Datasheet
LTC4274A/LTC4274C
4
4274acfc
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Current Sense
V
CUT
Overcurrent Sense Voltage V
SENSE
– V
EE
, hpen = 01h, cut[5:0] ≥ 4 (Note 12)
cutrng = 0
cutrng = 1
l
l
9
4.5
9.38
4.69
9.75
4.88
mV/LSB
mV/LSB
Overcurrent Sense in AUTO Pin Mode Class 0, Class 3
Class 1
Class 2
Class 4
l
l
l
l
90
26
49
152
94
28
52
159
98
30
55
166
mV
mV
mV
mV
V
LIM
Active Current Limit in 802.3af
Compliant Mode
V
SENSE
– V
EE
, hpen = 01h, lim = 80h,
V
EE
= 55V (Note 12)
V
EE
< V
OUT
< AGND – 29V
AGND – V
OUT
= 0V
l
l
102
20
106 110
50
mV
mV
V
LIM
Active Current Limit in High Power Mode hpen = 01h, lim = C0h, V
EE
= 55V
V
OUT
– V
EE
= 0V to 10V
V
EE
+ 23V < V
OUT
< AGND – 29V
AGND – V
OUT
= 0V
l
l
l
204
100
20
212
106
221
113
50
mV
mV
mV
V
LIM
Active Current Limit in AUTO Pin Mode V
OUT
– V
EE
= 0V to 10V, V
EE
= 55V
Class 0 to Class 3
Class 4
l
l
102
204
106
212
110
221
mV
mV
V
MIN
DC Disconnect Sense Voltage V
SENSE
– V
EE
, rdis = 0
V
SENSE
– V
EE
, rdis = 1
l
l
2.6
1.3
3.8
1.9
4.8
2.41
mV
mV
V
SC
Short-Circuit Sense V
SENSE
– V
EE
– V
LIM
, rdis = 0
V
SENSE
– V
EE
– V
LIM
, rdis = 1
l
l
160
75
200
100
255
135
mV
mV
Port Current ReadBack
Resolution No Missing Codes, fast_iv = 0 14 Bits
LSB Weight V
SENSE
– V
EE
30.5 µV/LSB
50Hz to 60Hz Noise Rejection (Note 7) 30 dB
Port Voltage ReadBack
Resolution No Missing Codes, fast_iv = 0 14 bits
LSB Weight AGND – V
OUT
5.835 mV/LSB
50Hz to 60Hz Noise Rejection (Note 7) 30 dB
Digital Interface
V
ILD
Digital Input Low Voltage ADn, SHDN, RESET, MSD, AUTO, MID
(Note 6)
l
0.8 V
I
2
C Input Low Voltage SCL, SDAIN (Note 6)
l
0.8 V
V
IHD
Digital Input High Voltage (Note 6)
l
2.2 V
Digital Output Low Voltage I
SDAOUT
= 3mA, I
INT
= 3mA
I
SDAOUT
= 5mA, I
INT
= 5mA
l
l
0.4
0.7
V
V
Internal Pull-Up to V
DD
ADn, SHDN, RESET, MSD 50 k
Internal Pull-Down to DGND AUTO, MID 50 k
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. AGND – V
EE
= 54V, AGND = DGND, and V
DD
– DGND = 3.3V
unless otherwise noted. (Notes 3, 4)