lm5072mhx-80 National Semiconductor Corporation, lm5072mhx-80 Datasheet - Page 3

• Manufacturer Part Number: lm5072mhx-80
• Description: Integrated 100v Power Over Ethernet Pd Interface And Pwm Controller With Aux Support
• Manufacturer: National Semiconductor Corporation

Pin Number
Pin Descriptions
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
ICL_FAUX
nPGOOD
RCLASS
COMP
Name
DCCL
RAUX
ARTN
VEE
RTN
OUT
VCC
VIN
RT
SS
CS
EP
FB
PWM controller oscillator frequency programming pin.
Soft-start programming pin.
Positive supply pin for the PD interface and the internal PWM controller start-up regulator.
PD classification programming pin.
Inrush current limit programming pin; also the front auxiliary power enable pin.
PD interface DC current limit programming pin.
Negative supply pin for PD interface; connected to PoE and/or front auxiliary power return path.
PWM controller power return; connected to the drain of the internal PD interface hot swap
MOSFET; should be externally connected to the reference ground of the PWM controller.
PWM controller gate driver output pin.
PWM controller start-up regulator output pin.
PD interface Power Good indicator and delay timer pin; active low state indicates PoE interface
is in normal operation.
PWM controller current sense input pin.
Rear auxiliary power enable pin; can be programmed for auxiliary power dominance over PoE
power.
PWM controller voltage feedback pin and inverting input of the internal error amplifier; connect
to ARTN to disable the error amplifier in isolated dc-dc converter applications.
Output of the internal error amplifier and control input to the PWM comparator. In isolated
applications, COMP is controlled by the secondary side error amplifier via an opto-coupler.
PWM controller reference ground pin; should be shorted externally to the RTN pin as a single
point ground connection to improve noise immunity.
Exposed metal pad on the underside of the device. It is recommended to connect this pad to a
PC Board plane connected to the VEE pin to improve heat dissipation.
3
Description
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