MAX256ASA+T Maxim Integrated Products, MAX256ASA+T Datasheet
MAX256ASA+T
Specifications of MAX256ASA+T
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MAX256ASA+T Summary of contents
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... MODE ST2 CK_RS 47kΩ GND +5V TO ISOLATED +5V TYPICAL APPLICATION ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. for Isolated Supplies ♦ Provides the Transformer in Isolated Power Supplies ♦ Single Supply +5V or +3.3V Operation ♦ ...
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Primary-Side Transformer H-Bridge Driver ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND, unless otherwise noted.) Supply Voltage V ..................................................-0.3V to +6V CC ST1, ST2, CK_RS, MODE (Note 1)................-0. ST1, ST2 Maximum Continuous Current (T ST1, ST2 Maximum ...
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Primary-Side Transformer H-Bridge Driver TIMING CHARACTERISTICS (V = +3.0V to +5.5V MIN MAX PARAMETER SYMBOL Switching Frequency CK_RS Input Frequency ST1 and ST2 Duty Cycle Crossover Dead Time Watchdog Timeout Note 2: ...
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Primary-Side Transformer H-Bridge Driver (V = +5.0V ±10 +25°C, unless otherwise noted.) (See Figure 8A SUPPLY CURRENT vs. OSCILLATOR FREQUENCY 100 200 300 400 500 600 700 ...
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Primary-Side Transformer H-Bridge Driver (V = +5.0V ±10 +25°C, unless otherwise noted.) (See Figure 8A OPERATION AT 100kHz 1µs/div V CC OSC CK_RS 165kΩ MODE _______________________________________________________________________________________ for Isolated Supplies Typical Operating Characteristics (continued) CK_RS 5V/div ...
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Primary-Side Transformer H-Bridge Driver Detailed Description The MAX256 is an integrated primary-side controller and H-bridge driver for isolated power-supply circuits. The device contains an on-board oscillator, protection circuitry, and internal FET drivers to provide power ...
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Primary-Side Transformer H-Bridge Driver Table 1. Oscillator Modes OSCILLATOR MODE Internal Unconnected or pulled to ground by R Programmable be greater than 10kΩ. Frequency Digital input. Drive CK_RS with an external clock External Clock signal. Connected ...
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Primary-Side Transformer H-Bridge Driver these circuits. Place R as close as possible to the S CK_RS pin. An additional capacitance of 100nF from CK_RS to GND may be required in some applications. Output Voltage Regulation For many applications, the ...
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Primary-Side Transformer H-Bridge Driver 4.7µF 470nF MODE CK_RS 300kΩ Figure 2. +3.3V to Isolated Regulated +5V 4.7µF 470nF MODE CK_RS 100kΩ Figure 3. +5V to Isolated Regulated +3.3V 4.7µF 470nF MODE CK_RS 100kΩ Figure 4. +5V to Isolated Regulated ...
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Primary-Side Transformer H-Bridge Driver +5V 4.7µF 470nF V CC MODE MAX256 CK_RS 47kΩ GND Figure 5. +5V to Isolated Regulated ±15V Component Selection Transformer Selection Transformer selection for the MAX256 can be simplified by the use of a design ...
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Primary-Side Transformer H-Bridge Driver RS485 Figure 6. Isolated Power Supply for Process Control Applications As with all power-supply designs important to opti- mize efficiency. In designs incorporating small trans- formers, the possibility of thermal runaway makes low ...
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Primary-Side Transformer H-Bridge Driver FILTER L1 25µH OUTPUT C1 2.2µF Figure 7. Output Ripple Filter +5V 4.7µF 470nF 1:2.6CT ST1 MAX256 MODE ST2 CK_RS 47kΩ GND Figure 8a. +5V to Isolated +5V +3.3V 4.7µF 470nF 1:2 ST1 MAX256 MODE ...
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Primary-Side Transformer H-Bridge Driver Table 2. Suggested External Component Manufacturers MANUFACTURER Central Semiconductor Halo Electronics Kemet Sanyo Taiyo Yuden TDK Output-Ripple Filtering Output voltage ripple can be reduced with a lowpass LC pi-filter (Figure 7). The component values shown ...
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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. 14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2005 Maxim Integrated Products Campillo Printed USA is a registered trademark of Maxim Integrated Products, Inc ...