Datasheet

LTC4278
6
4278fc
Signature Resistance
vs Input Voltage
PWRGD, T2P Output Low Voltage
vs Current
Active High PWRGD
Output Low Voltage vs Current Inrush Current vs Input Voltage
CURRENT (mA)
0
V
PWRGD
– V
PORTN
(V)
V
T2P
– V
PORTN
(V)
0.4
0.6
8
4278 G07
0.2
0
2
4
6
10
0.8
T
A
= 25°C
!
CURRENT (mA)
0
0
PWRGD (V)
0.4
1.0
0.5
1
4278 G08
0.2
0.8
0.6
1.5
2
T
A
= 25°C
V
PORTP
– V
NEG
= 4V
V
PORTP
VOLTAGE (V)
40
85
CURRENT (mA)
115
45 50
4278 G09
55 60
90
100
105
110
95
90
100
105
110
95
Class Operation vs Time On-Resistance vs Temperature
V
PORTP
VOLTAGE (V)
1
22
V1:
V2:
SIGNATURE RESISTANCE (kΩ)
23
25
26
27
3
5
4278 G04
24
7
9
6 10
2 4
8
28
RESISTANCE =
DIODES: HD01
T
A
= 25°C
=
ΔV
ΔI
V2 – V1
I
2
– I
1
IEEE UPPER LIMIT
IEEE LOWER LIMIT
LTC4278 ONLY
!
LTC4278 + 2 DIODES
V
PORTP
VOLTAGE
10V/DIV
CLASS
CURRENT
10mA/DIV
TIME (10µs/DIV)
4278 G05
T
A
= 25°C
!
JUNCTION TEMPERATURE (°C)
–50
0.2
RESISTANCE (Ω)
0.4
0.6
0.8
1.0
–25
0 25 50
4278 G06
75 100
TYPICAL PERFORMANCE CHARACTERISTICS
Input Current vs Input Voltage
25k Detection Range Input Current vs Input Voltage Input Current vs Input Voltage
V
PORTP
VOLTAGE (V)
0
0
V
PORTP
CURRENT (mA)
0.1
0.2
0.3
0.4
0.5
2
4 6 8
4278 G01
10
T
A
= 25°C
V
PORTP
VOLTAGE (V)
(RISING)
0
0
V
PORTP
CURRENT (mA)
10
20
30
40
50
10
20 30 40
4278 G02
50 60
T
A
= 25°C
CLASS 4
CLASS 3
CLASS 2
CLASS 1
CLASS 0
!
V
PORTP
VOLTAGE (V)
12
9.5
V
PORTP
CURRENT (mA)
10.5
14
16
4278 G03
10.0
18
20 22
11.0
85°C
–40°C
CLASS 1 OPERATION
!