MAX5971BETI+ Maxim Integrated Products, MAX5971BETI+ Datasheet - Page 14

• Manufacturer Part Number: MAX5971BETI+
• Description: Hot Swap & Power Distribution IEEE 802.3af/at PSE Controller
• Manufacturer: Maxim Integrated Products

Specifications of MAX5971BETI+

• Lead Free Status / Rohs Status: Details

Single-Port, 40W, IEEE 802.3af/at,
PSE Controller with I
The MAX5971B is a single-port power controller designed
for use in IEEE 802.3af/802.3at-compliant PSE. This
device provides PD discovery, classification, current
limit, and DC and AC load-disconnect detections. The
MAX5971B supports both fully automatic operation and
software programmability, and features an integrated
power MOSFET and sense resistor. The device also sup-
ports new Class 5 and 2-event classification for detection
and classification of high-power PDs. The MAX5971B
provides up to 40W to a single port (Class 5 enabled), and
still provides high-capacitance detection for legacy PDs.
The MAX5971B features an I
interface, and is fully software configurable and pro-
grammable. The device provides instantaneous readout
14
MIDSPAN
_____________________________________________________________________________________
LEGACY
AGND
LED
INT
V
EN
EE
ADO
INTERFACE (SPI)
BIAS AND
MONITOR
REGISTER FILE
ANALOG
SUPPLY
SERIAL PORT
SCL
Detailed Description
CENTRAL LOGIC
SDA
UNIT (CLU)
INTERNAL
SUPPLIES
VOLTAGE
REFERENCES
CURRENT
REFERENCES
2
C-compatible, 2-wire serial
MACHINE (SM)
PORT STATE
PWM
OSC STATUS
MONITOR
PWMEN
OSC
AC DISCONNECT
SIGNAL (ACD)
2
GENERATOR
TRIANGLE
WAVE
C
MAX5971B
of port current through the I
provides input undervoltage lockout (UVLO), input under-
voltage detection, input overvoltage lockout, overtem-
perature protection, output voltage slew-rate limit dur-
ing startup, and LED status indication. The MAX5971B
programmability includes startup timeout, overcurrent
timeout, and load-disconnect detection timeout.
The MAX5971B is reset by any of the following conditions:
1) Power-Up. Reset condition is cleared once V
2) Hardware Reset. Reset occurs once the EN input is
CLASSIFICATION
DETECTION AND
CURRENT-LIMIT
PROBING AND
above the UVLO threshold.
driven low (> 40Fs, typ) any time after power-up. The
device exits the reset condition once the EN input is
driven high again.
CONTROL
VOLTAGE
CONTROL
THRESHOLD
SETTINGS
AC DETECTOR
A = 1
ACD
REFERENCE
CURRENT
POWER ENABLE
OVERCURRENT, AND OPEN-
CLASS 5 ENABLE/DISABLE,
AND FOLDBACK CONTROL
CURRENT-LIMIT CONTROL
OVERCURRENT AND
CIRCUIT SENSING,
9-BIT ADC
CURRENT-LIMIT,
AC DISCONNECT
ILIM1
CURRENT SENSING
ENABLE
Simplified Diagram
CONTROL
2
GATE-
DRIVE
ILIM2
C interface. The MAX5971B
VOLTAGE
SENSING
FOLDBACK
CONTROL
INTERNAL
INTERNAL
MOSFET
R
SENSE
AGND
EE
Reset
DET
OUTP
OUT
rises