MAX5981A MAXIM [Maxim Integrated Products], MAX5981A Datasheet
MAX5981A
Related parts for MAX5981A
MAX5981A Summary of contents
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... The MAX5981 also features an LED driver that is auto- matically activated during sleep mode. During sleep mode, the LED driver sources a peri odic current (I 250Hz (MAX5981A) or 15.625kHz (MAX5981B). The MAX5981 is available in a 16-pin, 5mm x 5mm TQFN power package. The device is rated over the -40°C to +85° ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with ABSOLUTE MAXIMUM RATINGS ..........................................................-0.3V to +100V DD SS DET, RTN, WAD, PG, 2EC to V ....................... -0.3V to +100V SS CLS, SL, WK, ULP, LED to V ...............................-0.3V to +6V ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with ELECTRICAL CHARACTERISTICS (continued 48V 24.9kω DET voltages are referenced to V unless otherwise noted +25 C.) ...
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... Note 6: Classification current is turned off whenever the device is in power mode. Note 7: UVLO hysteresis is guaranteed by design, not production tested. Note 8: A 20V glitch on input voltage, which takes V MAX5981A/MAX5981B to exit power-on mode. Note 9: In power mode, current-limit foldback is used to reduce the power dissipation in the isolation MOSFET during an overload condition across V and RTN ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with ( 54V 24.9kω DET voltages are referenced SS. DETECTION CURRENT vs. INPUT VOLTAGE 0 ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with ( 54V 24.9kω DET voltages are referenced SS. NORMAL OPERATION CURRENT LIMIT vs. RTN VOLTAGE 900 800 700 ...
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... The PG current sink is turned on to disable the downstream DC-DC converter when the device is in sleep mode. _______________________________________________________________________________________ Integrated Power MOSFET N. MAX5981A MAX5981B DET 3 10 EP* I. TQFN FUNCTION DET connects to the source of the integrated isolation n-channel power MOSFET. ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with PIN NAME 2-Event Classification Detect or Wall Adapter Detect Output. A 1.5mA current sink is enabled at 2EC when a Type 2 PSE or a wall adapter is detected. When powered by a ...
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... ULP _______________________________________________________________________________________ Integrated Power MOSFET DD D SET Q D SET Q CLR Q CLR Q 5V THERMAL SHUTDOWN DELAY ISOLATION SWITCH S I0 MAX5981A I1 MAX5981B MUX Simplified Block Diagram CLASSIFICATION 1.5mA OFF 230µ LOGIC CLS 2EC PG WAD RTN LED 9 ...
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... BRIDGE R DET RECTIFIER 24.9kI DET 68nF CLS SMAJ58A R CLS V -54V LED -54V 10 _____________________________________________________________________________________ Integrated Power MOSFET V 2EC DD PG 2EC/WAD MAX5981A WAD MAX5981B 1.5mA 24V/48V BATTERY RTN ULP Typical Operating Circuit 2-EVENT CLASSIFICATION DETECTION IN+ GND ENABLE DC-DC CONVERTER IN- 1kI ISOLATED SLEEP MODE INPUT ...
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... MAX5981A/MAX5981B pres ent the mark current (I ). This sequence is repeated one more time. MARK When the MAX5981A/MAX5981B are pow ered by a Type 2 PSE, the 2-Event identification output 2EC asserts low after the internal isolation n-channel MOSFET is fully turned on. 2EC current sink is turned off when V ...
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... The ultra-low-power enable input ULP is internally held high with a 50kI pullup resistor to the internal 5V bias of the MAX5981A/MAX5981B. Set ULP to logic-low and apply a falling edge enable ultra-low-power sleep mode. Apply a falling edge on the wake-mode enable input (WK) to disable sleep or ultra-low-power sleep mode and resume normal operation ...
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... Figure 2. Typical Configuration When Using a 12V Wall Power Adapter ______________________________________________________________________________________ Integrated Power MOSFET 3) Use short and wide traces for high-power paths. 4) Use the MAX5981A/MAX5981B evaluation kit layout as a reference. Layout Procedure 5) Place enough vias in the pad for the EP of the MAX5981A/MAX5981B so that heat generated inside can be effectively dissipated by the PCB copper ...
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... GND 33kI 1.37MI 51.5kI PG ULVO/EN UFLG FB 10kI COMP CS CS 4.99kI 14 _____________________________________________________________________________________ Integrated Power MOSFET V 2EC DD PG 24.9kI 2EC/WAD DET 68nF WAD MAX5981A 1.4mA MAX5981B CLS 24/48V BATTERY 43.7I V RTN ULP LED 249I 4.7µF 0.1µF GND RTN IN 0.1µF 0.1µF 22µ ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with Chip Information PROCESS: BiCMOS ______________________________________________________________________________________ Integrated Power MOSFET Package Information For the latest package outline information and land patterns, (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package ...
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IEEE 802.3af/at-Compliant, Powered Device Interface Controllers with REVISION REVISION NUMBER DATE 0 1/11 Initial release Revised General Description, Absolute Maximum Ratings, Electrical 1 8/11 Characteristics, Pin Description, Typical Operating Circuit, LED Driver section, and Typical Application Circuit. Revised General Description, ...