MAX5945 MAXIM [Maxim Integrated Products], MAX5945 Datasheet
MAX5945
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MAX5945 Summary of contents
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... PD disconnect AC detection threshold, and PD disconnect detection timeout. The MAX5945 is available in a 36-pin SSOP package and is rated for both extended (-40°C to +85°C) and commercial (0°C to +70°C) temperature ranges. Power-Sourcing Equipment (PSE) ...
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... Maximum Power Dissipation 36-Pin SSOP (derate 11.4mW/°C above +70°C) .........941mW Operating Temperature Ranges: MAX5945EAX ..................................................-40°C to +85°C MAX5945CAX .....................................................0°C to +70°C Storage Temperature Range .............................-65°C to +150°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C . Driving GATE_ higher than 11.4V above DGND = +3 ...
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ELECTRICAL CHARACTERISTICS (continued) (AGND = +32V to +60V 0V values are at AGND = +48V, DGND = +48V, V negative otherwise.) PARAMETER SYMBOL Minimum Foldback Current- V TH_FB Limit Threshold SENSE_ Input Bias Current SUPPLY ...
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Quad Network Power Controller for Power-Over-LAN ELECTRICAL CHARACTERISTICS (continued) (AGND = +32V to +60V 0V values are at AGND = +48V, DGND = +48V, V negative otherwise.) PARAMETER SYMBOL AC Load Disconnect I ACTH Threshold ...
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ELECTRICAL CHARACTERISTICS (continued) (AGND = +32V to +60V 0V values are at AGND = +48V, DGND = +48V, V negative otherwise.) PARAMETER SYMBOL Internal Input Pullup/Pulldown R DIN Resistor Open-Drain Output Low V OL Voltage ...
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Quad Network Power Controller for Power-Over-LAN ELECTRICAL CHARACTERISTICS (continued) (AGND = +32V to +60V 0V values are at AGND = +48V, DGND = +48V, V negative otherwise.) PARAMETER SYMBOL Setup Time for a Repeated t ...
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AUTO = AGND = DGND = 0V, RESET = SHD_ = unconnected -48V +25°C, unless otherwise noted.) A DIGITAL SUPPLY CURRENT vs. INPUT VOLTAGE 6 MEASURED ...
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... SENSE = 240Ω TO 57Ω) MAX5945 toc13 (AGND - OUT) 20V/div 0V GATE 10V/div V EE INT 2V/div 0V 400µs/div MAX5945 toc15 (AGND - OUT) 20V/div 0V I OUT 5A/div 0A GATE 10V/div V EE 4µs/div MAX5945 toc17 (AGND - OUT) 20V/div ...
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... OUT) 5V/div 0V I OUT 1mA/div 0A = 0.5Ω, all registers = default setting, SENSE MAX5945 toc19 (AGND - OUT) 20V/div 0V I OUT 100mA/div GATE_ V EE 100ms/div MAX5945 toc21 (AGND - OUT) 5V/div 0V I OUT 1mA/div 0A 100ms/div MAX5945 toc23 (AGND - OUT) 20V/div 0V I OUT 100mA/div 0A GATE_ 10V/div V ...
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... OUT 2mA/div GATE_ 10V/div 0V = 0.5Ω, all registers = default setting, SENSE MAX5945 toc25 (AGND - OUT) 5V/div 0V I OUT 1mA/div 0A GATE_ 10V/div V EE MAX5945 toc27 (AGND - OUT) 5V/div 0V I OUT 1mA/div 0A GATE_ 10V/div V EE MAX5945 toc29 (AGND - OUT) 5V/div CLASS4 CLASS3 CLASS2 CLASS1 ...
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... EE capacitor between AGND and V AUTO or SHUTDOWN Mode Input. Force high to enter AUTO mode after a reset or power-up. Drive low to put the MAX5945 into SHUTDOWN mode. In SHUTDOWN mode, software controls the 35 AUTO operational modes of the MAX5945. A 50kΩ internal pulldown resistor defaults AUTO low. AUTO latches when V Software commands can take the MAX5945 out of AUTO while AUTO is high ...
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... CURRENT LIMIT (ILIM) OPEN CIRCUIT (OC) OVERCURRENT 4mV ant PSE. The MAX5945 can be used in either endpoint PSE (LAN switch/router) or midspan PSE (power injec- tor) applications. The MAX5945 is fully software-configurable and pro- grammable with more than 25 internal registers. The device features an I face and a class-overcurrent detection. The class-over- ...
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... Software reset. Writing a 1 into R1Ah[4] any time after power-up. • Thermal shutdown. During a reset, the MAX5945 resets its register map to the reset state as shown in Table 30 and latches in the state of AUTO (pin 35) and MIDSPAN (pin 2). During normal operation, changes at the AUTO and MIDSPAN inputs are ignored ...
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... IEEE 802.3af specification for a PSE detect- ing a valid PD signature (see the Typical Application MANUAL Mode Circuit and Figure 2). The MAX5945 can probe and cat- egorize different types of devices connected to the port such as a valid PD, an open circuit, a low resistive load, a high resistive load, a high capacitive load, a positive DC supply negative DC supply ...
