MAX5940BESA+T Maxim Integrated Products, MAX5940BESA+T Datasheet
MAX5940BESA+T
Specifications of MAX5940BESA+T
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MAX5940BESA+T Summary of contents
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... D1* GND D2* -48V *OPTIONAL. Typical Operating Circuits continued at end of data sheet. ________________________________________________________________ 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 Power-Over-Ethernet ♦ Fully Integrated IEEE 802.3af-Compliant PD Interface ♦ PD Detection and Programmable Classification Signatures ♦ ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet ABSOLUTE MAXIMUM RATINGS (All voltages are referenced unless otherwise noted.) EE GND (MAX5940A/MAX5940B) ...............................-0.3V to +80V GND (MAX5940C/MAX5940D)...............................-0.3V to +90V OUT, PGOOD ...........................................-0.3V to (GND + 0.3V) RCLASS, GATE ......................................................-0.3V ...
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IEEE 802.3af PD Interface Controller ELECTRICAL CHARACTERISTICS (continued 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = (GND - Typical values are +25°C. All voltages are ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet I OFFSET Figure1. Effective Differential Input Resistance/Offset Current ) = 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = (GND - are at T ...
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IEEE 802.3af PD Interface Controller ) = 48V, GATE = PGOOD = PGOOD = OUT = OPEN, UVLO = (GND - are +25°C. All voltages are referenced PGOOD ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet PIN NAME MAX5940A/ MAX5940B/ MAX5940C MAX5940D 1, 7 — N.C. No Connection. Not internally connected. Undervoltage Lockout Programming Input for Power Mode. When UVLO is above its threshold, the device enters power mode. ...
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IEEE 802.3af PD Interface Controller 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. Table 2. Setting Classification Current CLASS R (Ω (V) ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet GND 2.46V UVLO REF GND (UVLO) 200mV GATE ( ) MAX5940B. Figure 2. Block Diagram To adjust the UVLO threshold (MAX5940B/MAX5940D only), connect an external resistor-divider from GND to UVLO ...
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IEEE 802.3af PD Interface Controller Inrush Current Limit The MAX5940_ charge the gate of the internal MOSFET with a constant current source (10µA, typ). The drain- to-gate capacitance of the MOSFET limits the voltage rise rate at the drain, thereby ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet POWER-OVER SIGNAL PAIRS RJ- POWER-OVER SPAIR PAIRS GND R DISC R1* 25.5kΩ 60V 68nF R2* -48V *R1 AND R2 ARE OPTIONAL AND WHEN USED, THEY ...
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IEEE 802.3af PD Interface Controller Application Circuit 2 Diode D1 prevents the power-over-ethernet to back drive the wall adapter. Whenever the wall adapter power is greater than (V + approximately 2V), the D3 GND R DISC 25.5kΩ 60V 68nF R ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet Application Circuit 3 D2 prevents the wall adapter power from polluting the discovery and classification signatures. The optional GND R DISC 25.5kΩ 60V 68nF R CL -48V D1 WALL ADAPTER SUPPLY Figure 6. ...
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IEEE 802.3af PD Interface Controller Application Circuit 4 If the wall adapter supply comes up first, it provides power to the load and pollute the discovery and classi- GND R DISC 25.5kΩ 60V 68nF R CL -48V D1 WALL ADAPTER ...
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IEEE 802.3af PD Interface Controller For Power-Over-Ethernet D1* GND R DISC R1** 25.5kΩ 60V 68nF R2** D2* -48V *OPTIONAL. **R1 AND R2 ARE OPTIONAL AND WHEN USED, THEY MUST TOTAL 25.5kΩ AND REPLACE THE 25.5kΩ RESISTOR. Pin Configurations TOP VIEW ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2006 Maxim Integrated Products ...