LTC4257-1 Linear Technology, LTC4257-1 Datasheet - Page 2

• Manufacturer Part Number: LTC4257-1
• Description: Power over Ethernet Interface Controller with Dual Current Limit
• Manufacturer: Linear Technology

ELECTRICAL CHARACTERISTICS
ABSOLUTE AXI U RATI GS
LTC4257-1
(Notes 1, 2)
V
V
PWRGD Voltage ...................... V
R
PWRGD Current .................................................. 10mA
R
PACKAGE/ORDER I FOR ATIO
Consult LTC Marketing for parts specified with wider operating temperature ranges.
temperature range, otherwise specifications are at T
SYMBOL
V
I
I
R
R
V
V
2
IN_ON
IN_CLASS
IN
I
SIGNATURE
INVALID
IH
IL
IN
OUT
CLASS
CLASS
CLASS
R
CLASS
Voltage ............................................. 0.3V to – 100V
, SIGDISA,
V
NC
NC
IN
T
JMAX
Voltage ............................ V
Current .................................................. 100mA
1
2
3
4
8-LEAD PLASTIC SO
= 150 C,
S8 PACKAGE
TOP VIEW
PARAMETER
Supply Voltage
IC Supply Current when ON
IC Supply Current During Classification V
Current Accuracy During Classification 10mA < I
Signature Resistance
Invalid Signature Resistance
Signature Disable
Signature Disable
Maximum Operating Voltage
Signature Range
Classification Range
UVLO Turn-On Voltage
UVLO Turn-Off Voltage
High Level Input Voltage
Low Level Input Voltage
JA
W
= 150 C/W
8
7
6
5
GND
SIGDISA
PWRGD
V
OUT
W W
U
IN
+ 100V to V
IN
S8 PART MARKING
+ 7V to V
LTC4257CS8-1
LTC4257IS8-1
ORDER PART
W
NUMBER
42571
4257I1
U
CONDITIONS
Voltage with Respect to GND Pin (Notes 4, 5, 6)
V
(Note 7)
(Notes 8, 9)
–1.5V V
IEEE 802.3af 2-Point Measurement (Notes 4, 5)
– 1.5V V
Tied to GND, IEEE 802.3af 2-Point Measurement
(Notes 4, 5)
With Respect to V
High Level Invalidates Signature (Note 10)
With Respect to V
Low Level Enables Signature
IN
IN
A
= 25 C. (Note 3)
= – 48V, Pins 5, 6, 7 Floating
= – 17.5V, Pins 2, 7 Floating, V
IN
IN
– 0.3V
– 0.3V
The
CLASS
IN
IN
U
–9.5V, V
– 9.5V, SIGDISA and V
< 40mA, – 12.5V V
denotes the specifications which apply over the full operating
IN
IN
,
,
Operating Ambient Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 10 sec).................. 300 C
OUT
R
CLASS
LTC4257C-1 ............................................ 0 C to 70 C
LTC4257I-1 ......................................... –40 C to 85 C
S8 Package ....................................... – 65 C to 150 C
DD Package ...................................... – 65 C to 125 C
ELECTRICALLY ISOLATED PCB HEATSINK
8-LEAD (3mm 3mm) PLASTIC DFN
V
NC
NC
EXPOSED PAD TO BE SOLDERED TO
Tied to GND,
IN
T
JMAX
1
2
3
4
OUT
= 125 C,
DD PACKAGE
IN
TOP VIEW
OUT
Tied to GND
– 21V,
JA
= 43 C/W
8
7
6
5
GND
SIGDISA
PWRGD
V
OUT
– 12.5
– 34.8
– 29.3
23.25
– 1.5
0.35
MIN
3
DD PART MARKING
–36.0
–30.5
LTC4257CDD-1
LTC4257IDD-1
0.50
ORDER PART
TYP
9
NUMBER
LBFZ
– 37.2
– 31.5
26.00
MAX
– 9.5
0.65
11.8
0.45
– 57
– 21
57
3.5
3
UNITS
42571fa
mA
mA
k
k
%
V
V
V
V
V
V
V