MAX5988BEVKIT# Maxim Integrated, MAX5988BEVKIT# Datasheet
MAX5988BEVKIT#
Specifications of MAX5988BEVKIT#
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MAX5988BEVKIT# Summary of contents
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IEEE 802.3af-Compliant, High-Efficiency, Class 1/Class 2, Powered Devices with Integrated DC-DC Converter General Description The MAX5988A/MAX5988B provide a complete power- ® supply solution as IEEE 802.3af-compliant Class 1/ Class 2 Powered Devices (PDs Power-over-Ethernet (PoE) system. The devices ...
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... Resistance CLASSIFICATION MODE Classification Enable Threshold Classification Disable Threshold Classification Stability Time Classification Current POWER MODE V DD Supply Voltage Range V DD Supply Current Maxim Integrated MAX5988A/MAX5988B VDRV to V PGND to GND ......................................................-0.3V to +0.3V LX Total RMS Current ...........................................................1.6A = 3.3kω) (Note 1) TEST Continuous Power Dissipation (T + 0.3V) DD TQFN (derate 28 ...
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... LOGIC WAD Detection Rising Threshold WAD Detection Falling Threshold WAD Detection Hysteresis WAD Input Current CLASS2, MPS Voltage Rising Threshold Maxim Integrated , SL, ULP, WK, RESET, LDO_OUT unconnected, WAD = LDO_EN = LDO_IN = PGND = GND, Figure 3 0V, LX unconnected, CLASS2 = 0V, MPS = 0V. All voltages are refer- FB ...
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... Thermal Shutdown Threshold Thermal Shutdown Hysteresis LDO Input Voltage Range Output Voltage Max Output Voltage Setting LDO FB Regulation Voltage Maxim Integrated , SL, ULP, WK, RESET, LDO_OUT unconnected, WAD = LDO_EN = LDO_IN = PGND = GND, Figure 3 0V, LX unconnected, CLASS2 = 0V, MPS = 0V. All voltages are refer- FB AUX = T = -40° ...
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... Soft-Start Time FEEDBACK (FB) FB Regulation Voltage FB Input Bias Current OUTPUT VOLTAGE Output Voltage Range Cycle-by-Cycle Overvoltage Protection Maxim Integrated MAX5988A/MAX5988B , SL, ULP, WK, RESET, LDO_OUT unconnected, WAD = LDO_EN = LDO_IN = PGND = GND, Figure 3 0V, LX unconnected, CLASS2 = 0V, MPS = 0V. All voltages are refer- FB AUX = T = -40° ...
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... Cause HICCUP HICCUP Timeout Minimum On-Time LX Dead Time RESET V FB Threshold for RESET Assertion V FB Threshold for RESET Deassertion Maxim Integrated , SL, ULP, WK, RESET, LDO_OUT unconnected, WAD = LDO_EN = LDO_IN = PGND = GND, Figure 3 0V, LX unconnected, CLASS2 = 0V, MPS = 0V. All voltages are refer- FB AUX = T = -40° ...
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... Note 8 Referred to feedback regulation voltage. Note 9: Referred to LDO feedback regulation voltage. R TEST 1ms/10ms /100ms 100V Figure 1. MAX5988A–MAX5988D Internal TVS Test Setup Maxim Integrated MAX5988A/MAX5988B , SL, ULP, WK, RESET, LDO_OUT unconnected, WAD = LDO_EN = LDO_IN = PGND = GND, Figure 3 0V, LX unconnected, CLASS2 = 0V, MPS = 0V. All voltages are refer- ...
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... SUPPLY VOLTAGE (V) INRUSH CURRENT LIMIT vs. V VOLTAGE (V) CC Maxim Integrated MAX5988A/MAX5988B Typical Operating Characteristics QUIESCENT CURRENT vs. SUPPLY VOLTAGE (ULTRA-LOW POWER MODE) 4.00 3.75 3.50 3.25 3.00 2.75 2.50 10 SUPPLY VOLTAGE (V) CLASSIFICATION CURRENT vs. INPUT VOLTAGE CLASS2 ...
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... V = 36V 0.1 0.2 0.3 0.4 0.5 0.6 LOAD CURRENT (A) 5V LOAD TRANSIENT (0% TO 50%) 100µs/div DC-DC CONVERTER STARTUP I OUT 2ms/div Maxim Integrated Typical Operating Characteristics (continued) = 5V) OUT V = 12V 57V IN = 48V 0.7 0.8 0.9 1.0 MAX5988A toc12 V OUT AC-COUPLED 50mV/div I OUT 500mA /div MAX5988A toc14 ...
