Datasheet

5
LTC1642
1642fb
V
CC
(V)
02550
I
CC
(mA)
1642 G25
20
10
0
V
ON
= 5V
T
A
= 25°C
V
ON
= 0V
TYPICAL PERFOR A CE CHARACTERISTICS
UW
I
CC
vs V
CC
ON Pin Threshold Voltage vs
Temperature
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125
ON PIN THRESHOLD VOLTAGE (V)
1642 G22
1.40
1.36
1.32
1.28
1.24
1.20
V
CC
= 12V
ON RISING
ON FALLING
V
CC
(V)
3
6 9 12 15
V
REF
(V)
1642 G24
1.232
1.228
1.224
1.220
1.216
1.212
1.208
T
A
= 25°C
V
REF
vs V
CC
V
CC
(V)
3
6 9 12 15
PULL-UP CURRENT (µA)
1642 G14
160
140
120
100
80
60
40
20
0
T
A
= –55°C
T
A
= 125°C
T
A
= 25°C
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125
VOLTAGE (mV)
1642 G16
600
500
400
300
200
100
0
V
CC
= 12V
V
CC
= 5V
V
CC
= 15V
V
CC
= 3V
I
OL
= 1.54mA
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125
VOLTAGE (V)
1642 G17
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
V
CC
= 12V
V
CC
= 5V
V
CC
= 15V
V
CC
= 3V
I
OL
= 5mA
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125
CURRENT LIMIT THRESHOLD VOLTAGE (mV)
1642 G20
27.5
27.0
26.5
26.0
25.5
25.0
24.5
V
CC
= 3V
FB = 0V
V
CC
= 15V
V
CC
= 12V
V
CC
= 5V
FAULT and RESET Pull-Up Current
(I
OH
) vs V
CC
FAULT and RESET V
OL
vs
Temperature
FAULT and RESET V
OL
vs
Temperature
Current Limit Threshold Voltage
(Full Foldback) vs Temperature
Current Limit Threshold Voltage
(Nominal) vs Temperature
TEMPERATURE (°C)
–50 –25 0 25 50 75 100 125
CURRENT LIMIT THRESHOLD VOLTAGE (mV)
1642 G21
57.0
56.5
56.0
55.5
55.0
54.5
54.0
53.5
V
CC
= 3V
FB = 1V
V
CC
= 15V
V
CC
= 5V
V
CC
= 12V
Reference O/P Impedance
I
REF
(mA)
0 2.5
5 7.5 10 12.5 15 17.5 20
∆V
REF
(mV)
1642 G37
0
–2
–4
–6
–8
–10
–12
–14
–16
–18
–20
–22
–42
V
CC
= 12V,
15V
T
A
= 25°C
V
CC
= 5V
V
CC
= 3.3V