.8 4.0 400 585 591 -250 600 1200 80 4 160 50 80 MAX UNITS 28 V 5.5 2.75 mA 500 µA µs µs 5.5 V 0.28 V 300 mA 4 597 mV +250 nA 1800 µS dB MHz mV 110 µA Maxim Integrated ...
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... DRV Undervoltage Lockout Hysteresis DH On-Resistance DL On-Resistance DH Peak Current DL Peak Current DH/DL Break-Before-Make Time DL/DH Break-Before-Make Time SOFT-START Soft-Start Duration Reference Voltage Steps CURRENT LIMIT/HICCUP Current-Limit Threshold Adjustment Range Maxim Integrated = 4.7µ 1µ -40°C to +85°C (MAX15026B/CETD+, MAX15026BETD/V+), VCC IN A CONDITIONS V V rising EN_H EN V ...
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... SW = +25°C.) (Note 2) A MIN TYP MAX 45 50 2300 7 4096 8192 4096 94 5V +150 20 UNITS 55 µA ppm/°C Events Switching Cycles Switching Cycles Switching Cycles mV Ω µA 0.4 V °C °C Maxim Integrated ...
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... LOAD CURRENT (mA) SWITCHING FREQUENCY vs. RESISTANCE 2500 2000 1500 1000 500 RESISTANCE (kΩ) Maxim Integrated Typical Operating Characteristics EFFICIENCY vs. LOAD CURRENT (V = 12V DRV 100 OUT 3.3V OUT 1.8V OUT ...
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... POWER-DOWN FALL TIME V IN 5V/div V OUT 1V/div 4ms/div OUTPUT SHORT-CIRCUIT BEHAVIOR MONITOR OUTPUT VOLTAGE AND CURRENT V IN 5V/div V OUT V OUT 1V/div I OUT 4ms/div Maxim Integrated MAX15026 toc12 AC-COUPLED 10A 1A MAX15026 toc15 V IN 5V/div V OUT 1V/div MAX15026 toc18 500mV/div 0 20A/div 0 ...
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... High-Side Gate-Driver Output. DH swings from LX to BST low during UVLO. Exposed Pad. Internally connected to GND. Connect large copper plane at GND potential to — EP improve thermal dissipation. Do not use EP as the only GND ground connection. Maxim Integrated FUNCTION to GND with a minimum of 4.7µF low-ESR ceramic CC to GND when V supplies the device core quiescent current with a 2.2µ ...
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... HICCUP TIMEOUT HICCUP LOGIC DH_DL_ENABLE PWM COMPARATOR RAMP GENERATOR RAMP GATEP BOOST DRIVER HIGH- SIDE PWM DRIVER HICCUP CONTROL LOGIC LOW- SIDE DRIVER LIM/20 SINK ENABLE V REF VALLEY PGOOD COMPARATOR LIM/10 COMP PWM BST DH LX DRV DL GND FB PGOOD GND Maxim Integrated ...
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... The voltage at COMP sets the duty cycle using a PWM comparator and a ramp generator. On the rising edge of an internal clock, the high-side n-channel MOSFET turns on and remains on until either the appropriate duty cycle Maxim Integrated MAX15026 or the maximum duty cycle is reached. During the on- time of the high-side MOSFET, the inductor current ramps up ...
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... DH and DL do not start switching until the PWM comparator commands the first PWM pulse. The first PWM pulse occurs when the ramping reference voltage increases above the FB voltage. for always-on operation. Owing to CC Power-Good Output (PGOOD) Startup into a Prebiased Output Maxim Integrated ...
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... The valley current-limit threshold across the low-side MOSFET is precisely 1/10th of the voltage at LIM, while the sink current-limit threshold is 1/20th of the voltage at LIM. Maxim Integrated D E 2048 CLK CYCLES ...
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... DROP2 Setting the Output Voltage from between 1kΩ and 50kΩ. Calculate ⎡ ⎤ ⎛ ⎞ V OUT = ⎢ ⎥ − 1 ⎝ ⎜ ⎠ ⎟ ⎢ ⎥ V ⎣ ⎦ FB can range from 0.591V to (0. Maxim Integrated DROP1 is the ). IN and ...
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... I high for very low LIR values. A good compromise between size and loss is a 30% peak-to-peak ripple cur- rent to average-current ratio (LIR = 0.3). The switching Maxim Integrated frequency, input voltage, output voltage, and selected LIR determine the inductor value as follows, OUT ...
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... C OUT ∆ ∆ × STEP = ESL I STEP 1 ≅ t RESPONSE × the load step the rise time of the STEP STEP is the response time of the con- RESPONSE is the closed-loop crossover frequency. O Compensation ) of the capaci- Maxim Integrated ...
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... Choose Type III (PID—proportional, integral and derivative) compensation network. Maxim Integrated lower than the capacitor ESR zero almost cancels the phase loss of one of the complex poles of the LC filter around the crossover frequency. Use a Type II compensation network with a midband zero and a high-frequency pole to stabilize the loop ...
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... × MOD V RAMP × MOD ( ) 2 V π × × RAMP OUT REF ), use 0 × 2π ), comprises MOD 1 × OUT OUT C F COMP Maxim Integrated ...
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... Z2 whichever is lower, and calculate R lowing equation π × × Maxim Integrated ) in midband fre- 5) Place the third pole (f EA quency and calculate Calculate R EA × L OUT OUT The MAX15026 step-down controller drives two external logic-level n-channel MOSFETs ...
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... FB). Group all GND-referred and feedback compo nents close to the device. Keep the FB and compensation network as small as possible to prevent noise pickup. ) when actual C x θ thermal impedance for the 14-pin JC PCB Layout Guidelines bypass capacitor, com- IN capaci- CC Maxim Integrated ...
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... C1 PANASONIC 330µF EEEFCIE331P PGOOD ENABLE 4.02kΩ 68pF 68pF C9 0.022µF R1 11.8kΩ C10 4.7µF Figure 4.5V to 28V IN Maxim Integrated Typical Application Circuits Single 4.5V to 28V Supply Operation IN DH MAX15026 0.47µF PGOOD BST LIM DL R1* EN DRV C6 2.2µF COMP GND ...
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... Figure 6 shows an application circuit for a single 4.5V to 5.5V power-supply operation. 4. PGOOD ENABLE LIM Figure 4. DRV 20 Typical Application Circuits (continued) Single 4.5V to 5.5V Supply Operation IN DH MAX15026 PGOOD BST DL LIM EN DRV C1 GND COMP BST Maxim Integrated V OUT ...
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... Figure 7 shows an application circuit for a +12V supply to drive the external MOSFETs and an auxiliary +5V supply to power the device. PGOOD ENABLE LIM V AUX 4.5V TO 5.5V Figure 7. Operation with Auxiliary 5V Supply Maxim Integrated Typical Application Circuits (continued MAX15026 BST PGOOD DL LIM EN DRV ...
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... RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE PACKAGE OUTLINE NO. TYPE CODE 14 TDFN-EP T1433+2 21-0137 LAND PATTERN NO. 90-0063 Maxim Integrated ...
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... Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed ...