NCP1082

http://onsemi.com

7

Recommended Operating Conditions

Operating conditions define the limits for functional operation and parametric characteristics of the device. Note that the

functionality of the device outside the operating conditions described in this section is not warranted. Operating outside the

recommended operating conditions for extended periods of time may affect device reliability.

All values concerning the DC−DC controller, VDDH and VDDL blocks are with respect to ARTN. All others are with respect

Table 3. Operating Conditions

Symbol

Parameter

Min.

Typ.

Max.

Units

Conditions

INPUT SUPPLY

VPORT

Input supply voltage

0

57

V

VPORT = VPORTP −

SIGNATURE DETECTION

Vsignature

Input supply voltage signature detection range

1.4

9.5

V

Rsignature

Signature resistance (Note 4)

23.75

26.25

kW

Offset_current

I_VportP + I_Rtn

−

1.8

5

mA

VPORTP = RTN = 1.4 V

Sleep_current

I_VportP + I_Rtn

−

15

25

mA

VPORTP = RTN = 9.5 V

CLASSIFICATION

Vcl

Input supply voltage classification range

13

20.5

V

Iclass0

Class 0: Rclass 10 kW (Note 5)

0

−

4

mA

Iclass0 = I_VportP + I_Rdet

Iclass1

Class 1: Rclass 130 W (Note 5)

9

−

12

mA

Iclass1 = I_VportP + I_Rdet

Iclass2

Class 2: Rclass 69.8 W (Note 5)

17

−

20

mA

Iclass2 = I_VportP + I_Rdet

Iclass3

Class 3: Rclass 44.2 W (Note 5)

26

−

30

mA

Iclass3 = I_VportP + I_Rdet

Iclass4

Class 4: Rclass 30.9 W (Note 5)

36

−

44

mA

Iclass4 = I_VportP + I_Rdet

Internal current consumption during

classification (Note 6)

−

600

−

mA

For information only

UVLO

Vuvlo_on

Default turn on voltage (VportP rising)

38

40

V

UVLO pin tied to

Vuvlo_off

Default turn off voltage (VportP falling)

29.5

32

−

V

UVLO pin tied to

Vhyst_int

UVLO internal hysteresis

−

6

−

V

UVLO pin tied to

Vuvlo_pr

UVLO external programming range

13

−

50

V

UVLO pin connected to the

resistor divider (R1 & R2)

For information only

Vuvlo_pr_aux

UVLO external programming VPORT range

with low auxiliary supply support

8.5

−

18

V

UVLO & AUX pins configured

for auxiliary supply support

Vhyst_ext

UVLO external hysteresis

−

15

−

%

UVLO pin connected to the

resistor divider (R1 & R2)

Uvlo_Filter

UVLO on/off filter time

−

90

−

mS

For information only

AUXILIARY SUPPLY OPERATION – INPUT SUPPLY

Vaux_min1

VPORTP−ARTN voltage at startup

(required for VDDH > VDDH_Por_R)

8.7

−

−

V

VAUX rising − No external

load on VDDL & VDDH

Vaux_min2

VPORTP−ARTN voltage during PWM opera-

tion (required for VDDH > VDDH_Por_F)

8.5

−

−

V

Voltage with respect to

Ivddl_load1 & Ivddh_load1

for the load current conditions

4. Test done according to the IEEE 802.3af 2 Point Measurement. The minimum probe voltages measured at the PoE−PD are 1.4 V and 2.4 V,

and the maximum probe voltages are 8.5 V and 9.5 V.

6. This typical current excludes the current in the Rclass and Rdet external resistors.