Datasheet

LTC4290/LTC4271
8
429071fa
For more information www.linear.com/LTC4290
Classification Transient Response
to 40mA Load Step
typicAl perForMAnce chArActeristics
Powering Up into a 180µF Load Classification Current Compliance
V
DD
Supply Current vs Voltage V
EE
Supply Current vs Voltage
802.3af Power On Sequence in
AUTO Pin Mode
802.3at Power On Sequence in
AUTO Pin Mode
Power On Sequence with 10V
PP
60Hz Noise
FORCED CURRENT
DETECTION
VEE = –55V
CLASS 3 PD
VEE
50ms/DIV
–60
PORT VOLTAGE (V)
–10
–20
–30
–40
–50
0
429071 G01
FORCED VOLTAGE
DETECTION
802.3af
CLASSIFICATION
POWER ON
AGND
FORCED CURRENT
DETECTION
VEE = –55V
CLASS 4 PD
VEE
50ms/DIV
–60
PORT VOLTAGE (V)
–10
–20
–30
–40
–50
0
429071 G02
FORCED VOLTAGE
DETECTION
802.3at
CLASSIFICATION
POWER ON
AGND
AGND
50ms/DIV
–25
PORT VOLTAGE (V)
0
–5
–10
–15
–20
5
429071 G03
FORCED VOLTAGE
DETECTION
802.3af
CLASSIFICATION
POWER ON
PORT OFF
FORCED CURRENT
DETECTION
NORMAL DETECT
DETECT WITH 60Hz NOISE
5ms/DIV
429071 G04
FET ON
FOLDBACK
VEE = –54V
AGND
VEE
VEE
0mA
PORT VOLTAGE
20V/DIV
PORT CURRENT
200mA/DIV
GATE VOLTAGE
10V/DIV
425mA
CURRENT LIMIT
LOAD FULLY CHARGED
50µs/DIV
40mA
0mA
429071 G05
–20V
PORT
VOLTAGE
1V/DIV
PORT
CURRENT
20mA/DIV
V
DD
= 3.3V
V
EE
= –54V
CLASSIFICATION CURRENT (mA)
429071 G06
0 2010 30 40 50 60 70
0
–2
–4
–6
–8
–10
–12
–14
–16
–18
–20
CLASSIFICATION VOLTAGE (V)
V
DD
SUPPLY VOLTAGE (V)
429071 G07
2.7 2.92.8 3.0 3.1 3.2 3.3 3.4 3.63.5
15.0
12.0
9.0
6.0
3.0
0.0
I
DD
SUPPLY CURRENT (mA)
–40
25°C
85°C
V
EE
SUPPLY VOLTAGE (V)
429071 G08
–60 –50 –40 –30 –20
9.0
8.5
8.0
7.0
7.5
6.5
6.0
I
EE
SUPPLY CURRENT (mA)
–40
25°C
85°C