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... L, RESET_IC = H, V The MAX5945 always checks the status of all ports before turning off. A priority logic system determines the order to prevent the simultaneous turn-on or turn-off of the ports. ...
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... FAULT After power-off due to an overcurrent fault, and if the RSTR_EN bit is set, the t reset but starts decrementing at the same slower pace. The MAX5945 allows the port to be powered on only when the t FAULT automatic duty-cycle protection to the external MOSFET to avoid overheating. The duty cycle is programmable using R16h[6-7] ...
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... The MAX5945 also features +1.35V DDUVLO MAX5945 in reset and the ports shut off. Bit 0 in the supply event register shows the status of V (Table 11) after V outputs reference to DGND. DGND and AGND are completely isolated internally to the MAX5945 ...
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... SCL if there are multiple masters the master in a single-master system has an open-drain SCL output. of greater DD Each transmission consists of a START condition (Figure 7) sent by a master, followed by the MAX5945 7-bit slave address plus R/W bit, a register address byte, one or more data bytes, and finally a STOP condition ...
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SDAIN t SU, DAT t LOW SCL t HIGH t HD, STA t R START CONDITION Figure 5. 2-Wire Serial Interface Timing Details SDAIN/SDA t LOW SCL t HIGH t HD, STA t R START CONDITION Figure 6. 3-Wire Serial ...
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... Bit Transfer and A0 latch in upon the reset of the MAX5945 into reg- ister R11h. The MAX5945 monitors the bus continuous- ly, waiting for a START condition followed by the MAX5945’s slave address. When the MAX5945 recog- Acknowledge nizes its slave address, it acknowledges and is then ready for continued communication ...
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... The first byte of information is the command byte (Figure 11). The command byte determines which register of the MAX5945 is written to by the next byte, if received. If the MAX5945 detects a STOP condition after receiving the command byte, then the MAX5945 takes no further action beyond storing the command byte ...
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... Thus, a read is initiated by first configuring the MAX5945’s command byte by performing a write (Figure 12). The master now reads ‘n’ consecutive bytes from the MAX5945, with the first data byte read from the register addressed by the initialized command byte (Figure 13). When performing read-after-write veri- fication, remember to reset the command byte’ ...
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Table 5. Interrupt Register ADDRESS = 00h SYMBOL BIT R/W Interrupt signal for supply faults. SUP_FLT is the logic OR of all the bits [7:0] in register R0Ah/R0Bh SUP_FLT 7 R (Table 8). Interrupt signal for startup failures. TSRT_FLT is ...
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Quad Network Power Controller for Power-Over-LAN Table 7. Power Event Register ADDRESS = 02h 03h SYMBOL BIT R/W R/W PG_CHG4 7 R CoR PG_CHG3 6 R CoR PG_CHG2 5 R CoR PG_CHG1 4 R CoR PWEN_CHG4 3 R CoR PWEN_CHG3 ...
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... When read through the CoR CLASS_[0] R09h address, the register content will be cleared. A Reserved reset sets R08h/R09h = 00h. DET_[2] The MAX5945 continuously monitors the power supplies DET_[1] and sets the appropriate bits in the supply event register (Table 11). V DET_[0] V exceeds its overvoltage threshold ...
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... MIDSPAN and AUTO inputs. Changes to those inputs during nor- mal operation are ignored. The MAX5945 uses two bits for each port to set the mode of operation (Table 15). Set the modes according to Table 15a. A reset sets R12h = AAAAAAAA where A represents the latched-in state of the AUTO input prior to the reset ...
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Table 13. Power Status Register ADDRESS = 10h SYMBOL BIT R/W PGOOD4 7 R Power-good condition on port 4 PGOOD3 6 R Power-good condition on port 3 PGOOD2 5 R Power-good condition on port 2 PGOOD1 4 R Power-good condition ...
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Quad Network Power Controller for Power-Over-LAN In MANUAL mode, R14h works like a pushbutton. Set the bits high to begin the corresponding routine. The bit clears after the routine finishes. When entering AUTO mode, R14h defaults to FFh. When entering ...
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... FAULT ther extend the programming range of these timers and also increase the programming resolution. When the MAX5945 shuts down a port due to an extended overcurrent condition (either during startup or normal operation), if RSRT_EN is set high, then the part does not allow the port to power back on before the restart timer (Table 19a) returns to zero ...
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... After execution, the bits reset to 0. During detection or classification, if PWR_ON_ 30 ______________________________________________________________________________________ DESCRIPTION ) according to port FLT_LIM DESCRIPTION DESCRIPTION goes high, the MAX5945 gracefully terminates the cur- rent operation and turn-on power to the port. The MAX5945 ignores the PWR_ON_ in AUTO mode. A reset sets R19h = 00h. ...