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... LDO_IN and GND. 5 LDO_OUT LDO Output Voltage. Connect a minimum 1FF output capacitor between LDO_OUT and GND. Feedback. Feedback input for the DC-DC buck converter. Connect resistive divider from the 6 FB output to GND to adjust the output voltage. Maxim Integrated TOP VIEW WAD 16 ...
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... PGND connection. Do not use PGND as reference for sensitive feedback circuit. 20 RREF Signature Resistor Connection. Connect a 24.9kω resistor (R — EP Exposed Pad. Connect the exposed pad to GND. Maxim Integrated MAX5988A/MAX5988B Pin Description (continued) FUNCTION ). LED is connected isolation p-channel MOSFET. Connect a DD ...
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... The devices use the external 24.9kω resistor (R ) and the CLASS2 pin to set the classifi- SIG Maxim Integrated cation current at 10.5mA (Class 1, CLASS1 = GND) or 18mA (Class 2, CLASS2 = VDRV). The PSE uses this to determine the maximum power to deliver. The classifica- PD Interface ...
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... See the typical application circuit in CC and 4. The application circuit must ensure that the auxiliary power source can provide power to V Maxim Integrated means of external diodes. The voltage on V within the V ate. To allow operation of the DC-DC converter, the V and V edge, while on the falling edge the V down to 7 ...
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... Operation with Wall Adapter For applications where an auxiliary power source such as a wall power adapter is used to power the PD, the devices feature wall power adapter detection. The device Maxim Integrated MAX5988A/MAX5988B gives priority to the WAD supply over V smoothly switches the power supply to WAD when it is detected ...
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... RIPPLE(C) RIPPLE(ESR) Table 1. Design Selection Table OUTPUT (V) CERAMIC 3.3 2.2FF/100V 5 2.2FF/100V 12 2.2FF/100V Maxim Integrated where the output ripple due to output capacitance, ESR, and ESL is: × I OUT or whichever is larger. The peak-to-peak inductor current (I ). P-P S Use these equations for initial output capacitor selec- tion ...
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... PGND) and signal ground plane (connected to GND) separate. 3) Keep the high-current paths as short and wide as possible. Keep the path of switching current short Maxim Integrated PCB Layout and minimize the loop area formed by LX, the output capacitors, and the input capacitors. 4) Connect V copper area to help cool the IC to further improve efficiency and long-term reliability ...
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... IEEE 802.3af-Compliant, High-Efficiency, Class 1/Class 2, Powered Devices with Integrated DC-DC Converter RJ45 AND BRIDGE RECTIFIER TO µP OPEN-DRAIN OUTPUTS OR PULLDOWN SWITCHES TO 5V OUTPUTS Figure 3. MAX5988A/MAX5988B Buck Regulator and Fixed LDO Output Maxim Integrated C1 2.2µF 68nF VDRV CLASS2 C3 MPS 1µF LDO_FB WK MAX5988A ...
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... IEEE 802.3af-Compliant, High-Efficiency, Class 1/Class 2, Powered Devices with Integrated DC-DC Converter RJ45 AND BRIDGE RECTIFIER TO µP OPEN-DRAIN OUTPUTS OR PULLDOWN SWITCHES TO 5V OUTPUTS Figure 4. MAX5988A/MAX5988B Buck Regulator and Adjustable LDO Output Maxim Integrated Typical Application Circuits (continued) C1 2.2µF 68nF VDRV CLASS2 ...
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... IEEE 802.3af-Compliant, High-Efficiency, Class 1/Class 2, Powered Devices with Integrated DC-DC Converter V DD TVS GND RREF 5V 5V REGULATOR LDO_IN LDO_OUT LDO_FB CLASS2 CLASS MPS Maxim Integrated MAX5988A MAX5988B 5V DETECTION CLASSIFICATION 5V 1. CLK BANDGAP CONTROL V REF VREF LDO MPS LOGIC MAX5988A/MAX5988B Functional Diagram ...
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... TQFN-EP* MAX5988BETP+ 20 TQFN-EP* +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Maxim Integrated MAX5988A/MAX5988B For the latest package outline information and land patterns (foot- prints www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status ...
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... Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed ...