MAX5984 MAXIM [Maxim Integrated Products], MAX5984 Datasheet - Page 12

• Manufacturer Part Number: MAX5984
• Description: Single-Port, 40W, IEEE 802.3af/at PSE Controller with Integrated MOSFET
• Manufacturer: MAXIM [Maxim Integrated Products]

Single-Port, 40W, IEEE 802.3af/802.3at PSE
Controller with Integrated MOSFET
12
8–11, 15
16, 18,
20, 22,
24, 28
26, 27
PIN
12
13
14
17
19
21
23
25
—
_____________________________________________________________________________________
7
MIDSPAN
LEGACY
V
NAME
AGND
OUTP
EE_DIG
OSC
OUT
N.C.
LED
DET
I.C.
EN
EP
Detection Collision Avoidance Logic Input. Referenced to V
to the digital supply. Leave unconnected to activate the detection collision avoidance circuitry
for midspan PSE systems. Force low to disable this function for an end-point PSE system. The
MIDSPAN logic level latches after the device is powered up or after a reset condition.
Internally Connected. Connect I.C. to V
Digital Low-Side Supply Input. Connect to V
Legacy Detection Logic Input. Referenced to V
supply. Leave unconnected to activate the legacy PD detection. Force low to disable this function.
The LEGACY logic level latches after the device is powered up or after a reset condition.
Enable Input. Referenced to V
unconnected to enable the device. Force low for at least 40Fs to reset the device. The MIDSPAN,
OSC, and LEGACY states latch-in when the reset condition is removed (low-to-high transition).
No Connection. Not internally connected. Leave N.C. unconnected.
LED Indicator Open-Drain Output. Referenced to V
external LED directly. Blinking functionality is provided to signal different conditions (see the PWM
and LED Signals section). Connect LED to AGND externally or to an external supply (if available)
through a series resistance (Figures 6 and 7).
AC Disconnect Triangular Wave Output. Bypass with a 100nF (Q10% tolerance) external capacitor
to V
function and to activate the DC disconnect function. The OSC state latches after the device is
powered up or after a reset condition.
High-Side Supply Input
Detection/Classification Voltage Output. DET is used to set the detection mark event and
classification probe voltages and for the AC current sensing when using the AC disconnect
function. To use the AC disconnect function, place a 1kI and 0.47FF RC series in parallel with the
external protection diode to OUTP (Figure 7).
Port Pullup Output. OUTP is used to pull up the port voltage to AGND when needed. If AC
disconnect is used, connect OUTP to the anode of the AC-blocking diode. If AC disconnect is
not used, connect OUTP to OUT (Figures 6 and 8). Bypass OUTP to AGND with a 100V, 0.1FF
ceramic capacitor.
Integrated MOSFET Output. If DC disconnect is used, connect the port output to OUTP (Figures
6 and 8). If the AC disconnect function is used, connect OUT to the cathode of the AC-blocking
diode (Figure 7).
Exposed Pad. Connect EP to V
EE
to enable the AC disconnect function. Connect OSC to V
EE
EE
. EN is internally pulled up to the digital supply. Leave
externally. See the Layout Procedure section for details.
EE
.
FUNCTION
EE
externally.
EE
. LEGACY is internally pulled up to the digital
EE
Pin Description (continued)
. LED can sink 10mA and can drive an
EE
. MIDSPAN is internally pulled up
EE
to disable the AC disconnect