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... R ID_CODE[ REV [2] REV 1 R REV [ REV [0] ID register keeps track of the device ID number and revision. The MAX5945’s ID_CODE[4:0] = 11000b. Contact the factory for REV[2:0] value. Table 24. SMODE Register ADDRESS = 1Ch SYMBOL BIT CoR Reserved 7 — Reserved Reserved 6 — ...
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Quad Network Power Controller for Power-Over-LAN Table 25. Watchdog Timer Register ADDRESS = 1Eh SYMBOL BIT R/W 7 R/W WDTIME[7] 6 R/W WDTIME[6] 5 R/W WDTIME[5] 4 R/W WDTIME[4] WDTIME 3 R/W WDTIME[3] 2 R/W WDTIME[2] 1 R/W WDTIME[1] 0 ...
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Table 27. Program Register 1 ADDRESS = 23h SYMBOL BIT R/W 7 R/W IGATE[2] IGATE 6 R/W IGATE[1] 5 R/W IGATE[0] DET_BYP 4 R/W Detect bypass protection in AUTO mode OSCF_RS 3 R/W OSC_FAIL Reset Bit 2 R/W AC_TH[2] AC_TH ...
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Quad Network Power Controller for Power-Over-LAN Table 29. Program Register 3 ADDRESS = 28h SYMBOL BIT R TF_PR[3 TF_PR[2]. t TF_PR 5 R TF_PR[1 TF_PR[0 TS_PR[3 ...
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Quad Network Power Controller ______________________________________________________________________________________ for Power-Over-LAN 35 ...
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Quad Network Power Controller for Power-Over-LAN 36 ______________________________________________________________________________________ ...
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... PSE (SWITCHES/ROUTERS, ETC) DATA PHY POWER MAX5020 3.3V MAX5945 -48V TO +3.3V DC-DC CONTROLLER GND -48V Figure 14. PoE System Block Diagram ______________________________________________________________________________________ Quad Network Power Controller for Power-Over-LAN PD (IP PHONE, WIRELESS ACCESS POINT, SECURITY CAMERAS, ETC.) RJ–45 RJ–45 POWER AND DATA OVER TWISTED-PAIR POWER ETHERNET CABLE ...
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... TD1+ 19 TX1- 5 TD1- -48VOUT 0.1µF 75Ω 23 RXT1 1000pF 250VAC 0.1µF 75Ω 20 TXCT1 -48VRTN V DD 3kΩ SDAOUT 3kΩ SDAIN MAX5945 HPCL063L 3kΩ SCL HPCL063L DGND 0.5Ω 1% -48V FDT3612 100V, 120mΩ SOT-223 CHANNELS RJ–45 CONNECTOR 0.1µF 75Ω 0.1µF 75Ω ...
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... SCL OPTIONAL BUFFER Figure 16. PoE System Diagram of One Complete Port, Midspan PSE ______________________________________________________________________________________ Quad Network Power Controller for Power-Over-LAN -48VRTN V DD 3kΩ SDAOUT 3kΩ SDAIN MAX5945 HPCL063L 3kΩ SCL HPCL063L DGND 0.5Ω 1% -48V FDT3612 100V, 120mΩ SOT-223 CHANNELS RJ–45 ...
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Quad Network Power Controller for Power-Over-LAN R10 2Ω R6 1Ω C3 15nF Q4 MMBTA56 GND GND 1 MAX5020 0.47µF 4 100V SS_SHDN C2 0.022µF -48V -48V Figure 17. -48V to +3.3V (300mA) Boost ...
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Component List DESIGNATION DESCRIPTION C1 0.1µF, 25V ceramic capacitor C2 0.022µF, 25V ceramic capacitor C3 15nF, 25V ceramic capacitor 220µF capacitor C4 Sanyo 6SVPA220MAA C5 4.7µF, 16V ceramic capacitor C6 0.1µF, 100V ceramic capacitor C7 0.22µF, 16V ceramic capacitor C8 ...
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... NOTE: ALL SIGNAL PINS ARE REFERENCED TO DGND. DGND RANGE IS BETWEEN V Typical Operating Circuit 1 (without AC Load Removal Detection) 42 ______________________________________________________________________________________ -48VRTN 1.8V TO 3.7V, (REF TO DGND 180Ω 3kΩ SDAOUT 3kΩ SDAIN MAX5945 HPCL063L 3kΩ SCL HPCL063L DGND 0.5Ω 1% -48V AND (AGND + 4V). EE Typical Operating Circuits -48V RTN OUTPUT TO PORT V DD 1kΩ ...
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... FOR AC DISCONNECT DETECTION CIRCUIT TO OPERATE. Typical Operating Circuit 2 (with AC Load Removal Detection) ______________________________________________________________________________________ Quad Network Power Controller for Power-Over-LAN Typical Operating Circuits (continued) -48VRTN V DD 3kΩ SDAOUT 3kΩ SDAIN MAX5945 HPCL063L 3kΩ SCL HPCL063L DGND 0.5Ω 1% -48V FDT3612 100V, 120mΩ SOT-223 CHANNELS ...
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Quad Network Power Controller for Power-Over-LAN (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages TOP VIEW FRONT VIEW Maxim cannot ...