MAX1565ETJ Maxim Integrated Products, MAX1565ETJ Datasheet
MAX1565ETJ
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MAX1565ETJ Summary of contents
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... Boost Adjustable Output Down to 1.25V o Three Auxiliary PWM Controllers 1MHz Operating Frequency o 1µA Shutdown Mode o Internal Soft-Start Control o Overload Protection o Compact 32-Pin, 5mm x 5mm Thin QFN Package PART MAX1565ETJ Applications TOP VIEW COMP1 PGNDA LXSD INSD ONSD MAIN +3.3V COMPSD CORE +1 ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply ABSOLUTE MAXIMUM RATINGS OUTSU_, INSD, SDOK, ON_, FB_, FBSEL_ to GND ....................................................-0.3V to +6V PGND to GND .......................................................-0.3V to +0.3V DL_ to PGND...........................................-0.3V to OUTSU + 0.3V LXSU Current (Note 1) ..........................................................3.6A ...
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... P-channel P-Channel Current Limit N-Channel Turn-Off Current Soft-Start Interval SDOK Output Low Voltage FBSD = 0.4V; 0.1mA into SDOK pin SDOK Operating Voltage Range Idle Mode is a trademark of Maxim Integrated Products, Inc. _______________________________________________________________________________________ Digital Still Camera Power Supply CONDITIONS = 0V, OUTSU = 5. 5.5V OUT = 5 ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply ELECTRICAL CHARACTERISTICS (continued 3.3V 0°C to +85°C, unless otherwise noted.) OUTSU A PARAMETER AUXILIARY DC-TO-DC CONTROLLERS (AUX 1, 2, AND 3) Maximum Duty Cycle FB_ = 1V FB_ ...
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Small, High-Efficiency, Five-Channel ELECTRICAL CHARACTERISTICS (continued 3.3V -40°C to +85°C, unless otherwise noted.) OUTSU A PARAMETER Reference Line Regulation 2.7V < OUTSU < 5.5V OSC Discharge Trip Level Rising edge OSC Discharge Resistance OSC = 1.5V, ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply ELECTRICAL CHARACTERISTICS (continued 3.3V -40°C to +85°C, unless otherwise noted.) OUTSU A PARAMETER FB_ to COMP_ FB_ = COMP_ Transconductance FB_ Input Leakage Current FB_ = 1.25V AUX1 ...
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Small, High-Efficiency, Five-Channel (Circuit of Figure +25°C, unless otherwise noted.) A BUCK-BOOST EFFICIENCY vs. LOAD CURRENT (1.5V OUTPUT 3.3V) OUTSU 100 ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply (Circuit of Figure +25°C, unless otherwise noted.) A REFERENCE VOLTAGE vs. TEMPERATURE 1.249 1.248 1.247 1.246 1.245 1.244 1.243 1.242 1.241 1.240 -50 - 100 ...
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Small, High-Efficiency, Five-Channel (Circuit of Figure +25°C, unless otherwise noted.) A STEP-UP LOAD TRANSIENT RESPONSE 0A 0V 400µs/div PIN NAME Auxiliary Controller 1 Compensation Node. Connect a series RC from COMP1 to GND to compensate the 1 ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply PIN NAME Step-Down Converter Feedback Input. For a 1.5V output, short FBSELSD to GND and connect FBSD to 8 FBSD OUTSD. For other voltages, short FBSELSD to OUTSU and connect a resistive ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply PIN NAME Auxiliary Controller 3 Compensation Node. Connect a series resistor-capacitor from COMP3 to GND to 24 COMP3 compensate the control loop. COMP3 is actively driven to GND in shutdown and thermal ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply V IN +1.5V TO +4.2V 20µF 5V 500mA 20µF 0.1 µF 36.5kΩ 100pF 47kΩ 25kΩ 20kΩ 6800pF 10kΩ 3300pF 0.01µF 1000pF Figure 1. Typical Application Circuit 12 ______________________________________________________________________________________ 2µH MAX1565 AUX1 AUX3 ...
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Small, High-Efficiency, Five-Channel V OUTSU 2.35V ONSU VREF 1V ONSU Figure 2. MAX1565 Functional Diagram ______________________________________________________________________________________ Digital Still Camera Power Supply INTERNAL POWER NORMAL OK MODE REFOK DIE OVER TEMP FLTALL 100,000 FAULT CLOCK CYCLE IN FAULT TIMER CLK OSC ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply Detailed Description The MAX1565 is a complete digital still camera power- conversion IC. It can accept input from a variety of sources including single-cell Li+ batteries, 2-cell alkaline or NiMH batteries, as ...
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Small, High-Efficiency, Five-Channel Note that the step-up output supplies both the step-up load and the step-down input current when the step- down is powered from the step-up. The step-down input current reduces the available step-up output cur- rent for other ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply Maximum Duty Cycle The MAX1565 auxiliary PWM controllers have a guaran- teed maximum duty cycle of 80%. That is to say that all controllers can achieve at least 80% and typically reach ...
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Small, High-Efficiency, Five-Channel Low-Voltage Startup Oscillator The MAX1565 internal control and reference-voltage circuitry receive power from OUTSU and do not function when OUTSU is less than 2.5V. To ensure low-voltage startup, the step-up employs a low-voltage startup oscillator that activates ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply The output capacitor keeps output ripple small and ensures control-loop stability. The output capacitor must also have low impedance at the switching fre- quency. Ceramic, polymer, and tantalum capacitors are suitable, with ...
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Small, High-Efficiency, Five-Channel Choose f = 20kHz. Calculate )(R /R )(gm/2π OUT LOAD CS = (1.25/3.35)(6.7/0.3) x (135µS/(6.28 x 20kHz) (2/3.35) = 5.35nF Choose 6.8nF. Now select R such ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply If we select L = 4.7µH and f = 440kHz, P OSC V /(πL) = 214kHz, so choose f = 40kHz and calculate )(R /R ...
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Small, High-Efficiency, Five-Channel Discontinuous Inductor Current When the inductor current falls to zero on each switching cycle described as discontinuous. The inductor is not utilized as efficiently as with continuous current. This often has little negative impact in ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply TO V BATT 1µF 10µH DL_ 1µF WHITE LEDs FB_ 62Ω (FOR 20mA) Figure 6. AUX_ Channel Powering a White LED Step-Up Current Source SEPIC Buck-Boost The MAX1565’s internal switch step-up and ...
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Small, High-Efficiency, Five-Channel L1 10µ BATT C2 1µF 1µF FB_ AUX_ PWM OUTSU C1 Q1 1µF DL_ D1 MAX1565 (PARTIAL) Figure 9. ±15V Output Using a Boost with Charge-Pump Inversion TO V BATT AUX_ PWM MAX1565 (PARTIAL) ...
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Small, High-Efficiency, Five-Channel Digital Still Camera Power Supply V OUT Figure 11. Connecting the MAX1801 Slave PWM Controller to the MAX1565 Using SDOK for Power Sequencing SDOK goes low when the step-down reaches regula- tion. Some microcontrollers with low-voltage cores ...
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Small, High-Efficiency, Five-Channel Designing a PC Board Good PC board layout is important to achieve optimal performance from the MAX1565. Poor design can cause excessive conducted and/or radiated noise. Conductors carrying discontinuous currents, and any high-current path should be made ...
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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. 26 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products ...