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Electrical characteristics (continued) – Rainbow Electronics MAX5969B User Manual

Page 4

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IEEE 802.3af/at-Compliant, Powered Device Interface

Controllers with

Integrated Power MOSFET

MAX5969A/MAX5969B

4 ______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

IN

= (V

DD

- V

SS

) = 48V, R

DET

= 24.9kω, R

CLS

= 615ω. RTN, WAD, PG, and 2EC unconnected, all voltages are referenced to V

SS,

unless otherwise noted. T

A

= T

J

= -40

N

C to +85

N

C, unless otherwise noted. Typical values are at T

A

= +25

N

C.) (Note 3)

Note 3: All devices are 100% production tested at T

A

= +25NC. Limits over temperature are guaranteed by design.

Note 4: The input offset current is illustrated in Figure 1.
Note 5: Effective differential input resistance is defined as the differential resistance between V

DD

and V

SS

. See Figure 1.

Note 6: Classification current is turned off whenever the device is in power mode.
Note 7: UVLO hysteresis is guaranteed by design, not production tested.
Note 8: A 20V glitch on input voltage that takes V

DD

below V

ON

shorter than or equal to t

OFF_DLY

does not cause the MAX5969A/

MAX5969B to exit power-on mode.

Note 9: In power mode, current-limit foldback is used to reduce the power dissipation in the isolation MOSFET during an overload

condition across V

DD

and RTN.

Figure 1. Effective Differential Input Resistance/Offset Current

I

IN

I

INi + 1

I

INi

I

OFFSET

dR

i

1V

V

INi

V

INi + 1

I

OFFSET

x I

INi

-

V

INi

dR

i

dR

i

x

(V

INi + 1

- V

INi

)

=

1V

(I

INi + 1

- I

INi

)

(I

INi + 1

- I

INi

)

V

IN