MAX5942BESE+T Maxim Integrated Products, MAX5942BESE+T Datasheet
MAX5942BESE+T
Specifications of MAX5942BESE+T
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MAX5942BESE+T Summary of contents
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... Power-Over-MDI Typical Operating Circuit appears at end of data sheet. IEEE is a trademark of the Institute of Electrical and Electronics Engineers. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com. IEEE 802.3af Power-Over-Ethernet ♦ Powered Device Interface Fully Integrated IEEE 802 ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices ABSOLUTE MAXIMUM RATINGS (All voltages are referenced unless otherwise noted.) EE GND........................................................................-0.3V to +90V OUT, PGOOD ...........................................-0.3V to (GND + 0.3V) RCL, GATE .............................................................-0.3V to +12V UVLO ........................................................................-0.3V to ...
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Interface/PWM Controller for Power Devices ELECTRICAL CHARACTERISTICS (continued 48V, GATE = PGOOD = PGOOD = OPEN, V- tied to OUT, V+ tied to GND, UVLO = (GND - unless otherwise noted. Typical ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices ELECTRICAL CHARACTERISTICS (PWM Controller) (continued) (All voltages referenced to V 13V, a 10µF capacitor connects V DD SS_SHDN, NDRV = open circuit 3V PARAMETER SYMBOL I ...
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Interface/PWM Controller for Power Devices ELECTRICAL CHARACTERISTICS (PWM Controller) (continued) (All voltages referenced to V 13V, a 10µF capacitor connects V DD SS_SHDN, NDRV = open circuit 3V PARAMETER SYMBOL SOFT-START SS Source Current ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices (V = (GND - 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = Typical values are +25°C. All voltages are ...
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Interface/PWM Controller for Power Devices (V = (GND - 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = Typical values are +25°C. All voltages are referenced to V ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices (V = (GND - 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = Typical values are +25°C. All voltages are ...
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Interface/PWM Controller for Power Devices (V = (GND - 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = Typical values are +25°C. All voltages are referenced to V ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices PIN NAME tag e S tar tup Inp ut. Refer enced onnect ectl ...
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Interface/PWM Controller for Power Devices Table 1. PD Power Classification/R CLASS USAGE 0 Default 1 Optional 2 Optional 3 Optional 4 Not allowed *Class 4 reserved for future use. Detailed Description The MAX5942A/MAX5942B integrate a complete power IC for powered ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices Table 2. Setting Classification Current CLASS R (Ω ( 10k 12 732 12 392 12 255 12.6 to ...
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Interface/PWM Controller for Power Devices The PSE determines the class applying a volt- age at the PD input and measures the current sourced out of the PSE. When the PSE applies a voltage between 12.6V and ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices Thermal Dissipation During classification mode, if the PSE applies the maxi- mum DC voltage, the maximum voltage drop from GND to V will be 13V. If the maximum classification cur- RCL rent ...
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Interface/PWM Controller for Power Devices HIGH- VOLTAGE V- REGULATOR EN MAX5942A ONLY COMPENSATION 26mV/µs 26mV/µs 1MΩ 50kΩ FB ERROR AMP SS_SHDN 2.4V 0.25V Figure 4. MAX5942A/MAX5942B PWM Controller Functional Diagram ______________________________________________________________________________________ IEEE 802.3af Power-Over-Ethernet IN BIAS ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices V IN (36V TO 72V 4.7µF C 25.5kΩ 10µ 0.1µF Figure 5. Forward Converter Current-Sense Comparator The current-sense (CS) comparator and its associated logic limit ...
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Interface/PWM Controller for Power Devices 25.5kΩ Figure 6. Flyback Converter 25.5kΩ Figure 7. Flyback Converter ______________________________________________________________________________________ IEEE 802.3af Power-Over-Ethernet N V+ GND V DD ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices PWM Comparator and Slope Compensation An internal 275kHz oscillator determines the switching frequency of the controller. At the beginning of each cycle, NDRV switches the N-channel MOSFET on. NDRV switches the external ...
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Interface/PWM Controller for Power Devices V = Output voltage (5V). OUT V = Voltage drop across D1 (typically 0.5V for D1 power Schottky diodes Minimum value of maximum operating duty MAX cycle (44%). V = Minimum input voltage ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices Table 3. Component Suppliers COMPONENT Power FETS Current-Sense Resistors Diodes Capacitors Magnetics 6) Choose R according to the following equation: SENSE V ILIM R ≤ SENSE N S × ...
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Interface/PWM Controller for Power Devices RJ- POWER-OVER SPARE PAIRS GND **R1 SMBJ58CA R = DISC 25.5kΩ 68nF 60V **R2 -48V * OPTIONAL AND R2 ARE OPTIONAL AND WHEN USED, THEY ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices POWER-SUPPLY CIRCUIT 1 GND ** DISC 25.5kΩ 68nF 60V ** -48V POWER-SUPPLY CIRCUIT 2 *OPTIONAL. **R1 AND R2 ARE OPTIONAL AND WHEN USED, THEY MUST TOTAL TO 25.5kΩ ...
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IEEE 802.3af Power-Over-Ethernet Interface/PWM Controller for Power Devices GND R = DISC 25.5kΩ 60V -48V ______________________________________________________________________________________ V+ GND NDRV MAX5942 SS_SHDN PGOOD UVLO RCL PGOOD GATE FB V OUT EE C GATE TRANSISTOR COUNT: ...
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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. 24 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2004 Maxim Integrated Products H ...