ltc4266a Linear Technology Corporation, ltc4266a Datasheet - Page 8

• Manufacturer Part Number: ltc4266a
• Description: Quad Poe/poe+/ltpoe++ Pse Controller
• Manufacturer: Linear Technology Corporation

LTC4266A/LTC4266C
8
TYPICAL PERFORMANCE CHARACTERISTICS
900
800
700
600
500
400
300
200
100
0
–54
Current Limit Foldback
–45
–36
108.00
107.25
106.50
105.75
105.00
95.25
93.00
96.00
94.50
93.75
V
OUTn
–40
–40
–27
802.3af I
vs Temperature
802.3af I
vs Temperature
V
V
R
REG 47h = D4h
PORT 1
V
V
R
REG 48h = 80h
PORT 1
(V)
DD
EE
SENSE
DD
EE
SENSE
= –54V
= –54V
= 3.3V
= 3.3V
V
V
R
REG 48h = C0h
–18
DD
EE
SENSE
= 0.25Ω
= 0.25Ω
0
= –54V
0
= 3.3V
LIM
CUT
TEMPERATURE (°C)
TEMPERATURE (°C)
= 0.25Ω
–9
4266AC G14
Threshold
Threshold
40
40
0
225
200
175
150
125
100
75
50
25
0
80
80
4266AC G12
4266AC G10
400
350
300
250
200
150
100
50
0
120
ADC Noise Histogram
Current Readback in Fast Mode
120
V
SENSEn
381
375
372
191
384
378
429
423
420
432
426
– V
192
EE
= 110.4mV
ADC OUTPUT
193
1.9375
1.8125
1.7500
2.0000
1.8750
162
158
163
161
160
159
194
–40
–40
802.3at I
vs Temperature
DC Disconnect Threshold
vs Temperature
V
V
R
REG 47h = E2h
PORT 1
V
V
R
REG 47h = E2h
PORT 1
DD
EE
DD
EE
SENSE
SENSE
195
= –54V
= –54V
= 3.3V
= 3.3V
= 0.25Ω
= 0.25Ω
4266AC G15
0
0
CUT
196
TEMPERATURE (°C)
TEMPERATURE (°C)
Threshold
40
40
–0.5
–1.0
1.0
0.5
0
CURRENT SENSE RESISTOR INPUT VOLTAGE (mV)
0
ADC Integral Nonlinearity
Current Readback in Fast Mode
50
80
80
100
4266AC G11
4266AC G13
150
120
120
200 250
7.75
7.00
636
8.00
7.50
7.25
652
648
644
640
630
300
350
400
4266AC G16
450
4266acfa
500