LTC4270/LTC4271
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 3 & 4)
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
V
Overcurrent Sense Voltage
V
– V ,
CUT
SENSEn EE
l
l
hpen = 0Fh, cutn = D4h
89
152
94
159
99
168
mV
mV
hpen = 0Fh, cutn = E2h (Note 12)
l
l
l
l
Overcurrent Sense in AUTO Pin Mode
Class 0, Class 3
Class 1
89
26
94
28
99
30
mV
mV
mV
mV
Class 2
49
52
55
Class 4
152
159
168
V
Active Current Limit in 802.3af Compliant Mode
Active Current Limit in High Power Mode
V
EE
AGND – V
– V , hpen = 0Fh, limn = 80h
SENSEn EE
LIM
l
l
V
< V
< AGND – 29V
OUT
102
25
106
112
50
mV
mV
= 0V (Note 12)
OUT
hpen = 0Fh, limn = C0h
l
l
l
V
V
– V = 0 – 10V
204
102
25
212
106
225
115
50
mV
mV
mV
OUT
EE
AGND – V
EE
+ 23V < V
< AGND – 29V
OUT
= 0V (Note 12)
OUT
Active Current Limit in AUTO Pin Mode
V
< V
< AGND – 10V
OUT
EE
l
l
Class 0 to Class 3
Class 4
102
204
106
212
112
225
mV
mV
l
l
V
V
DC Disconnect Sense Voltage
Short-Circuit Sense
V
V
– V , rdis Bit = 0
2.6
1.3
3.8
1.9
4.9
mV
mV
MIN
SENSE
SENSE
EE
– V , rdis Bit = 1 (Note 12)
2.45
EE
l
l
V
– V – V , rdis Bit = 0
125
70
200
100
255
135
mV
mV
SC
SENSEn
EE
LIM
rdis bit = 1 (Note 12)
Port Current Readback
Resolution
No Missing Codes
12
Bits
LSB Weight
V
– V
30.518
25.1
μV/LSB
SENSEn
EE
Conversion Period
ms/
Convert
Port Voltage Readback
Resolution
No Missing Codes
– V
12
Bits
LSB Weight
V
5.8250
mV/LSB
SENSEn
EE
LTC4270 Die Temperature
Die Temperature Offset
Die Temperature LSB Weight
Digital Interface
Temperature Register = 00h (Note 7)
(Note 7)
–40
0.7
°C
°C/LSB
l
l
V
ILD
V
IHD
Digital Input Low Voltage
Digital Input High Voltage
Digital Output Voltage Low
(Note 6)
(Note 6)
0.8
V
V
2.2
l
l
I
I
= 3mA, I = 3mA
0.4
0.7
V
V
SDAOUT
SDAOUT
INT
= 5mA, I = 5mA
INT
l
l
Internal Pull Up to V
ADn, RESET, MSD, INT, GPn
50
50
kΩ
kΩ
DD
Internal Pull Down To DGND
AUTO, MID
42701f
5
Linear [ Linear ]
